Éditeur(s) : University of West Indies, Trinidad &Tobago Université des Antilles. Service commun de la documentation
Extrait de : 52e congrès annuel de la Société caribéenne des plantes alimentaires / 52nd annual meeting of the Caribbean food crops society (CFCS), du 10 au 16 juillet 2016. INRA, CFCS
Description : Carbon dioxide (CO2) accounts for the largest proportion (74%) of total greenhouse gas (GHG) emissions globally, with agricultural activities contributing approximately 25% of this gas. Opportunities to reduce the emissions in the sector can therefore contribute significantly to mitigating global climate change. Ag-lime is used extensively to alleviate problems of soil acidity and the potential for this material to contribute to C sequestration in soils is gaining interest among researchers. A laboratory experiment using C-13 isotopic labelling techniques was therefore established to answer the following questions: 1) Is there a potential for sequestering C using ag-lime in Trinidad acid soils? 2) Does enhancing soil microbial respiration by applying labile organic amendments enhance the C sequestration potential of ag-lime? 3) Are lime-derived C (LDC) estimates from non-isotopic difference technique comparable to that from the C- 13 isotopic labelling technique? The results ascertained for the study showed significant (P<0.05) differences between the LDC estimates from the two techniques with the non-isotopic techniques yielding higher estimates. Over the 32- day experiment, between 16.4 to 85.4% of the ag-lime C was released as CO2 with values being lower for the Piarco soil. The LDC in the CO2 was also significantly (P<0.05) lower for the poultry litter treatments comparison to the other organic amendments for the Piarco soil but not the Nariva soil. This effect may not have been as a result of an enhancement of the carbon sequestration potential of the ag-lime due to an elevation in soil microbial respiration since the LDC in the glucose-amended soils did not differ significantly from the no-amendment control soils.
Siècle(s) traité(s) : 21
Droits : CC-BY-NC-ND - Attribution - Pas d'utilisation commerciale - Pas de modification
Permalien : http://www.manioc.org/fichiers/V16308
V16308

Éditeur(s) : HAL CCSD ACSM
Résumé : International audience
The aim of this study was to examine the effects of the cycle-run and run-cycle successions of the triathlon and duathlon, respectively, on respiratory muscle strength and endurance. Methods: Respiratory muscle strength was assessed by measuring maximal inspiratory (P1max) and expiratory {PEmax) pressures. Respiratory muscle endurance was assessed by measuring the time limit (Tlim). Twelve triathleles participated in a three-trial protocol. The first trial consisted of an incremental cycle test to assess the maximal oxygen uptake (VO2max) of triathletes. Trial 2 consisted of 20 min of cycling followed by 20 min of running (C-R), and trial 3 consisted of 20 min of running followed by 20 min of cycling (R-C). Trials 2 and 3 were performed at the same metabolic intensity (% VO2max). P1max and P1max were measured before and 10 min after C-R and R-C, and I min after the post-C-R and post-R-C Tlim measurements (P1max l'). Tlim was measured I d before and 30 min after C-R and R-C. Results: The results showed a significant decrease in P1max after C-R (126.7 ± 4.3 cmH2O, P < 0.05) and R-C (123.7 ± 4.9 cmH2O, P < 0.05) compared with the baseline values (130 ± 3.8 and 129.6 ± 4.3 cmH2O, respectively). P1max 1' showed a significantly greater decrease after R-C versus C-R(111.2 ± 5.5 cmH2O vs 121.2 ± 3.9 cmH2O,respectively, P < 0.001). Tlim after C-R (3.3 ± 0.3 min) decreased significantly compared with baseline values (4.19 ± 0.3min and 4.02 ± 0.3 min, respectively). However, the Tlim decrease after R-C was significantly greater than after C-R (P < 0.001). Conclusion: We concluded that respiratory muscle strength and endurance were less decreased after the cycle-run succession and that cycling induced a greater decrease in respiratory muscle endurance than running.
Medicine & Science in Sports & exercise

hal-00720796
https://hal.univ-antilles.fr/hal-00720796

Éditeur(s) : HAL CCSD Thieme Publishing
Résumé : International audience
The aim of the present study was to compare the effects of prior cycling and a successive run on respiratory muscle performance during a cycle-run succession as performed in the triathlon. We hypothesized that despite the moderate intensity of exercise and the absence of exhaustion, the crouched cycling position would induce a decrease in respiratory muscle performance that would be reversed by the successive vertical run position. Ten male triathletes (22.6 +/- 1.1 yr) performed a four-trial protocol: (1) an incremental cycle test to assess maximal oxygen uptake (VO2max), (2) 20 min of cycling (C), (3) 20 min of running (R), and (4) 20 min of cycling followed by 20 min of running (C-R). Trials 2, 3 and 4 were performed at the same metabolic intensity, i. e., 75 % of VO2max. Respiratory muscle force was assessed by measuring maximal expiratory (P(Emax)) and inspiratory (P(Imax)) pressures from the functional residual capacity (FRC) before and 10 min after C, R, and C-R. Respiratory muscle endurance was assessed one day before and 30 min after C, R, and C-R, by measuring the time limit (T(lim)), which corresponds to the length of time a respiratory load can be sustained before the process of fatigue develops sufficiently to cause task failure. The results showed a similar significant decrease in P(Imax) (132.4 +/- 4.9 versus 125.7 +/- 5.6 cm H2O, p < 0.05) and T(lim) (5.22 +/- 0.28 versus 3.68 +/- 0.32 min, p < 0.05) post-C and post-C-R (133.7 +/- 4.0 versus 126.9 +/- 5.2 cm H2O, and 5.29 +/- 0.18 versus 3.49 +/- 0.41 min, respectively, p < 0.05) compared with the pre-trial values. In contrast, P(Imax) and T(lim) were not significantly decreased post-R (131.8 +/- 6.1 cm H2O versus 129.6 +/- 6.4 cm H2O, and 4.90 +/- 0.69 versus 4.40 +/- 0.56 min, respectively, p > 0.05). We concluded that moderate intensity exercise not performed to exhaustion induced a decrease in respiratory muscle performance. Moreover, the respiratory muscle fatigue induced by prior cycling was maintained, and neither reversed nor worsened, by the successive run.
ISSN: 0172-4622

hal-00720715
https://hal.univ-antilles.fr/hal-00720715

Éditeur(s) : HAL CCSD Wiley
Résumé : The allocation and cycling of carbon (C) within forests is an important component of the biospheric C cycle, but is particularly understudied within tropical forests. We synthesise reported and unpublished results from three lowland rainforest sites in Amazonia (in the regions of Manaus, Tapajos and Caxiuana), all major sites of the Large-Scale Biosphere-Atmosphere Programme (LBA). We attempt a comprehensive synthesis of the C stocks, nutrient status and, particularly, the allocation and internal C dynamics of all three sites. The calculated net primary productivities (NPP) are 10.1 +/- 1.4 Mg C ha(-1) yr(-1) (Manaus), 14.4 +/- 1.3 Mg C ha(-1) yr(-1) (Tapajos) and 10.0 +/- 1.2 Mg C ha(-1) yr(-1) (Caxiuana). All errors bars report standard errors. Soil and leaf nutrient analyses indicate that Tapajos has significantly more plant-available phosphorus and calcium. Autotrophic respiration at all three sites (14.9-21.4 Mg C ha yr(-1)) is more challenging to measure, with the largest component and greatest source of uncertainty being leaf dark respiration. Comparison of measured soil respiration with that predicted from C cycling measurements provides an independent constraint. It shows general good agreement at all three sites, with perhaps some evidence for measured soil respiration being less than expected. Twenty to thirty percent of fixed C is allocated belowground. Comparison of gross primary productivity (GPP), derived from ecosystem flux measurements with that derived from component studies (NPP plus autotrophic respiration) provides an additional crosscheck. The two approaches are in good agreement, giving increased confidence in both approaches to estimating GPP. The ecosystem carbon-use efficiency (CUEs), the ratio of NPP to GPP, is similar at Manaus (0.34 +/- 0.10) and Caxiuana (0.32 +/- 0.07), but may be higher at Tapajos (0.49 +/- 0.16), although the difference is not significant. Old growth or infertile tropical forests may have low CUE compared with recently disturbed and/or fertile forests.
ISSN: 1354-1013

hal-01032150
https://hal.archives-ouvertes.fr/hal-01032150
DOI : 10.1111/j.1365-2486.2008.01780.x

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
Purpose The objective of this article was to estimate the social cost of respiratory cancer cases attributable to occupational risk factors in France in 2010. Methods According to the attributable fraction method and based on available epidemiological data from the lit- erature, we estimated the number of respiratory cancer cases due to each identified risk factor. We used the cost- of-illness method with a prevalence-based approach. We took into account the direct and indirect costs. We estimated the cost of production losses due to morbidity (absenteeism and presenteeism) and mortality costs (years of production losses) in the market and nonmarket spheres. Results The social cost of lung, larynx, sinonasal and mesothelioma cancer caused by exposure to asbestos, chromium, diesel engine exhaust, paint, crystalline silica, wood and leather dust in France in 2010 were estimated at between 917 and 2,181 million euros. Between 795 and 2,011 million euros (87-92 %) of total costs were due to lung cancer alone. Asbestos was by far the risk factor representing the greatest cost to French society in 2010 at between 531 and 1,538 million euros (58-71 %), ahead of diesel engine exhaust, representing an estimated social cost of between 233 and 336 million euros, and crystalline silica (119-229 million euros). Indirect costs represented about 66 % of total costs. Conclusion Our assessment shows the magnitude of the economic impact of occupational respiratory cancers. It allows comparisons between countries and provides valu- able information for policy-makers responsible for defining public health priorities.
ISSN: 1618-7598

halshs-00922838
https://halshs.archives-ouvertes.fr/halshs-00922838
DOI : 10.1007/s10198-013-0528-6
PUBMED : 23974964

Éditeur(s) : HAL CCSD Society for Range Management
Résumé : Grasslands and agroecosystems occupy one-third of the terrestrial area, but their contribution to the global carbon cycle remains uncertain. We used a set of 316 site-years of CO(2) exchange measurements to quantify gross primary productivity, respiration, and light-response parameters of grasslands, shrublands/savanna, wetlands, and cropland ecosystems worldwide. We analyzed data from 72 global flux-tower sites partitioned into gross photosynthesis and ecosystem respiration with the use of the light-response method (Gilmanov, T. G., D. A. Johnson, and N. Z. Saliendra. 2003. Growing season CO(2) fluxes in a sagebrushsteppe ecosystem in Idaho: Bowen ratio/energy balance measurements and modeling. Basic and Applied Ecology 4:167-183) from the RANGEFLUX and WORLDGRASSAGRIFLUX data sets supplemented by 46 sites from the FLUXNET La Thuile data set partitioned with the use of the temperature-response method (Reichstein, M., E. Falge, D. Baldocchi, D. Papale, R. Valentini, M. Aubinet, P. Berbigier, C. Bernhofer, N. Buchmann, M. Falk, T. Gilmanov, A. Granier, T. Grunwald, K. Havrankova, D. Janous, A. Knohl, T. Laurela, A. Lohila, D. Loustau, G. Matteucci, T. Meyers, F. Miglietta, J.M. Ourcival, D. Perrin, J. Pumpanen, S. Rambal, E. Rotenberg, M. Sanz, J. Tenhunen, G. Seufert, F. Vaccari, T. Vesala, and D. Yakir. 2005. On the separation of net ecosystem exchange into assimilation and ecosystem respiration: review and improved algorithm. Global Change Biology 11: 1.424-1439). Maximum values of the quantum yield (alpha = 75 mmol.mol(-1)), photosynthetic capacity (A(max) = 3.4 mg CO(2) . m(-2).s-1), gross photosynthesis (P(g,max) = 1.16 g CO(2) . m(-2).d(-1)), and ecological light-use efficiency (epsilon(ecol) = 59 mmol . mol(-1)) of managed grasslands and high-production croplands exceeded those of most forest ecosystems, indicating the potential of nonforest ecosystems for uptake of atmospheric CO(2). Maximum values of gross primary production (8 600 g CO(2) . m(-2).yr(-1)), total ecosystem respiration (7 900 g CO(2) . m(-2).yr(-1)), and net CO(2) exchange (2 400 g CO(2) . m(-2).yr(-1)) were observed for intensively managed grasslands and high-yield crops, and are comparable to or higher than those for forest ecosystems, excluding some tropical forests. On average, 80% of the nonforest sites were apparent sinks for atmospheric CO(2), with mean net uptake of 700 g CO(2) . m(-2).yr(-1) for intensive grasslands and 933 g CO(2) . m(-2).d(-1) for croplands. However, part of these apparent sinks is accumulated in crops and forage, which are carbon pools that are harvested, transported, and decomposed off site. Therefore, although agricultural fields may be predominantly sinks for atmospheric CO(2), this does not imply that they are necessarily increasing their carbon stock.
ISSN: 1550-7424

hal-01190754
https://hal.archives-ouvertes.fr/hal-01190754
DOI : 10.2111/rem-d-09-00072.1
PRODINRA : 214043

Éditeur(s) : HAL CCSD Cambridge University Press (CUP)
Résumé : The objective of this study was to analyse the factors explaining spatial variation in soil respiration over topographic transects in a tropical rain forest of French Guiana. The soil of 30 plots along six transects was characterized. The appearance of the 'dry to the touch' character at a depth of less than 1.2 m was used to discriminate soils exhibiting vertical drainage from soils exhibiting superficial lateral drainage and along with colour and texture, to define five classes from well-drained to strongly hydromorphic soils. Spatial variation in soil respiration was closely related to topographic position and soil type. Increasing soil water content and bulk density and decreasing root biomass and soil carbon content explained most of the decrease in soil respiration from the plateaux (vertically drained hypoferralic acrisol) to the bottomlands (haplic gleysol). These results will help to stratify further field experiments and to identify the underlying determinants of spatial variation in soil respiration to develop mechanistic models of soil respiration.
ISSN: 0266-4674

hal-01032046
https://hal.archives-ouvertes.fr/hal-01032046
DOI : 10.1017/S0266467406003415

Éditeur(s) : Actes de colloques. Ifremer Brest [ACTES COLLOQ. IFREMER.]. 1986
Résumé : Bacterial density of the coelenteric fluid (CF) of some anthozoan species was determined in situ and under laboratory conditions. In all species examined bacterial density of the CF was higher in the gastral cavity than in ambient ranging from 10 super(5) up to 5 x 10 super(6) cells. ml super(-1). Incubation experiments with the CF indicate that a bacterial population within the coelenteron is efficiently controlled by the CF, favoring bacterial growth if bacterial densities are low in the CF and showing clearance activity at high bacterial densities. Feeding of pre-starved anthozoans caused a rapid response of coelenteric rod-shaped bacteria. Evidence is presented that coelenteric bacteria are digested periodically although they contribute 1% to the respiratory carbon losses of the antozoans tested. Therefore, it is more likely that the coelenteric bacterial population provide other substances which cannot be synthesized by the host.
La densité des bactéries du fluide gastrique de différents anthozoaires a été déterminée in situ et au laboratoire. Pour toutes les espèces étudiées, la densité des bactéries dans le fluide gastrique était plus élevée que dans l'eau ambiante et comprise entre 105et 106 cellules m"1. Des expériences d'incubation du fluide gastrique montrent que la population bactérienne est contrôlée efficacement par ce fluide gastrique, favorisant la croissance de bactéries lorsque la densité est faible mais révélant des activités de digestion lorsque la densité est élevée. En nourrissant des anthozoaires mis àjeun plusieurs jours, on provoque une réaction rapide des bactéries déforme bacillaire. Certaines observations montrent que les bactéries gastriques se développent et sont digérées par cycle dans le coelenteron. Néanmoins, la contribution en carbone de ces dernières, comparée aux pertes d'énergie par Sa respiration, représenterait moins de i ','-£. li est probable que cette population bactérienne fournisse des substances qui ne peuvent être synthétisées par i'hôte.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/1984/acte-989.pdf
http://archimer.ifremer.fr/doc/00000/989/

Éditeur(s) : HAL CCSD Thieme Publishing
Résumé : International audience
The aim of the present study was to compare the effects of prior cycling and a successive run on respiratory muscle performance during a cycle-run succession as performed in the triathlon. We hypothesized that despite the moderate intensity of exercise and the absence of exhaustion, the crouched cycling position would induce a decrease in respiratory muscle performance that would be reversed by the successive vertical run position. Ten male triathletes (22.6 +/- 1.1 yr) performed a four-trial protocol: (1) an incremental cycle test to assess maximal oxygen uptake (VO2max), (2) 20 min of cycling (C), (3) 20 min of running (R), and (4) 20 min of cycling followed by 20 min of running (C-R). Trials 2, 3 and 4 were performed at the same metabolic intensity, i. e., 75 % of VO2max. Respiratory muscle force was assessed by measuring maximal expiratory (P(Emax)) and inspiratory (P(Imax)) pressures from the functional residual capacity (FRC) before and 10 min after C, R, and C-R. Respiratory muscle endurance was assessed one day before and 30 min after C, R, and C-R, by measuring the time limit (T(lim)), which corresponds to the length of time a respiratory load can be sustained before the process of fatigue develops sufficiently to cause task failure. The results showed a similar significant decrease in P(Imax) (132.4 +/- 4.9 versus 125.7 +/- 5.6 cm H2O, p < 0.05) and T(lim) (5.22 +/- 0.28 versus 3.68 +/- 0.32 min, p < 0.05) post-C and post-C-R (133.7 +/- 4.0 versus 126.9 +/- 5.2 cm H2O, and 5.29 +/- 0.18 versus 3.49 +/- 0.41 min, respectively, p < 0.05) compared with the pre-trial values. In contrast, P(Imax) and T(lim) were not significantly decreased post-R (131.8 +/- 6.1 cm H2O versus 129.6 +/- 6.4 cm H2O, and 4.90 +/- 0.69 versus 4.40 +/- 0.56 min, respectively, p > 0.05). We concluded that moderate intensity exercise not performed to exhaustion induced a decrease in respiratory muscle performance. Moreover, the respiratory muscle fatigue induced by prior cycling was maintained, and neither reversed nor worsened, by the successive run.
ISSN: 0172-4622

hal-01622938
https://hal-umontpellier.archives-ouvertes.fr/hal-01622938
DOI : 10.1055/s-2003-37201
PUBMED : 12582954

Éditeur(s) : HAL CCSD
Résumé : International audience
BACKGROUND: The effects of pressure-controlled (PC) ventilation on the ventilatory and haemodynamic parameters during laparoscopy procedures had not been carefully assessed. This prospective cross-over study was undertaken to compare how volume-controlled (VC) and PC modes could affect pulmonary mechanics, gas exchange, and cardiac function in patients undergoing laparoscopy. METHODS: Twenty-one patients undergoing laparoscopic urological procedures had their lungs ventilated at the beginning with VC ventilation. PC ventilation was instituted at the end of the VC sequence. Ventilator settings were adjusted to keep tidal volume, respiratory rate, and Fi(o(2)) constant in every mode. A complete set of ventilatory, haemodynamic, and gas exchange parameters was obtained under VC after 40 min of pneumoperitoneum and 20 min after switching for PC. Transoesophageal echocardiography was performed in order to evaluate systolic and diastolic function of the heart. RESULTS: When VC was switched to PC, peak airway pressure decreased [mean (sd) 32 (6) vs 27 (6) cm H(2)O; P < 0.0001], peak inspiratory flow increased [17 (3) vs 48 (8) litre min(-1); P < 0.0001), and dynamic compliance improved [+15 (8)%]. No difference was noted for static airway pressure, static compliance, and arterial oxygenation. No significant change could be demonstrated in the systolic [left ventricular end-systolic wall stress 66 (16) vs 63 (14) x 10(3) dyn cm(-2) m(-2)] or diastolic function [early diastolic velocity 10.3 (2.5) vs 10.5 (2.7) cm s(-1)]. CONCLUSIONS: In this study, no short-term beneficial effect of PC ventilation could be demonstrated over conventional VC ventilation in patients with pneumoperitoneum.
BJA

hal-00689758
https://hal.archives-ouvertes.fr/hal-00689758
DOI : 10.1093/bja/aem166
PUBMED : 17626027

Éditeur(s) : Université de Guyane
Extrait de : "Bals masqués de Guyane et d'ailleurs. Identités et imaginaires carnavalesques en question" : colloque international, les 26 et 27 janvier 2017. Université de Guyane
Description : Les juristes se sentent un peu un intrus dans le monde du carnaval, il y a priori un décalage entre la rigueur bien connu du droit et la liberté carnavalesque. Le carnaval peut prendre ces distances à travers le droit, parfois ridiculiser certaines institutions juridiques(le mariage burlesque). Le droit peut s'effacer pour laisser place à la liberté du carnaval. Le carnaval serait un moment de respiration du droit ou le droit cesserait de faire peser son cadre normatif. Le carnaval a besoin du droit afin de faire respecter certaines exigences élémentaires de la sécurité des biens et des personnes.
Siècle(s) traité(s) : 21
Droits : CC-BY-NC-ND - Attribution - Pas d'utilisation commerciale - Pas de modification
Permalien : http://www.manioc.org/fichiers/V17098
V17098

Éditeur(s) : HAL CCSD
Résumé : Diffusion du document : INRA Documentation de Centre, Domaine de Duclos, 97170 Petitt-Bourg (Guadeloupe, France) Diplôme : DEA
il s'agit d'un type de produit dont les métadonnées ne correspondent pas aux métadonnées attendues dans les autres types de produit : DISSERTATION
Because soil respiration representes 80% of ecosystem respiration, it is a major flux between biosphere and atmosphere. We examined the effects of root and litter exclusion on soil CO! efflux (Rsu1) using trenching and litter exclusion in a tropical plantation constituted of trees seedlings installed in 16 mono-specific stands 20 years ago near Kourou, French Guyana. Soil CO2 efflux was measured using an infra red gas analyser (PP System,EGM4 ) at 16 randomly distributed plot in each treatment: control, root exclusion, litter exclusion and both root and litter exclusion. in the plantation. We measured R'1l1during four periods, and we have collected soil samples, litter biomass and measured moisture at 5 cm depth in the soil. Soil CO, efflux varied significantly among species from 2,8±O,7f1mo l. m''. s' (mean ± standard deviation) to 7.4± 1.7fLmol. n'-' . s ' for Qualea rosea and Vochys ia tomentosa, respectively. 1'0 significant correlation was found between RSIlI variability and soil moisture, which is mostly related to soil texture in the experimental site. Soil CO2 efflux was significantly reduced in litter exclusion treatment and root exclusion plots (6 months litter and/or root exclusion) during ail measurements period and for ail species, compared to control plots. The reduction of soil CO, efflux was higher in plot without root than in plot without litter of control plot (42% and 25%, respectively). There was an import ant specific diversity in these reductions . We estimated the contribution of roof respiration (Rr) to total Rso1 by calculating the difference between Rso1 control and Rsn l root exclusion plot corrected for the decomposition of root that were killed following t re n e h in ~. Thus the heterotrophic component of soil carbon efflux accounts for 46% of total carbon efflux (1,9f1 mol. rn" . s•') while root respiration accounts for 54% of soil carbon release (2,3 ~t mo l. m-2 S-I) . Because there was a negative and significant correlation between microbial respiration (Rrn) and C/N of mature leaves it seemed to be possible to predict Rm if we known the mature leaves quality. In addition a good estimate theorical R ~, values from R~, measured in different treatments.
La respiration du sol en représentant une part de 80% de la respiration de l'écosystème apparaît être un flux majeur entre la biosphère et l'atmosphère. Nous avons étudié les effets de l'exclusion racinaire et de la litière sur le flux de CO, du sol (R ~ , ) en utilisant la méthode de " Trench-plots" et de suppression de litière dans une plantation d'arbres tropicaux. Ces arbres, âgés de 20 ans ont été plantés sur un sol uniforme, près de Kourou en Guyane française, en 16 placeaux mono-spécifiques. Pour mesurer les flux de CO2 provenant du sol, nous avons utilisé un analyseur différentiel de gaz infrarouge portable muni d'une chambre. Les mesures ont été faites sur 4 traitements différents tels que : le contrôle, l'exclusion racinaire, l'exclusion de litière et l'exclusion de litière et de racine et ce, répétés sur chacune des 16 placettes mono-spécifiques. Cette étude comporte 4 campagnes de mesures. Nous avons également effectué des prélèvements de sol de litière et nous avons fait des mesures d’humidité de sol à une profondeur de 5 cm. Les flux de C01 du sol varient fortement entre espèces de 2.8±O.7 ~t m o 1. m-2. sol à 7 A± 1. 7 ~t m o l. m•1 sol pour Qua/ev rosea ct Vochysto tomentasa, respectivement. Il n'existe pas de corrélation significative entre les variations de Rw l ct celles de l'humidité du sol (indication sur la texture du sol de la plantation ). Nous avons observé que Rso1 était significativement plus faible dans les placeaux sans racines et/ou sans litière (6 mois après la mise en place de l'expérimentation) pour toutes les campagnes de mesures et pour toutes les espèces que dans les placeaux contrôlés. Cette réduction du flux de CO2 du sol est plus forte dans les "trench-plots " que dans les traitement s d'exclusion de litière avec 42 et 25% respectivement. Un effet "traitement " et un effet "espèce" important expliquent 3 1"/.. ct 13% de la variabilité totale de R~. Nous avons cherché à connaître la contribution des racines dans les valeurs de R""I. en comparant le flux de CO2 provenant du sol sur des "trench -plot s'' au flux de COl provenant du sol dans les placeaux contrôlés . Cette estimation a été corrigée pour prendre en compte la décomposition des racines tuées par les tranchées. Ainsi, la composante appartenant aux micro -organismes représente 46% du flux total de carbone provenant du sol (1.9Jlmo l. m-2 S•I ) alors que la respiration des racines représente 54% du dégagement de carbone (2 ,3~lmol. m ol . 5-La respiration des micro-organismes pourrait être estimée en mesurant le C/N des feuilles matures puisqu'il existe une corrélation significative et négative entre les deux. Enfin les résultats obtenus sur les différents traitements permettent d'obtenir une bonne estimation de la respiration du sol avec un RSIlI théorique corrélé à 66% avec les valeurs réelles mesurées.
https://hal.archives-ouvertes.fr/hal-01189239

hal-01189239
https://hal.archives-ouvertes.fr/hal-01189239
PRODINRA : 18212

Éditeur(s) : HAL CCSD
Résumé : International audience
This study investigated the possibility of there being differences in respiratory muscle strength and endurance in elite and competition triathletes who have similar maximal oxygen uptakes (V_O2max) and ventilatory thresholds (Thvent). Five internationally-ranked elite, [mean (SD) age 23.8 (1.4) years] and six nationallyand regionally-ranked competition [age 21.1 (1.1) years] male triathletes performed two successive trials: first an incremental cycle test to assess V_O2max and Thvent and second 20 min of cycling followed by 20 min of running (C-R) at intensities higher than 85% V_O2max. Cardioventilatory data were collected every minute during the two trials, using an automated breath-by-breath system. Maximal expiratory and inspiratory (PImax) strength were assessed before and 10 min after C-R from the functional residual capacity. Respiratory muscle endurance was assessed 1 day before and 30 min after C-R by measuring the time limit (tlim). The results showed firstly that during C-R, the competition triathletes had significantly (P<0.05) higher minute ventilation [mean (SEM) 107.4 (3.1) compared to 99.8 (3.7) lÆmin-1], breathing frequency [44.4 (2.0) compared to 40.2 (3.4) Æmin-1] and heart rate [166 (3) compared to 159 (4) beatsÆmin-1] and secondly that after C-R, they had significantly lower PImax [127.1 (4.2) compared to 130.7 (3.0) cmH2O] and tlim [2:35 (0:29) compared to 4:12 (0:20) min] than the elite triathletes. We conclude that, despite similar V_O2max and Thvent, the competition triathletes showed less extensive adaptive mechanisms, including those in the respiratory muscles, than did the elite triathletes. This led to higher ventilation, which appeared to be the cause of the faster development of fatigue in the inspiratory muscles in this group.
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY

hal-00720562
https://hal.univ-antilles.fr/hal-00720562
https://hal.univ-antilles.fr/hal-00720562/document
https://hal.univ-antilles.fr/hal-00720562/file/BoussanaEJAP02_2_.pdf

Éditeur(s) : Université des Antilles. Service commun de la documentation University of West Indies, Barbados
Extrait de : 52e congrès annuel de la Société caribéenne des plantes alimentaires / 52nd annual meeting of the Caribbean food crops society (CFCS), du 10 au 16 juillet 2016. INRA, CFCS
Description : Mulch application of Sargassum seaweed (Sargassum spp.) to soil can help to reduce beach contamination in the Caribbean Region while providing beneficial horticultural effects. This study investigated the effects of fresh Sargassum mulch on soil properties and plant growth in a test crop of tomato (Solanum lycopersicum L. â? ? HA 3019â? TM). Fresh Sargassum material (washed and unwashed) was applied as mulches (0, 5 and 8cm thick) to small field plots one week after transplanting of 3-week-old seedlings. The mulch material was raked away from the plots after three weeks exposure. Observations on soil moisture, electrical conductivity, pH and biological activity, and plant growth were made at 1 to 2-week intervals over a 6-week period with additional soil measurements after 10 weeks. Soil biological activity (respiration) was increased by the Sargassum mulch with values being similar for the 5cm and 8cm mulch layers. Soil moisture content, pH and electrical conductivity (EC) were increased as the mulch layer increased and EC values were only marginally reduced by Sargassum washing. An increase in plant growth compared to the control treatment was noted only in the washed Sargassum treatments. Potential benefits of Sargassum seaweed mulches on soil properties and plant growth can be nullified due to soil salinization effects.
Siècle(s) traité(s) : 21
Droits : CC-BY-NC-ND - Attribution - Pas d'utilisation commerciale - Pas de modification
Permalien : http://www.manioc.org/fichiers/V16269
V16269

Résumé : Actions menées de 1994 à 1998 au sein du conservatoire de souches : 1. Résultats des importations, acclimatation et hybridation. a) Rappel des conditions d'introduction de nouvelles souches. L'importation de toute espèce est conditionnée par les résultats d'une enquête préliminaire dont l'objet est de rechercher les exigences écologiques de l'espèce et la situation épidémiologique dans son milieu d'origine. Le travail du LGP et de ses partenaires a été partagé en différentes actions: 1. Recherche de contacts dans divers pays étrangers, en vue de l'importation d'huîtres présentant des caractéristiques intéressantes. 2. Importation : L'importation se fait selon les normes du CIEM (Conseil International pour l'Exploration de la Mer) : contrôles pathologiques sur les lots d'animaux importés, confinement en salle de quarantaine des géniteurs avec stérilisation systématique des eaux de rejet, sacrifice des géniteurs après la production de la première génération. 3. Production d'une première descendance: La ponte est également réalisée en salle de quarantaine. Des contrôles pathologiques auront lieu tout au long de l'élevage. 4. Contrôle des performances : ils se font, dans un premier temps, uniquement au laboratoire avec stérilisation des eaux de rejet. Cette caractérisation intègre différentes approches : résistance aux parasites présents dans le milieu français, caractères quantitatifs (poids, taille, rendement, vitesse de croissance), polymorphisme enzymatique ou ADN, tests physiologiques (mesure de la respiration, du rendement d'assimilation ... ). 5. Hybridation: Des hybridations entre espèces ont été tentées, avec contrôle par marqueurs génétiques. 6. Conservatoire de souches : Les générations F1 des différentes espèces ont systématiquement été conservées. Une salle a été spécialement équipée au LGP dans cet objectif.

Droits : 1998 Ifremer
http://archimer.ifremer.fr/doc/00044/15520/12907.pdf
http://archimer.ifremer.fr/doc/00044/15520/12922.pdf
http://archimer.ifremer.fr/doc/00044/15520/

Éditeur(s) : HAL CCSD
Résumé : International audience
The aim of the present study was to determine the effects of 40 km of cycling on the biomechanical and cardiorespiratory responses measured during the running segment of a classic triathlon, with particular emphasis on the time course of these responses. Seven male triathletes underwent four successive laboratory trials: (1) 40 km of cycling followed by a 10-km triathlon run (TR), (2) a 10-km control run (CR) at the same speed as TR, (3) an incremental treadmill test, and (4) an incremental cycle test. The following ventilatory data were collected every minute using an automated breath-by-breath system: pulmonary ventilation VE, l x min[-1]), oxygen uptake (VO2, ml x min(-1) x kg[-1]), carbon dioxide output (ml x min[-1]), respiratory equivalents for oxygen (VE/VO2) and carbon dioxide (VE/VCO2), respiratory exchange ratio (R) respiratory frequency (f, breaths x min[-1]), and tidal volume (ml). Heart rate (HR, beats x min[-1]) was monitored using a telemetric system. Biomechanical variables included stride length (SL) and stride frequency (SF) recorded on a video tape. The results showed that the following variables were significantly higher (analysis of variance, P < 0.05) for TR than for CR: VO2 [51.7 (3.4) vs 48.3 (3.9) ml x kg(-1) x min(-1), respectively], VE [100.4 (1.4) l x min(-1) vs 84.4 (7.0) l x min(-1)], VE/VO2 [24.2 (2.6) vs 21.5 (2.7)] VE/VCO2 [25.2 (2.6) vs 22.4 (2.6)], f[55.8 (11.6) vs 49.0 (12.4) breaths x min(-1)] and HR [175 (7) vs 168 (9) beats x min(-1)]. Moreover, the time needed to reach steady-state was shorter for HR and VO2 (1 min and 2 min, respectively) and longer for VE (7 min). In contrast, the biomechanical parameters, i.e. SL and SF, remained unchanged throughout TR versus CR. We conclude that the first minutes of the run segment after cycling in an experimental triathlon were specific in terms of VO2 and cardiorespiratory variables, and nonspecific in terms of biomechanical variables.
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY

hal-00720703
https://hal.univ-antilles.fr/hal-00720703
https://hal.univ-antilles.fr/hal-00720703/document
https://hal.univ-antilles.fr/hal-00720703/file/EJAP.pdf

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
Bronchoalveolar lavage (BAL) is a major diagnostic tool in lung diseases, including viral respiratory infections. We aimed to better define the situations where viral tests should be performed on BAL fluid (BALF). We retrospectively studied all cases where viral tests [immunofluorescence, immunocytochemistry, viral culture, and/or polymerase chain reaction (PCR)] were performed on BALF during a period of 1 year (2008) in our institution. We compared the characteristics of patients with virus-positive versus virus-negative BALF. Of the 636 BALF samples sent to the microbiology laboratory, 232 underwent viral tests. Of these, 70 (30 %) were positive and identified 85 viruses: herpes simplex virus (HSV)-1 (n = 27), cytomegalovirus (CMV, n = 23), Epstein-Barr virus (EBV, n = 18), human herpesvirus (HHV)-6 (n = 12), respiratory syncytial virus (RSV, n = 3), rhinovirus (n = 1), and adenovirus (n = 1). The variables associated with positive viral tests on univariate analysis were immunosuppression [human immunodeficiency virus (HIV), corticosteroids >10 mg/day for ≥3 weeks, or other immunosuppressive therapy], ground-glass attenuations on computed tomography (CT) scanning, late-onset ventilator-associated pneumonia (VAP), and durations of (i) hospital stay, (ii) intensive care unit (ICU) stay, and (iii) mechanical ventilation before BAL (p < 0.01 for each comparison). On multivariate analysis, only immunosuppression [odds ratio (OR) 6.4, 95 % confidence interval (CI) [2.8-14.3], p < 0.0001] and ground-glass attenuations (OR 3.7, 95 % CI [1.8-7.7], p = 0.0004) remained associated with virus-positive BAL. None of the viral tests performed on BALF for the initial assessment of diffuse infiltrative lung disease (n = 15) was positive. PCR improved the diagnostic yield of viral tests on BALF by 50 %. Testing for viruses on BALF should be mostly restricted to immunocompromised patients with acute respiratory diseases and/or patients with unexplained ground-glass attenuations on CT scanning.
ISSN: 0934-9723

hal-00873158
https://hal.archives-ouvertes.fr/hal-00873158
DOI : 10.1007/s10096-012-1791-7
PUBMED : 23238685

Éditeur(s) : Elsevier
Résumé : Herbivorous (20% vegetable protein, 40% carbohydrate) and carnivorous diets (40% marine animal protein, 20% carbohydrate) were experimentally tested to assess their effect on the energy balance and energetic substrates utilized by postlarvae (PL's /15 days) and juvenile shrimp (3-6 g) of Litopenaeus vannamei. Postlarval stage 60 (PL60, early juveniles) shrimps fed HeD and CaD diets, then late juveniles (3-6 g) acclimated to the same diets were tested for their respective energy partitioning potential. No significant differences (p>0.05) on growth were obtained in early juveniles (mean final wet weight of 0.19 g). However in late juvenile stages a significant difference (p<0.05) in growth rate was observed. In terms of energy partitioning, both early and late juveniles seem to spend more energy in respiratory metabolism than in the elimination of excretion products. A change in feed composition based on quality protein sources induced some modifications on shrimp's activity measured by heat increment. Shrimps fed with an herbivorous diet showed a higher heat increment. Interestingly, the early stages of L vannamei display a remarkable capacity to assimilate a plant protein-based and a high carbohydrate level diet. Such capacity with a stimulation of genes would lead to a good adaptation of juveniles receiving all-plant diets to sustain growth performances up to a marketable size. The implications of these findings for the shrimp farming feeding costs are briefly discussed. (C) 2009 Elsevier B.V. All rights reserved.
Aquaculture (0044-8486) (Elsevier), 2009-11 , Vol. 296 , N. 1-2 , P. 123-128

Droits : 2009 Elsevier B.V. All rights reserved.
http://archimer.ifremer.fr/doc/2009/publication-7402.pdf
DOI:10.1016/j.aquaculture.2009.08.007
http://archimer.ifremer.fr/doc/00000/7402/

Éditeur(s) : HAL CCSD Springer Verlag
Résumé :  
The high spatial variability of soil respiration in tropical rainforests is well evaluated, but influences of biotic factors are not clearly understood. This study underlines the influence of tree species characteristics on soil respiration across a 16-monospecific plot design in a tropical plantation of French Guiana. A large variability of soil CO2 fluxes was observed among plots (i.e. 2.8 to 6.8 μmol m−2 s −1 ) with the ranking being constant across seasons. There were no significant relationships between soil respiration and soil moisture or soil temperature, neither spatially, nor seasonally. The variability of soil respiration was mainly explained by quantitative factors such as leaf litterfall and basal area. Surprisingly, no significant relationship was observed between soil respiration and root biomass. However, the influence of substrate quality was revealed by a strong relationship between soil respiration and litterfall P (and litterfall N, to a lesser extent).
ISSN: 0032-079X

hal-01032069
https://hal.archives-ouvertes.fr/hal-01032069
DOI : 10.1007/s11104-008-9866-z

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
The purpose of this investigation was to characterize the management and prognosis of severe Pneumocystis jirovecii pneumonia (PJP) in human immunodeficiency virus (HIV)-negative patients. An observational cohort study of HIV-negative adults with PJP documented by bronchoalveolar lavage (BAL) through Gomori-Grocott staining or immunofluorescence, admitted to one intensive care unit (ICU) for acute respiratory failure, was undertaken. From 1990 to 2010, 70 patients (24 females, 46 males) were included, with a mean age of 58.6 ± 18.3 years. The mean Simplified Acute Physiology Score (SAPS)-II was 36.9 ± 20.4. Underlying conditions included hematologic malignancies (n = 21), vasculitis (n = 13), and solid tumors (n = 13). Most patients were receiving systemic corticosteroids (n = 63) and cytotoxic drugs (n = 51). Not a single patient received trimethoprim-sulfamethoxazole as PJP prophylaxis. Endotracheal intubation (ETI) was required in 42 patients (60.0 %), including 38 with acute respiratory distress syndrome (ARDS). In-ICU mortality was 52.9 % overall, reaching 80.9 % and 86.8 %, respectively, for patients who required ETI and for patients with ARDS. In the univariate analysis, in-ICU mortality was associated with SAPS-II (p = 0.0131), ARDS (p < 0.0001), shock (p < 0.0001), and herpes simplex virus (HSV) or cytomegalovirus (CMV) on BAL (p = 0.0031). In the multivariate analysis, only ARDS was associated with in-ICU mortality (odds ratio [OR] 23.4 [4.5-121.9], p < 0.0001). PJP in non-HIV patients remains a serious disease with high in-hospital mortality. Pulmonary co-infection with HSV or CMV may contribute to fatal outcome.
ISSN: 0934-9723

inserm-00872789
http://www.hal.inserm.fr/inserm-00872789
DOI : 10.1007/s10096-012-1730-7
PUBMED : 22930407