Rates of consumption of atmospheric CO2 through the weathering of loess during the next 100 yr of climate change

in Biogeosciences (2013), 10

Quantifying how C fluxes will change in the future is a complex task for models because of the coupling between climate, hydrology, and biogeochemical reactions. Here we investigate how pedogenesis of the ... [more ▼]

Quantifying how C fluxes will change in the future is a complex task for models because of the coupling between climate, hydrology, and biogeochemical reactions. Here we investigate how pedogenesis of the Peoria loess, which has been weathering for the last 13 kyr, will respond over the next 100 yr of climate change. Using a cascade of numerical models for climate (ARPEGE), vegetation (CARAIB) and weathering (WITCH), we explore the effect of an increase in CO2 of 315 ppmv (1950) to 700 ppmv (2100 projection). The increasing CO2 results in an increase in temperature along the entire transect. In contrast, drainage increases slightly for a focus pedon in the south but decreases strongly in the north. These two variables largely determine the behavior of weathering. In addition, although CO2 production rate increases in the soils in response to global warming, the rate of diffusion back to the atmosphere also increases, maintaining a roughly constant or even decreasing CO2 concentration in the soil gas phase. Our simulations predict that temperature increasing in the next 100 yr causes the weathering rates of the silicates to increase into the future. In contrast, the weathering rate of dolomite – which consumes most of the CO2 – decreases in both end members (south and north) of the transect due to its retrograde solubility. We thus infer slower rates of advance of the dolomite reaction front into the subsurface, and faster rates of advance of the silicate reaction front. However, additional simulations for 9 pedons located along the north–south transect show that the dolomite weathering advance rate will increase in the central part of the Mississippi Valley, owing to a maximum in the response of vertical drainage to the ongoing climate change. The carbonate reaction front can be likened to a terrestrial lysocline because it represents a depth interval over which carbonate dissolution rates increase drastically. However, in contrast to the lower pH and shallower lysocline expected in the oceans with increasing atmospheric CO2, we predict a deeper lysocline in future soils. Furthermore, in the central Mississippi Valley, soil lysocline deepening accelerates but in the south and north the deepening rate slows. This result illustrates the complex behavior of carbonate weathering facing short term global climate change. Predicting the global response of terrestrial weathering to increased atmospheric CO2 and temperature in the future will mostly depend upon our ability to make precise assessments of which areas of the globe increase or decrease in precipitation and soil drainage. [less ▲]

Morphometric analyses of the body and the branches of the normal third interosseous muscle (suspensory ligament) in Standardbreds

in Anatomia, Histologia, Embryologia (2013)

The third interosseous muscle (suspensory ligament, TIOM) is composed of connective tissue (CT) with a variable proportion of muscle (MT) and adipose tissue (AT). The aim of our study is to quantify the ... [more ▼]

The third interosseous muscle (suspensory ligament, TIOM) is composed of connective tissue (CT) with a variable proportion of muscle (MT) and adipose tissue (AT). The aim of our study is to quantify the CT, MT and AT within the body and the branches of right thoracic and pelvic limbs TIOM in sound horses to determine whether there are differences in CT, MT and AT between age, sex, limbs and levels. Right limbs from 11 sound horses were collected. Samples from 6 levels of the TIOM were embedded in paraffin or in Tissue-Tek®. Most of the paraffin sections were shredded. Using the cryosection, some artefacts appeared. Cryoprotection was carried out, which produced the best results. Hematoxylin–phloxine–saffron and Hematoxylin–eosin gave a good contrast of colours between the tissues observed allowing the use of an image analysis programme to calculate percentage of each tissue within the TIOM. The percentage of MT and AT decreased significantly (P < 0.0001), whereas the percentage of CT increased significantly (P < 0.0001) with age and when descending from the proximal to the distal level of the TIOM. The percentage of MT was significantly higher (P < 0.0001) in females than males, while the percentage of CT was significantly higher (P < 0.0001) in males than females. The percentage of AT was significantly higher (P = 0.0278) in pelvic limbs than in thoracic limbs. These results confirm the variation in tissue composition within the TIOM of sound horses. [less ▲]

AKM coffee-growing cooperative and socio-economic development of Rwandan farmers, Huye District

Conference (2013)

La mécanique du détail. Approches transversales

Book published by Editions de l'Ecole Normale Supérieure de Lyon (2013)

Parce qu’elle a trait aux relations nouées entre les parties et l’ensemble qui les comprend, la question du détail s’investit d’enjeux considérables pour toute tentative de réflexion interdisciplinaire ... [more ▼]

Parce qu’elle a trait aux relations nouées entre les parties et l’ensemble qui les comprend, la question du détail s’investit d’enjeux considérables pour toute tentative de réflexion interdisciplinaire. En effet, dans les disciplines qui s’attachent à rendre un objet visible ou lisible, les théoriciens rencontrent à l’endroit du détail des problèmes voisins, sinon analogues, que nous voudrions ici aborder de front, dans une perspective forcément « rapprochée » et plus que jamais attentive à des objets singuliers, que ceux-ci relèvent de la littérature, du cinéma, de la photographie, de la bande dessinée, de la peinture, de la philosophie, etc. À confronter nos méthodes et les présupposés sur lesquels elles reposent, il nous a semblé possible de cerner plus finement le mode de fonctionnement propre au détail. Certes, chacun fera part ici de ses étonnements particuliers ; de même, chacun sera amené à faire rapport des découvertes enthousiasmantes ou perturbantes qui, dans son domaine spécifique, auront innervé le travail de réflexion. Pourtant, il aurait été inutile de vouloir dresser une simple liste de détails, recueillis au sein d’une compilation bariolée et forcément non exhaustive. Adoptant une perspective plus large, le présent ouvrage vise à une compréhension approfondie de la mécanique du détail (extrait de l'Avant-propos, L. Belloï & M. Hagelstein). [less ▲]

Integrating Experimental and Computational Fluid Dynamics approaches using Proper Orthogonal Decomposition Techniques

in Progress in Aerospace Sciences (2013)

The concept of Proper Orthogonal Decomposition (POD) is used to integrate Experimental Fluid Dynamics (EFD) and Computational Fluid Dynamics (CFD) approaches. The key idea is to take advantage of the ... [more ▼]

The concept of Proper Orthogonal Decomposition (POD) is used to integrate Experimental Fluid Dynamics (EFD) and Computational Fluid Dynamics (CFD) approaches. The key idea is to take advantage of the optimality of the POD technique and its capability to extract the most energetic patterns of complex aerodynamic flow fields. First, the concept of Modal Assurance Criterion (MAC) is used to obtain a simple quantitative criterion to compare EFD measurements to CFD results. The comparison is based on the POD modes, extracted from each set of data. The analysis of the energy content of the modes allows to draw important conclusions about the role of the latter. The method is applied in the study of the flow field around a rectangular cylinder, which is either static or oscillating in a low-speed flow field. The second EFD/CFD integration technique deals with the reconstruction of a flow field from measured data, making use of CFD simulation results. The POD modes are first extracted from several CFD data sets, using a snapshot POD approach. Then the entire flow field of measured data can be reconstructed using a gappy POD method. The technique is applied to the transonic flow around a civil aircraft type wind tunnel model. The EFD measurements consist in pressure coefficient data from pressure ports or pressure-sensitive paint. It is shown that the complete flow field can be reconstructed from the pressure data with satisfactory accuracy and at relatively low computational cost. The work demonstrates the potential of the POD technique to integrate EFD and CFD data, leading to a combined, validated and complete analysis of the flow under consideration. [less ▲]

Microsatellite Amplification in Plants: Optimization Procedure of Major PCR Components

in Kantartzi, Stella (Ed.) Methods in Molecular Biology™ series: Microsatllites (2013)

The country of residence and migrant transnationalism: how do opportunity structures in countries of residence affect transnational attitudes and behavior of migrant organizations from the African Great Lakes region

in Halm, Dirk; Sezgin, Zeynep (Eds.) Migration and Organized Civil Society: Rethinking national policy (2013)

The relevance of food composition data for nutrition surveys in rural Tibet: pilot study in the context of Kashin-Beck Disease

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2013), 17(1), 32-42

Kashin-Beck disease (KBD) is an endemic and chronic osteochondropathy. This disease principally occurs in the Tibet Autonomous Region and in several provinces of the People’s Republic of China. The ... [more ▼]

Kashin-Beck disease (KBD) is an endemic and chronic osteochondropathy. This disease principally occurs in the Tibet Autonomous Region and in several provinces of the People’s Republic of China. The etiology of the disease remains obscure although environmental factors are assumed to be involved. Diet, in particular, differentiates the rural community, affected by KBD, from the other communities (nomads and city-dwellers), who remain unaffected. In anticipation of a nutrition survey, this study aimed to measure the mineral content (Ca, P, Mg, Fe, Zn, Mn, Cu, Ni, Se, Al, Sr, Mo, Cd, As, Pb, Hg, Cr, and Co) of eight Tibetan staple foods and to compare the results against two food composition tables (FCTs). Foods were sampled in twenty households selected from both an endemic and a non-endemic area of rural Tibet. Ten minerals involved in bone metabolism were measured using atomic and molecular spectrometric methods. Results revealed that a very limited number of food/constituent pairs showed a variation in mineral composition during a single year of testing for a given region. In addition, results showed significant differences in mineral content between the endemic and the non-endemic area, especially for wheat flour. Following our analysis of the mineral content of the Tibetan food samples, results were statistically compared with similar foods listed in two food composition tables: the USDA National Nutrient Database (USDA Food Search for Windows, Version 1.0, database version SR23), and the China Food Composition Table (book 1, 2nd edition). More than 50 to 60% of p-values < 0.05 were highlighted, suggesting the inappropriateness of using FCTs as a reference for nutrition surveys in rural Tibet, and emphasizing the need for analysis of traditional foods. Differences were found to be more or less marked depending on the element considered, and calcium content seemed to show the greatest difference. Although it is obviously too early for definite conclusions to be reached (insufficient number of samples by food and insufficient number of foods analyzed), it seems that the present pilot-study indicates significant discrepancies between measured and tabulated values of the mineral content of certain foods. A more complete survey would therefore seem mandatory. [less ▲]

GFR Estimation Using Standardized Cystatin C in Kidney Transplant Recipients

in American Journal of Kidney Diseases (2013), 61(2), 279-284

Background: The utility of serum cystatin C (SCysC) as a filtration marker in kidney transplantation is uncertain. We took advantage of the recent validation of a reference calibrator for SCysC and of ... [more ▼]

Background: The utility of serum cystatin C (SCysC) as a filtration marker in kidney transplantation is uncertain. We took advantage of the recent validation of a reference calibrator for SCysC and of newly developed CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equations (2012) expressed for use with standardized SCysC level to reassess the performance of SCysC as a filtration marker in kidney transplant recipients. Study Design: Study of diagnostic test accuracy. Setting & Participants: 670 kidney transplant recipients from 3 centers undergoing glomerular filtration rate (GFR) measurements from December 2006 to November 2012. Index Test: Estimated GFR (eGFR) using the 2012 SCysC-based and serum creatinine (SCr)/SCysCbased CKD-EPI equations (eGFRcys and eGFRcr-cys, respectively) and the 2009 SCr-based CKD-EPI equation (eGFRcr), with SCysC and SCr measured at a single laboratory between April 2011 and June 2011. Reference Test: Measured GFR (mGFR) using urinary clearance of inulin. Results: Bias (the difference between mGFR and eGFR) was significantly smaller for eGFRcys and eGFRcr-cys versus eGFRcr ( 2.82 and 0.54 vs 4.4 mL/min/1.73 m2, respectively; P 0.001). Precision (standard deviation of the mean bias) also was better for eGFRcys and eGFRcr-cys versus eGFRcr (12 and 11 vs 13 mL/min/1.73 m2 [P 0.001 for both comparisons]). Accuracy (percentage of GFR estimates within 30% of mGFR) was greater for eGFRcys and eGFRcr-cys versus eGFRcr (81% and 86% vs 75%, respectively [P 0.004 and P 0.001]). Net reclassification index with respect to mGFR of 30 mL/min/1.73 m2 for eGFRcr-cys and eGFRcys versus eGFRcr was 18.8% [95% CI, 8.6%-28.9%] and 22.5% [95% CI, 10.2%-34.9%]. Limitations: Patients were exclusively of European descent; association with transplant outcome was not evaluated. Conclusions: Our data validate the use of both the newly developed SCysC-based and SCr/SCysC-based CKD-EPI equations (2012) in kidney transplant recipients. Both equations perform better than the SCr-based CKD-EPI equation (2009). [less ▲]

Stimulation of the sphenopalatine ganglion (SPG) for cluster headache treatment. Pathway CH-1: A randomized, sham-controlled study.

in Cephalalgia : An International Journal of Headache (2013)

BackgroundThe pain and autonomic symptoms of cluster headache (CH) result from activation of the trigeminal parasympathetic reflex, mediated through the sphenopalatine ganglion (SPG). We investigated the ... [more ▼]

BackgroundThe pain and autonomic symptoms of cluster headache (CH) result from activation of the trigeminal parasympathetic reflex, mediated through the sphenopalatine ganglion (SPG). We investigated the safety and efficacy of on-demand SPG stimulation for chronic CH (CCH).MethodsA multicenter, multiple CH attack study of an implantable on-demand SPG neurostimulator was conducted in patients suffering from refractory CCH. Each CH attack was randomly treated with full, sub-perception, or sham stimulation. Pain relief at 15 minutes following SPG stimulation and device- or procedure-related serious adverse events (SAEs) were evaluated.FindingsThirty-two patients were enrolled and 28 completed the randomized experimental period. Pain relief was achieved in 67.1% of full stimulation-treated attacks compared to 7.4% of sham-treated and 7.3% of sub-perception-treated attacks (p < 0.0001). Nineteen of 28 (68%) patients experienced a clinically significant improvement: seven (25%) achieved pain relief in >/=50% of treated attacks, 10 (36%), a >/=50% reduction in attack frequency, and two (7%), both. Five SAEs occurred and most patients (81%) experienced transient, mild/moderate loss of sensation within distinct maxillary nerve regions; 65% of events resolved within three months.InterpretationOn-demand SPG stimulation using the ATI Neurostimulation System is an effective novel therapy for CCH sufferers, with dual beneficial effects, acute pain relief and observed attack prevention, and has an acceptable safety profile compared to similar surgical procedures. [less ▲]