Showing papers by "Université Nantes Angers Le Mans published in 2012"
TL;DR: Higher vitamin D dietary intake was associated with a lower risk of developing Alzheimer's disease among older women, and being in the highest quintile of vitamin D Dietary intakes wasassociated with a higher risk of AD.
Abstract: BACKGROUND: Hypovitaminosis D is associated with cognitive decline among older adults. The relationship between vitamin D intakes and cognitive decline is not well understood. Our objective was to determine whether the dietary intake of vitamin D was an independent predictor of the onset of dementia within 7 years among women aged 75 years and older. METHODS: Four hundred and ninety-eight community-dwelling women (mean, 79.8 +/- 3.8 years) free of vitamin D supplements from the EPIDemiology of OSteoporosis Toulouse cohort study were divided into three groups according to the onset of dementia within 7 years (ie, no dementia, Alzheimer's disease [AD], or other dementias). Baseline vitamin D dietary intakes were estimated from self-administered food frequency questionnaire. Age, body mass index, initial cognitive performance, education level, physical activity, sun exposure, disability, number of chronic diseases, hypertension, depression, use of psychoactive drugs, and baseline season were considered as potential confounders. RESULTS: Women who developed AD (n = 70) had lower baseline vitamin D intakes (mean, 50.3 +/- 19.3 mug/wk) than nondemented (n = 361; mean intake = 59.0 +/- 29.9 mug/wk, p = .027) or those who developed other dementias (n = 67; mean intake = 63.6 +/- 38.1 mug/wk, p = .010). There was no difference between other dementias and no dementia (p = .247). Baseline vitamin D dietary intakes were associated with the onset of AD (adjusted odds ratio = 0.99 [95% confidence interval = 0.98-0.99], p = .041) but not with other dementias (p = .071). Being in the highest quintile of vitamin D dietary intakes was associated with a lower risk of AD compared with the lower 4 quintiles combined (adjusted odds ratio = 0.23 [95% confidence interval = 0.08-0.67], p = .007). CONCLUSIONS: Higher vitamin D dietary intake was associated with a lower risk of developing AD among older women.
175 citations
TL;DR: A new fibrosis classification that synchronously combines two fibrosis tests was as accurate as successive SAFE or BA, while providing an entirely noninvasive (0% liver biopsy) and more precise (six versus two or three fibrosis classes) fibrosis diagnosis.
120 citations
TL;DR: The results show that the contamination levels in food and therefore the exposure of the general French population to PCDD/Fs and PCBs have declined since the last evaluation, and show the efficiency of the European risk management measures which came into force after these evaluations.
103 citations
TL;DR: It is found that a larvicide spraying at regular time intervals acted as a preventive measure against mosquito emergence, and that such a strategy was more efficient than spraying only when the abundance of host-seeking females reached a given threshold.
81 citations
TL;DR: In this article, the uplift capacity of helical anchors normally increases with the number of the helical plates and the rate of capacity gain is variable, considering that the disturbance caused by the anchor installatio...
Abstract: The uplift capacity of helical anchors normally increases with the number of helical plates. The rate of capacity gain is variable, considering that the disturbance caused by the anchor installatio...
76 citations
TL;DR: Phelipanche ramosa germination was strongly and specifically triggered by isothiocyanates, indicating that 2-PEITC, in particular, plays a key role in the B. napus-P.
Abstract: Phelipanche ramosa is a major parasitic weed of Brassica napus The first step in a host-parasitic plant interaction is stimulation of parasite seed germination by compounds released from host root
73 citations
TL;DR: In this paper, the authors investigated the impact of the amount of steam (100, 200 and 400 ml) during baking on the crust features and water diffusivity of fresh bread.
60 citations
TL;DR: In this article, the experimental conditions of a representative odour extraction method were determined after testing eight SPME, dynamic headspace and purge-and-trap procedures, and the most suitable method to obtain representative extract of cider odour.
58 citations
TL;DR: In this paper, the influence of the properties (firmness and fat content) of a solid processed model cheese on in vivo aroma release while considering the role of the in-mouth process during both mastication and post-swallowing steps, and the hydrophobicity of aroma compounds, on a large number of well characterized subjects.
Abstract: The aim of this work was to clarify the influence of the properties (firmness and fat content) of a solid processed model cheese on in vivo aroma release while considering the role of the in-mouth process during both mastication and post-swallowing steps, and the hydrophobicity of aroma compounds, on a large number of well characterized subjects. In vivo aroma release was studied on 44 subjects who freely consumed six processed model cheeses flavoured with the same concentration of nonan-2-one and ethyl propanoate. Globally, an increase in firmness induced an increase in chewing duration, amount of saliva incorporated into the food bolus, total amount of aroma released and rate of release. The kinetics of release clearly differed between the two aroma compounds. Ethyl propanoate presented a higher release rate for firmer cheese and was more released during the mastication step, whereas nonan-2-one was more released during the post-swallowing step and more persistent in the mouth, due to its higher hydrophobicity. Consuming cheeses with a higher fat content led to a higher amount of product remaining in the mouth after swallowing, a lower amount of nonan-2-one released and a longer persistence of nonan-2-one in the breath. The results could be helpful to better understand the relative influence of the parameters related to products and subjects in order to reformulate foods with good sensory acceptability. Copyright (C) 2012 John Wiley & Sons, Ltd.
57 citations
TL;DR: Patulin induced acute neurotoxicity on Diptera larvae, indicating the interest of this bioassay as an additional tool for detection of this major mycotoxin in crude extracts.
48 citations
TL;DR: It can be concluded that the origin of EAE exacerbation in PrPc-ablated mice resides in the absence of the prion protein in the central nervous system, highlighting the critical role ofPrPc in maintaining the integrity of the CNS in situations of stress, especially during a neuroinflammatory insult.
Abstract: Background
The cellular prion protein (PrPc) is a host-encoded glycoprotein whose transconformation into PrP scrapie (PrPSc) initiates prion diseases. The role of PrPc in health is still obscure, but many candidate functions have been attributed to the protein, both in the immune and the nervous systems. Recent data show that experimental autoimmune encephalomyelitis (EAE) is worsened in mice lacking PrPc. Disease exacerbation has been attributed to T cells that would differentiate into more aggressive effectors when deprived of PrPc. However, alternative interpretations such as reduced resistance of neurons to autoimmune insult and exacerbated gliosis leading to neuronal deficits were not considered.
TL;DR: The impact of soil on the bioavailability of indicator PCBs was assessed by means by a relative bioavailability (RBA) trial, in which their deposition in egg yolk and in abdominal fat, in response to their ingestion through contaminated-soil and through spiked-oil were compared.
TL;DR: Once the subjects have achieved the free sorting of the stimuli, they are instructed to organize, step by step, the stimuli into a hierarchical structure thus giving more insight into the similarities among products.
TL;DR: In this article, a Lagrangian-based large-strain analysis framework was used to examine the nature of strain and kinematic nonuniformity within shear bands in sands.
Abstract: SUMMARY
A methodology has been developed to extend the incremental (Eulerian) Digital Image Correlation (DIC) technique to enable a Lagrangian-based large-strain analysis framework to examine the nature of strain and kinematic nonuniformity within shear bands in sands. Plane strain compression tests are performed on dense sands in an apparatus that promotes unconstrained persistent shear band formation. DIC is used to capture incremental, grain-scale displacements in and around shear bands. The performance of the developed accumulation algorithm is validated by comparing accumulated displacements with two sources of reference measurements. A comparison between large and infinitesimal rotation is performed, demonstrating the nature of straining within shear bands in sands and the necessity of using a finite strain formulation to characterize ensuing behavior. Volumetric strain variation along the shear band is analyzed throughout macroscopic postpeak deformation. During softening, volumetric activity within the shear band is purely dilative. During the global critical state, the shear band material is seen on the average to deform at zero volumetric strain; however, locally, the sand is seen to exhibit significant nonzero volumetric strain, putting into question the current definition of critical state. At the softening-critical state transition, a spatially periodic pattern of alternating contraction and dilation along the shear band is evidenced, and a preliminary evaluation indicates that the periodicity appears to be a physical phenomenon dictated only in part by median grain size. Copyright © 2011 John Wiley & Sons, Ltd.
TL;DR: Brachyuran crabs of the family Bythograeidae are endemic to deep-sea hydrothermal vents and represent one of the most successful groups of macroinvertebrates that have colonized this extreme environment.
Abstract: Brachyuran crabs of the family Bythograeidae are endemic to deep-sea hydrothermal vents and represent one of the most successful groups of macroinvertebrates that have colonized this extreme environment. Occurring worldwide, the family includes six genera (Allograea, Austinograea, Bythograea, Cyanagraea, Gandalfus, and Segonzacia) and fourteen formally described species. To investigate their evolutionary relationships, we conducted Maximum Likelihood and Bayesian molecular phylogenetic analyses, based on DNA sequences from fragments of three mitochondrial genes (16S rDNA, Cytochrome oxidase I, and Cytochrome b) and three nuclear genes (28S rDNA, the sodium–potassium ATPase a-subunit ‘NaK’, and Histone H3A). We employed traditional concatenated (i.e., supermatrix) phylogenetic methods, as well as three recently developed Bayesian multilocus methods aimed at inferring species trees from potentially discordant gene trees. We found strong support for two main clades within Bythograeidae: one comprising the members of the genus Bythograea; and the other comprising the remaining genera. Relationships within each of these two clades were partially resolved. We compare our results with an earlier hypothesis on the phylogenetic relationships among bythograeid genera based on morphology. We also discuss the biogeography of the family in the light of our results. Our species tree analyses reveal differences in how each of the three methods weighs conflicting phylogenetic signal from different gene partitions and how limits on the number of outgroup taxa may affect the results.
TL;DR: Exposure to the BTV-8 virus under natural conditions in previously naive dairy herds notified after clinical suspicion during the 2007 epizootic was associated with an increase in the occurrence of abortions, regardless of the stage of pregnancy.
TL;DR: Two steroids, namely 5 α-androstane-3β,17α-diol and 5α- androst-2-en-17-one were concluded to be compatible with such a definition and which could be finally usable for screening purpose of AED abuse in cattle.
Abstract: The use of anabolic steroids as growth promoters for meat-producing animals is banned within the European Union However, screening for the illegal use of natural steroid hormones still represents a difficult challenge because of the high interindividual and physiological variability of the endogenous concentration levels in animals In this context, the development of untargeted profiling approaches for identifying new relevant biomarkers of exposure and/or effect has been emerging for a couple of years The present study deals with an untargeted metabolomics approach on the basis of GC-MS aiming to reveal potential biomarkers signing a fraudulent administration of 4-androstenedione (AED), an anabolic androgenic steroid chosen as template After a sample preparation based on microextraction by packed sorbent, urinary profiles of the free and deglucurono-conjugates urinary metabolites were acquired by GC-MS in the full-scan acquisition mode Data processing and chemometric procedures highlighted 125 ions, allowing discrimination between samples collected before and after an administration of 4-AED After a first evaluation of the signal robustness using additional and independent non-compliant samples, 17 steroid-like metabolites were pointed out as relevant candidate biomarkers All these metabolites were then monitored using a targeted GC-MS/MS method for an additional assessment of their capacity to be used as biomarkers Finally, two steroids, namely 5α-androstane-3β,17α-diol and 5α-androst-2-en-17-one, were concluded to be compatible with such a definition and which could be finally usable for screening purpose of AED abuse in cattle
TL;DR: In this article, the effect of multiple-axle loadings is simplified and taken into account via load equivalency factors using Miner's Law, and a method for the computation of the fatigue life of bituminous mixtures under multipleaxle configurations that couples a structural approach and a material-based approach is presented.
Abstract: The fatigue damage caused by multiple-axle configurations is a key issue for pavement design. The standard fatigue test consists of the application of a continuous sinusoidal signal on a specimen, which enables the fatigue life to be described as a function of the strain level. For more complex loading signals, additional parameters were found to have an influence on the fatigue life of bituminous mixtures. In the French design method, the effect of multiple-axle loadings is simplified and taken into account via load equivalency factors using Miner's Law. In this article, we present a method for the computation of the fatigue life of bituminous mixtures under multiple-axle configurations that couples a structural approach and a material-based approach. The structural approach consists of a parametric study of real loading signals that enables the computation of the independent shape parameters characterising a loading signal. An experimental plan whose variables are the independent shape parameters was th...
TL;DR: In this paper, a triaxial erodimeter was used to study the suffusion process by using a multichannel optical sensor in order to characterize precisely the initiation and development of suffusion processes.
Abstract: An experimental program was set up to study the suffusion process by using a triaxial erodimeter developed in our laboratory. This device is equipped with a multichannel optical sensor in order to characterize precisely the initiation and development of suffusion process. With the objective to characterize the erodibility of clayey sand, tests were performed under either flow-rate-controlled or hydraulic-gradient-controlled conditions. The test analysis allows distinguishing three steps. First, suffusion of a small quantity of clay is detected on downstream. In flow-rate-controlled conditions, this suffusion is immediately followed by a high increase of the hydraulic gradient which continues during the second step. The second step is characterized by very low amount of particles in the effluent. During the third step, high suffusion of clay appears and induces erosion of clay and sand. The results reveal the necessity to take into account the evolutions of hydraulic gradient (or pressure gradient) and also the evolutions of velocity (or flow rate) to represent the hydraulic loading. The analysis based on energy expended by fluid flow and eroded mass permits to characterize the soil sensitivity to clay suffusion and clayey sand erosion for tests under the two types of hydraulic loading.
27 Aug 2012
TL;DR: In this article, the effect of angularity of coarse fraction grains on suffusion was studied on different clayey sand types and the results showed that the angularity may contribute to increase the erosion resistance of the tested soils by a factor of 5.
Abstract: In earth structures and their foundations, two types of erosion can be distinguished: interface erosion and suffusion. This paper deals with suffusion process also named internal instability, which takes place inside the soil matrix. In this process, finer particles of a soil migrate within its own pore spaces. These fine particles can be cohesionless particles or clay particles. With the objective to study the effect of angularity of coarse fraction grains on suffusion a series of tests was performed on different clayey sand. Three sand type samples were tested which are different by the grain size distribution and also by the angularity of grains. A specific triaxial device was used in order to force fluid through the samples in downward direction under constant hydraulic gradients. It is shown that the angularity of coarse fraction grains may contribute to increase the erosion resistance of the tested soils by a factor of 5. Moreover for the tested soils, the grain shape has an effect on hydraulic conductivity decrease. The angularity of coarse fraction grains may intensify the geometric blocking of eroded clay particles. Finally a study is conducted to compare the different ways to characterize the angularity of grains: by an analysis of grain pictures, by using an angulometer or by measuring the internal friction angle.
TL;DR: PLS discriminant analysis is compared with other methods, and results are illustrated through a case study, to investigate the stability of the various methods using assessors’ re-sampling and confidence ellipses.
TL;DR: In this article, an experimental device designed around the transmission of bulk waves has been developed, which is able to take into account specimen size, center frequency and ease of use, and the studied mixes herein are composed of wet shotcrete, dry shotcrete and concrete that has been formed and manually set.
TL;DR: To assess the prevalence of and risk factors for Raynaud's phenomenon in a French working population characterized by various levels of exposure to work‐related constraints, a large number of patients were diagnosed with RP.
Abstract: Objective
To assess the prevalence of and risk factors for Raynaud's phenomenon (RP) in a French working population characterized by various levels of exposure to work-related constraints.
Methods
The study population comprised 3,710 workers (2,161 men and 1,549 women) who were followed up by 83 occupational physicians and were representative of the region's workforce. RP, as diagnosed by a questionnaire and a standardized interview, was defined as the occurrence of at least occasional attacks of finger blanching triggered by exposure to environmental cold during the previous 12 months. Personal factors and work exposure were assessed by self-administered questionnaires. The associations between RP and personal and occupational factors were analyzed using logistic regression modeling.
Results
A total of 87 cases of RP (56 women and 31 men) were diagnosed. The population-based annual prevalence rates of RP were 3.6% (95% confidence interval [95% CI] 2.7–4.5%) for women and 1.4% (95% CI 0.9–1.9%) for men. Women had a higher risk of RP (odds ratio [OR] 2.1 [95% CI 1.3–3.4]) and the risk decreased continuously with body mass index (OR for 1-kg/m2 increment 0.87 [95% CI 0.81–0.94]). The risk of RP increased consistently but moderately with age after 35 years (ORs ranging from 2.0 [95% CI 1.1–3.8] to 2.9 [95% CI 1.6–5.2]). Among the work-related factors studied, RP was associated with an exposure to a cold environment or objects (OR 2.2 [95% CI 1.0–4.6]), a high repetitiveness of a task (OR 1.7 [95% CI 1.0–2.7]), a high psychological demand at work (OR 1.7 [95% CI 1.0–2.7]), and low support from supervisors (OR 2.4 [95% CI 1.5–3.8]).
Conclusion
Personal and work-related factors were associated with RP, with a clear difference between the sexes. Work-related psychosocial stressors played a significant role independently of biomechanical and environmental exposure.
TL;DR: In this article, the effect of angularity of coarse fraction grains on the internal instability of the soil skeleton is investigated and it is shown that the angularity may contribute to increase the erosion resistance of the tested soils by a factor of 5.
Abstract: This paper deals with suffusion process also named internal instability, which takes place inside the soil skeleton. In this process, finer particles of a soil migrate within its own pore spaces. These fine particles can be cohesionless particles or clay particles. With the objective to study the effect of angularity of coarse fraction grains on suffusion a series of tests was performed on different clayey sand. Three coarse fraction type samples were tested which are different by the grain size distribution and also by the angularity of grains. A specific triaxial device was used in order to force fluid through the samples in downward direction under constant hydraulic gradients.It is shown that the angularity of coarse fraction grains may contribute to increase the erosion resistance of the tested soils by a factor of 5. Moreover for the tested soils, the grain shape has an effect on hydraulic conductivity decrease. The angularity of coarse fraction grains may intensify the geometric blocking of detached clay particles.Finally a study is conducted to compare the different ways to characterize the angularity of grains: by an analysis of grain pictures, by using an angulometer or by measuring the internal friction angle.
TL;DR: In this article, the authors present a study on the impact of the duration of the baking plateau on staling kinetics in the case of bread crumbs made of sourdough; it follows Le-Bail et al.
Abstract: This paper presents a study on the impact of the duration of the baking plateau on staling kinetics in the case of bread crumb made of sourdough; it follows Le-Bail et al. Journal of Cereal Science 50:235–240, (2009)a previous study proposed by Le-Bail et al. Journal of Cereal Science 50:235–240, (2009) on the impact of heating rate during baking on staling parameters. Degassed bread dough was baked in a miniaturized baking system with baking plateau of 0, 4, and 8 min at 98 °C corresponding to a total baking time of 10, 14 and 18 min respectively (simulating from underbaked to fully baked bread). Results showed that longer baking time resulted in the higher Young’s modulus of the baked dough at the end of staling was. It was observed as in Le-Bail et al. Journal of Cereal Science 50:235–240, (2009) that the crystallization of amylopectin occurred a few days before the hardening of the baked crumb during staling. The amount of freezable water decreased during staling (over 10 days period), which was in agreement with the increase in amylopectin crystallites during staling which trap water. The amount of soluble amylose increased with increasing duration of the baking plateau at 98 °C, indicating that for prolonged baking, an increasing amount of amylose is leached outside of the starch granules. This was proposed as an explanation for the higher Young’s modulus of the crumb at the end of staling.
TL;DR: The average BTV-8 exposure in naïve herds led to major losses and the episode of decreased fertility is likely due to a combination of the effect of the infection at different stages of conception and early pregnancy and the delayed exposure of cows due to the spreading of the virus within herds.
TL;DR: The peak Flu-OR during the pandemic significantly exceeded a 15% critical threshold in almost half of the ICUs, with an uneven distribution with time, geographical areas and between University and non-University hospitals.
Abstract: The specific burden imposed on Intensive Care Units (ICUs) during the A/H1N1 influenza 2009 pandemic has been poorly explored. An on-line screening registry allowed a daily report of ICU beds occupancy rate by flu infected patients (Flu-OR) admitted in French ICUs. We conducted a prospective inception cohort study with results of an on-line screening registry designed for daily assessment of ICU burden. Among the 108 centers participating to the French H1N1 research network on mechanical ventilation (REVA) - French Society of Intensive Care (SRLF) registry, 69 ICUs belonging to seven large geographical areas voluntarily participated in a website screening-registry. The aim was to daily assess the ICU beds occupancy rate by influenza-infected and non-infected patients for at least three weeks. Three hundred ninety-one critically ill infected patients were enrolled in the cohort, representing a subset of 35% of the whole French 2009 pandemic cohort; 73% were mechanically ventilated, 13% required extra corporal membrane oxygenation (ECMO) and 22% died. The global Flu-OR in these ICUs was only 7.6%, but it exceeded a predefined 15% critical threshold in 32 ICUs for a total of 103 weeks. Flu-ORs were significantly higher in University than in non-University hospitals. The peak ICU burden was poorly predicted by observations obtained at the level of large geographical areas. The peak Flu-OR during the pandemic significantly exceeded a 15% critical threshold in almost half of the ICUs, with an uneven distribution with time, geographical areas and between University and non-University hospitals. An on-line assessment of Flu-OR via a simple dedicated registry may contribute to better match resources and needs.
TL;DR: Thermogravimetric analysis (TGA) results show that an increase in the final residue and decrease in degradation temperature on both methods of treated wood compared to untreated wood.
TL;DR: Evidence is provided that circulating MPs from patients with OSA induce ex vivo vascular hyperreactivity with the obligatory role of the endothelium and subtle interactions between the nitric oxide and cyclooxygenase pathways and metabolites.
Abstract: Obstructive sleep apnea (OSA) is characterized by repetitive apnea-hypopnea cycles during sleep associated with oxygen desaturation and sleep disruption. We evaluated the role of circulating microparticles (MPs) from patients with OSA in the regulation of vascular function. MPs from whole blood from patients with OSA or control subjects were injected i.v. into mice. Injection of MPs from patients with OSA induced ex vivo vascular hyperreactivity in aortas with functional endothelium but, in contrast, hyporeactivity in vessels without functional endothelium. Vascular hyperreactivity was blunted in the presence of a nitric oxide synthase inhibitor alone or combined with the cyclooxygenase inhibitor indomethacin. MPs from patients with OSA reduced endothelial nitric oxide synthase activity and nitric oxide production, increased aortic cyclooxygenase-1 and cyclooxygenase-2 expression, and increased thromboxane A(2) and prostacyclin production. Blockade of thromboxane A(2) receptor did not affect the serotonin response in arteries from OSA MP-treated mice. A superoxide dismutase mimetic reduced the vascular hyperreactivity induced by MPs from patients with OSA but had no effect on contraction in vessels from control and non-OSA MP-treated mice. These data provide evidence that circulating MPs from patients with OSA induce ex vivo vascular hyperreactivity with the obligatory role of the endothelium and subtle interactions between the nitric oxide and cyclooxygenase pathways and metabolites. These results highlight the participation of MPs in vascular dysfunction associated with OSA.
TL;DR: In this paper, the effect of relative humidity (RH) and temperature on the microbial behavior of Escherichia coli O157:H7 on lettuce was investigated and a Gamma-concept model was developed to develop a specific growth rate (SGR) with high coefficients of determination.
Abstract: The effect of relative humidity (RH) and temperature on the microbial behavior of Escherichia coli O157:H7 on lettuce was investigated. Experimental data obtained under different combined conditions of RH (60, 70, and 80%) and temperature (15, 25, and 35°C) were fitted into the Logistic model with delay to estimate specific growth rate (SGR) with high coefficients of determination (R
2s >0.98). The estimated SGR values were used to develop a Gamma-concept model. Then, several statistic characteristics were employed to verify the performance and reliability of the developed model, which demonstrated that the predictive model was not biased and had high accuracy in prediction. Besides, the analysis of relative importance of temperature and RH indicated that temperature is much more influential on the growth of E. coli O157:H7 on lettuce than the ambient RH changes.