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"Morvan, A."
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Quantum Information Scrambling on a Superconducting Qutrit Processor
by
Siddiqi, I.
,
Ramasesh, V. V.
,
Morvan, A.
in
Algorithms
,
Circuits
,
CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY
2021
The dynamics of quantum information in strongly interacting systems, known as quantum information scrambling, has recently become a common thread in our understanding of black holes, transport in exotic non-Fermi liquids, and many-body analogs of quantum chaos. To date, verified experimental implementations of scrambling have focused on systems composed of two-level qubits. Higher-dimensional quantum systems, however, may exhibit different scrambling modalities and are predicted to saturate conjectured speed limits on the rate of quantum information scrambling. We take the first steps toward accessing such phenomena, by realizing a quantum processor based on superconducting qutrits (three-level quantum systems). We demonstrate the implementation of universal two-qutrit scrambling operations and embed them in a five-qutrit quantum teleportation protocol. Measured teleportation fidelitiesFavg=0.568±0.001confirm the presence of scrambling even in the presence of experimental imperfections and decoherence. Our teleportation protocol, which connects to recent proposals for studying traversable wormholes in the laboratory, demonstrates how quantum technology that encodes information in higher-dimensional systems can exploit a larger and more connected state space to achieve the resource efficient encoding of complex quantum circuits.
Journal Article
Effect of increasing the proportion of chicory in forage-based diets on intake and digestion by sheep
by
Le Morvan, A.
,
Rochette, Y.
,
Niderkorn, V.
in
Animal Nutritional Physiological Phenomena
,
Animals
,
associative effects
2019
There is a lot of evidence that chicory could be a highly palatable and nutritious source of forage for ruminants, well adapted to climate change and dry conditions in summer, thanks to its resistance to drought and high water content. This study aimed to describe the effect of incorporating chicory to ryegrass or to a ryegrass–white clover mixture on feeding behaviour, digestive parameters, nitrogen (N) balance and methane (CH4) emissions in sheep. In total, three swards of ryegrass, white clover and chicory were established and managed in a manner ensuring the forage use at a constant vegetative stage throughout the experiment. In all, four dietary treatments (pure ryegrass; binary mixture: 50% ryegrass–50% chicory; ternary mixture: 50% ryegrass–25% white clover–25% chicory; and pure chicory) were evaluated in a 4×4 replicated Latin square design with eight young castrated Texel sheep. Each experimental period consisted of an 8-day diet adaptation phase, followed by a 6-day measuring phase during which intake dynamics, chewing activity, digestibility, rumen liquid passage rate, fermentation end-products, N balance and CH4 emissions were determined. Data were analysed using a mixed model and orthogonal contrasts were used to detect the potential associative effects between ryegrass and chicory. The daily voluntary dry matter intake was lower for pure ryegrass than for diets containing chicory (P<0.001) and increased quadratically from 1.39 to 1.74 kg/day with increasing proportion of chicory. Huge positive quadratic effects (P<0.001) between ryegrass and chicory were detected on eating time and eating rate just after feeding indicating an increase of the motivation to eat with mixtures, whereas rumination activity decreased linearly with the proportion of chicory (P<0.001). The organic matter digestibility was similar among treatments (around 80%), but a strong positive quadratic P<0.001) effect was observed on liquid passage rate suggesting that chicory allowed fast particle breakdown in the rumen. Animals fed with the ryegrass–white clover–chicory mixture had the higher urinary N losses (P<0.001), whereas retained N per day or per g N intake was greater when the proportion of chicory was at least 50% (P<0.001) being ~40% greater than for the other treatments. The CH4 yield was lower with pure chicory than with the other treatments (P<0.001) for which emissions were similar. In conclusion, mixing ryegrass and chicory in equal proportions produces a synergy on voluntary intake and an improved N use efficiency likely due to complementarity in chemical composition, increased motivation to eat and faster ruminal particle breakdown.
Journal Article
Effects of elevated CO2 and extreme climatic events on forage quality and in vitro rumen fermentation in permanent grassland
by
Niderkorn, Vincent
,
Decau, Marie-Laure
,
Picon-Cochard, Catherine
in
Agricultural sciences
,
Air temperature
,
Animal production studies
2021
The aim of this study was to analyze changes in botanical and chemical composition, as well as in vitro rumen fermentation characteristics of an upland grassland exposed to climate changes in controlled CO2 concentration, air temperature and precipitation conditions. Grassland was exposed to a future climate scenario coupled with CO2 treatments (390 and 520 ppm) from the beginning of spring. During summer, an extreme climatic event (ECE; 2 weeks of a +6 ∘C increase in temperature, together with severe drought) was applied and then followed by a recovery period. Three cutting dates were considered, i.e. in April, June and November. The results indicate that increases in greenness, nitrogen (N) content and changes in water-soluble carbohydrate profile in association with botanical composition changes for the November cut lead to higher in vitro dry matter degradability (IVDMD) in the rumen. The neutral detergent fiber : nitrogen (NDF:N) ratio appeared to be a key driver of forage quality, which was affected in opposite ways by elevated CO2 and ECE, with a strong impact on rumen fermentation. Atmospheric CO2 concentration in interaction with ECE tended to affect IVDMD, indicating that the effects of elevated CO2 and ECE may partly offset each other. Our findings indicate that the various factors of climate change need to be considered together in order to properly characterize their effects on forage quality and use by ruminants.
Journal Article
Occurrence of associative effects between grasses and legumes in binary mixtures on in vitro rumen fermentation characteristics
by
NIDERKORN, V
,
LE MORVAN, A
,
BAUMONT, R
in
Agricultural sciences
,
alfalfa
,
Analysis of Variance
2011
When animals are fed a grass and legume mixture, digestive interactions can occur in the rumen between the substrates contained in the different plants, and the response of the animal to the combination of forages can differ from the balanced median values of their components considered individually. Our objective was to assess the associative effects between temperate forages in 8 grass-legume binary combinations on in vitro rumen fermentation characteristics to highlight synergies or antagonisms in terms of nutritional and environmental impacts. Two grasses (cocksfoot, CF; ryegrass, RG) and 4 legume species (alfalfa, A; white clover, WC; red clover, RC; sainfoin, SAN) were incubated alone and in grass-legume mixture (1:1, wt/wt) in batches containing buffered rumen fluid during 3.5 and 24 h. For each substrate and each incubation time, parameters describing the degradation of the energetic and nitrogenous compounds and their partition into fermentation end products were measured. Data were subjected to ANOVA using a mixed procedure to test quadratic contrasts. At 3.5 h of incubation, many quadratic effects were observed. The presence of A, WC, or RC in mixtures quadratically increased the NH(3)-N production (up to +28% when compared with the calculated value, P < 0.001), whereas the presence of condensed tannin (CT) activity in SAN considerably decreased it (up to -67%, quadratic effect, P < 0.001) and the N disappearance. To a lesser extent, the presence of SAN reduced the proportion of methane in the gas produced (up to 7%, quadratic effect, P = 0.018). Generally, the degradation of OM and NDF was not stimulated by mixing grass and legume, except for SAN. However, the presence of SAN severely impaired the NDF digestion at the early phase of fermentation. At 24 h of incubation, few associative effects were observed in comparison with those observed at 3.5 h of incubation, but the effect of CT of SAN on N metabolism was still clearly present. This study shows that, among the grass-legume mixtures tested in vitro, only the presence of SAN can interact with the grasses to reduce the degradation of proteins and the production of methane but with a transitory negative effect on fiber digestion.
Journal Article
Frequent moving of grazing dairy cows to new paddocks increases the variability of milk fatty acid composition
2015
The aim of this work was to investigate the variations of milk fatty acid (FA) composition because of changing paddocks in two different rotational grazing systems. A total of nine Holstein and nine Montbéliarde cows were divided into two equivalent groups according to milk yield, fat and protein contents and calving date, and were allocated to the following two grazing systems: a long duration (LD; 17 days) of paddock utilisation on a heterogeneous pasture and a medium duration (MD) of paddock utilisation (7 to 10 days) on a more intensively managed pasture. The MD cows were supplemented with 4 kg of concentrate/cow per day. Grazing selection was characterised through direct observations and simulated bites, collected at the beginning and at the end of the utilisation of two subsequent MD paddocks, and at the same dates for the LD system. Individual milks were sampled the first 3 days and the last 2 days of grazing on each MD paddock, and simultaneously also for the LD system. Changes in milk FA composition at the beginning of each paddock utilisation were highly affected by the herbage characteristics. Abrupt changes in MD milk FA composition were observed 1 day after the cows were moved to a new paddock. The MD cows grazed by layers from the bottom layers of the previous paddock to the top layers of the subsequent new paddock, resulting in bites with high organic matter digestibility (OMD) value and CP content and a low fibre content at the beginning of each paddock utilisation. These changes could induce significant day-to-day variations of the milk FA composition. The milk fat proportions of 16:0, saturated FA and branched-chain FA decreased, whereas proportions of de novo-synthesised FA, 18:0, c9-18:1 and 18:2n-6 increased at paddock change. During LD plot utilisation, the heterogeneity of the vegetation allowed the cows to select vegetative patches with higher proportion of leaves, CP content, OMD value and the lowest fibre content. These small changes in CP, NDF and ADF contents of LD herbage and in OMD values, from the beginning to the end of the experiment, could minimally modify the ruminal ecosystem, production of precursors of de novo-synthesised FA and ruminal biohydrogenation, and could induce only small day-to-day variations in the milk FA composition.
Journal Article
Hepatopulmonary Syndrome and Post-Liver Transplantation Complications: A Case-Control Study
2020
A better knowledge of HPS patient outcomes after LT could influence graft allocation, since there is currently a tendency to attribute better grafts to patients experiencing higher morbidity. [...]the objective of our study was to compare the post-operative outcome in patients with and without HPS following LT, in terms of complications, ventilation parameters, lengths of stay and mortality. Patients were monitored for the first five post-operative days with daily transthoracic echocardiography, pulmonary ultrasound and hepatic Doppler Primary and Secondary Outcomes HPS was defined as an association of cirrhosis, hypoxemia with a p 0 <80 mm Hg on room air and intrapulmonary vasodilatations diagnosed by contrast transthoracic echocardiography and/or a 100% oxygen method. Post-operative complications were included cardiac complications, defined as cardiogenic shock, myocardial infarction, left ventricular systolic dysfunction, elevation of left ventricular filling pressure, pulmonary hypertension, or other complications; respiratory complications that included acute respiratory distress syndrome (ARDS), pulmonary edema, pneumonia, or pleural effusion; surgical complications including peritonitis, perforation, hemoperitoneum, ileus, evisceration, hepatic artery stenosis and thrombosis, portal vein stenosis and thrombosis, splenic vein thrombosis, biliary leak and stricture, bilioma, or cholangitis; infectious complications including septic shock, bacteremia, peritonitis, pneumonia, septic liver, cholangitis, wound infection, fungal infection; neurological complications including hemorrhage, stroke, seizures, confusion; nephrological complications including need for renal replacement therapy; and acute cellular rejection. Five variables known for their association with post-operative complications were entered into the model: age, MELD score on transplantation day, number of RBC units transfused during transplantation, norepinephrine maximal dosage during transplantation, and number of comorbidities among cardiovascular (coronary artery disease, cerebrovascular disease), respiratory (COPD, asthma), renal (need for renal replacement therapy before transplantation or chronic renal insufficiency defined as a creatinine clearance <60 mL/min according to renal function tests or calculated with MDRD formula), diabetes and obesity.
Journal Article
Effects of condensed tannins in wrapped silage bales of sainfoin (Onobrychis viciifolia) on in vivo and in situ digestion in sheep
by
Pourrat, J.
,
Theodoridou, K.
,
Picard, F.
in
Agricultural sciences
,
Ammonia
,
ammonium nitrogen
2012
The objective of this study was to characterize the condensed tannins (CTs) in wrapped silage bales of sainfoin (Onobrychis viciifolia) and examine their potential action on in vivo and in situ digestive characteristics in sheep. Silage was made from sainfoin, cut at two phenological stages. The first phenological stage, at which silage was made, was from the first vegetation cycle at the end of flowering and the second stage silage was made from regrowth, 5 weeks after the first cut, but before flowering. The silages made from the two phenological stages were fed to 12 rumen-fistulated sheep in a crossover design. Of the 12 sheep, six received polyethylene glycol (PEG) to bind with and remove the effects of CT, whereas the other six were dosed with water. Organic matter digestibility, total-tract N digestibility and N (N) balance were measured over 6 days. Kinetic studies were performed on total N, ammonia N (NH3-N) and volatile fatty acids (VFAs) in rumen fluid before and 1.5, 3 and 6 h after feeding. The kinetics of degradation of dry matter and N from Dacron bags suspended in the rumen were also determined. Biological activity of CT (protein-binding capacity) and CT concentration were greater for the silage made from sainfoin at the early flowering stage. Total-tract N digestibility was increased by the addition of PEG (P < 0.001) to the sainfoin silage before flowering (P < 0.001). CTs decreased N excretion in urine (P < 0.05) and increased faecal N excretion (P < 0.001), but had no effect on body N retention, which is beneficial for the animal. Ruminal N degradability was smaller in the presence of active CT (P < 0.001) at both phenological stages; however, soluble N (P = 0.2060) and NH3-N (P = 0.5225) concentrations in rumen fluid remained unchanged. The results of this experiment indicate that CT in the sainfoin retain their ability to affect the nutritive value of preserved forage legumes.
Journal Article
Hepatopulmonary Syndrome and Post-Liver Transplantation Complications: A Case-Control Study
2020
Although liver transplantation (LT) improves survival in cirrhotic patients with hepatopulmonary syndrome (HPS), few data exist concerning post-operative complications in these patients.
To compare complications after LT between patients with and without HPS.
In a case-control study, we retrospectively analyzed all patients who underwent LT in our center from January 2010 to July 2016. We compared cases of identified HPS to controls matched for age, MELD score, comorbidities, red blood cells transfused, and highest dosage of norepinephrine perfused during transplantation.
Among 451 transplanted patients, we identified 71 patients with HPS who could be analyzed. We found a significantly (p<0.001) higher number of post-operative complications in patients with HPS (median 5
3), with more occurrence of cardiac, infectious and surgical complications than in the controls: 39.4%
12.7% (p<0.001), 81.7%
49.3% (p<0.001), and 59.2%
40.1% (p<0.029), respectively. There were also more ICU readmissions at 1 month among HPS patients (10
1, p=0.01). There was no significant difference concerning ventilation data, lengths of ICU or hospital stay (8.5 [range 3-232] and 32 [14-276] days, respectively on the whole cohort) and death in the ICU (4.2% on the whole cohort). The 1-year survival was higher in HPS patients (94.4%
81.1%, p=0.034); there was no difference in 5-year survival.
HPS patients seem to have a higher number of complications in the first month following LT.
Journal Article
Cloning, gene mapping, and functional analysis of a fructan 1-exohydrolase (1-FEH) from Lolium perenne implicated in fructan synthesis rather than in fructan mobilization
by
Van Laere, André
,
Lothier, Jérémy
,
Prud'homme, Marie-Pascale
in
Amino Acid Sequence
,
amino acid sequences
,
Amino acids
2007
Fructans, which are β-(2,1) and/or β-(2,6) linked polymers of fructose, are important storage carbohydrates in many plants. They are mobilized via fructan exohydrolases (FEHs). The cloning, mapping, and functional analysis of the first 1-FEH (EC 3.2.1.153) from Lolium perenne L. var. Bravo is described here. By screening a perennial ryegrass cDNA library, a 1-FEH cDNA named Lp1-FEHa was cloned. The Lp1-FEHa deduced protein has a low iso-electric point (5.22) and it groups together with plant FEHs and cell-wall type invertases. The deduced amino acid sequence shows 75% identity to wheat 1-FEH w2. The Lp1-FEHa gene was mapped at a distal position on the linkage group 3 (LG3). Functional characterization of the recombinant protein in Pichia pastoris demonstrated that it had high FEH activity towards 1-kestotriose, 1,1-kestotetraose, and inulin, but low activity against 6-kestotriose and levan. Like other fructan-plant FEHs, no hydrolase activity could be detected towards sucrose, convincingly demonstrating that the enzyme is not a classic invertase. The expression pattern analysis of Lp1-FEHa revealed transcript accumulation in leaf tissues accumulating fructans while transcript level was low in the photosynthetic tissues. The high expression level of this 1-FEH in conditions of active fructan synthesis, together with its low expression level when fructan contents are low, suggest that it might play a role as a β-(2,1) trimming enzyme acting during fructan synthesis in concert with fructan synthesis enzymes.
Journal Article
Le projet parental à l’épreuve du médical : parcours de soins en AMP et expériences vécues de l’infertilité en France en 2020
2022
À partir d’un échantillon de 1 503 personnes, cette étude s’intéresse aux patients des centres d’assistance médicale à la procréation (AMP) pris en charge en France en 2020 afin d’interroger leur parcours médical comme leurs expériences de l’infertilité dans la vie professionnelle, intime, familiale et conjugale. Le questionnaire en ligne, composé de 178 questions, offre trois grandes familles de résultats : les domaines dans lesquels l’AMP donne satisfaction à une majorité de personnes ; les points de vigilance ; les résultats les plus frappants, notamment l’invisibilité des jeunes et des hommes parmi les patients, le pessimisme quant aux résultats de leur traitement et la difficile relation au corps pour les femmes. L’ensemble des résultats souligne l’importance d’une conception globale des patients infertiles, hommes et femmes, jeunes et moins jeunes, au-delà de la seule dimension médicale, pour une prise en compte aussi bien psychologique, sociale que professionnelle, sous-tendue par une équipe d’accompagnants élargie.
Journal Article