3,093 research outputs found
NUCLEAR REFRACTIVE EFFECTS IN NUCLEUS-NUCLEUS SCATTERING AT INTERMEDIATE ENERGIES
We present theoretical evidence for the occurence of a nuclear rainbow effect in C12+ C12 elastic scattering at 1.016 GeV
Strong obstruction of the Berends-Burgers-van Dam spin-3 vertex
In the eighties, Berends, Burgers and van Dam (BBvD) found a nonabelian cubic
vertex for self-interacting massless fields of spin three in flat spacetime.
However, they also found that this deformation is inconsistent at higher order
for any multiplet of spin-three fields. For arbitrary symmetric gauge fields,
we severely constrain the possible nonabelian deformations of the gauge algebra
and, using these results, prove that the BBvD obstruction cannot be cured by
any means, even by introducing fields of spin higher (or lower) than three.Comment: 19 pages, no figur
L-Grassf: A New Model for Simulating the Genetic Environment Interactions on the Reproductive Phenology of Grasses
Predicting the reproductive phenology in perennial grasses is a major concern because it determines the quantity and quality of forage. It varies a lot depending on site, year and cultivar. Projections of future climates suggest significant changes in seasonal temperature pattern, with new combinations of temperature and photoperiod, whose consequences on the floral induction of perennial grasses are unknown. L-GrassF is a new Functional Structural Plant Model simulating genetic variability of the phenology of perennial ryegrass in order to better understand the perenniality of grasslands and better anticipate the effects of climate change. L-GrassF stems from a previous model (L-Grass) and now simulates the reproductive stages by integrating the interactions between vegetative growth, floral induction and reproductive organ development. The sensitivity analysis of a set of parameters was studied in the range of oceanic temperate climate conditions, on several European cultivars. It was further calibrated and validated on two independent datasets from the French Variety and Seed Study and Control Group (GEVES), which include the observations of heading dates for seven cultivars of Lolium perenne grown in six French locations between 2001 and 2017
Les effets pro-arythmiques des médicaments
RésuméLes effets pro-arythmiques des médicaments sont fréquents et graves, et sont associés à une surmortalité non négligeable. La polymédication augmente le nombre d’effets indésirables et d’interactions graves voire mortelles. Certains sont facilement évitables. Cependant, au-delà de l’allongement de l’intervalle QT, d’autres mécanismes peuvent avoir un rôle majeur comme les dysfonctions du RyR2, responsable d’arythmie calcium-dépendantes par surcharge calcique intracellulaire, avec apparition de post-dépolarisations tardives, sans modifications de l’intervalle QT. Les bloqueurs des canaux sodiques sont également un problème sérieux de part le risque de démasquer ou d’aggraver une dysfonction du canal sodique chez des patients atteints de syndrome de Brugada asymptomatique ou non. Leur dépistage à un stade précoce du développement des médicaments peut avoir un intérêt majeur.SummaryThe cardiac safety of new and marketed drugs is a major concern for public authorities, patients, physicians as well as pharmaceutical companies. Letal adverse drug reactions are indeed a leading cause of death worldwide and increase at a greater rate than the increase in total hospital admission. The increasing use of polypharmacy in current clinical practice is also associated to a growing number of side effects and interactions leading to fatal adverse events. Measurement of the QT interval is an established, albeit incomplete, approach to assess the proarrhythmic risk of a drug. Ventricular arrhythmia (VA) can be caused by a QT-prolonging drug inducing abnormal repolarization of the action potential (AP) of ventricular cardiomyocytes. Emerging evidence, derived from recent understanding of these mechanisms and of similar mechanisms reported for heart failure (HF), suggest that diastolic Ca2+ leak from the sarcoplasmic reticulum (SR) related to RyR2 dysfunction can induce Ca2+ dependent arrhythmia. In this report, we review mechanisms underlying drug-induced arrhythmogenic effects and Ca2+ dependent arrhythmia, and, for the latter, we discuss some of the issues associated to worsening of cardiac arrhythmias
Early assessment of glucose abnormalities during continuous glucose monitoring associated with lung function impairment in cystic fibrosis patients
AbstractBackgroundCystic fibrosis-related diabetes (CFRD) is correlated with a decline in lung function. Under certain circumstances, oral glucose tolerance test (OGTT) screening, used to diagnose CFRD, fails to reveal early glucose tolerance abnormalities. In this situation, continuous glucose monitoring (CGM) could be a useful tool for evaluating early abnormalities of glucose tolerance in CF patients. We aimed to study the CGM glucose profile in CF patients with normal OGTT screening results and to evaluate lung function and nutritional status according to the CGM glucose profile.MethodsWe assessed glycemic control, the CGM glucose profile, nutritional status, lung function antibiotic courses and colonization (P. aeruginosa and S. aureus) in CF patients, aged 10years and over, with normal screening OGTT results (blood glucose at T120min<7.8mmol/l). Two groups were identified according to the max CGM glucose value: Group 1<11mmol/l and Group 2≥11mmol/l.ResultsAmong the 38 patients with normal OGTT, 12 (31.6%) were in Group 2. Compared to Group 1, Group 2 patients exhibited a significant impairment in lung function: FEV1, 68.2±25.6% vs. 87.3±17%, p=0.01 and FVC, 86.1%±19.4% vs. 99.3%±13.4%, p=0.021, as well as a higher rate of colonization by P. aeruginosa: 83.3% vs. 44%, p=0.024. Nevertheless, there were no differences in nutritional status (BMI standard deviation score: p=0.079; prealbumin: p=0.364).ConclusionsCGM reveals early abnormalities of glucose tolerance that remain undiagnosed by OGTT screening and are associated with worse lung function and a higher prevalence of P. aeruginosa colonization in patients with CF.Clinical trial registration number: NCT00476281
Invasive Ductular Reaction Operates Hepatobiliary Junctions upon Hepatocellular Injury in Rodents and Humans.
Ductular reaction (DR) is observed in virtually all liver diseases in both humans and rodents. Depending on the injury, DR is confined within the periportal area or invades the parenchyma. On severe hepatocellular injury, invasive DR has been proposed to arise for supplying the liver with new hepatocytes. However, experimental data evidenced that DR contribution to hepatocyte repopulation is at the most modest, unless replicative capacity of hepatocytes is abrogated. Herein, we proposed that invasive DR could contribute to operating hepatobiliary junctions on hepatocellular injury. The choline-deficient ethionine-supplemented mouse model of hepatocellular injury and human liver samples were used to evaluate the hepatobiliary junctional role of the invasive form of DR. Choline-deficient ethionine-supplemented-induced DR expanded as biliary epithelium into the lobule and established new junctions with the canaliculi. By contrast, no new ductular-canalicular junctions were observed in mouse models of biliary obstructive injury exhibiting noninvasive DR. Similarly, in humans, an increased number of hepatobiliary junctions were observed in hepatocellular diseases (viral, drug induced, or metabolic) in which DR invaded the lobule but not in biliary diseases (obstruction or cholangitis) in which DR was contained within the portal mesenchyme. In conclusion, our data in rodents and humans support that invasive DR plays a hepatobiliary junctional role to maintain structural continuity between hepatocytes and ducts in disorders affecting hepatocytes
FAO/WHO GIFT (Global Individual Food consumption data Tool): a global repository for harmonised individual quantitative food consumption studies
Knowing who eats what, understanding the various eating habits of different population groups, according to the geographical area, is critical to develop evidence-based policies for nutrition and food safety. The FAO/WHO Global Individual Food consumption data Tool (FAO/WHO GIFT) is a novel open-access online platform, hosted by FAO and supported by WHO, providing access to harmonised individual quantitative food consumption (IQFC) data, especially in low- and middle-income countries (LMIC). FAO/WHO GIFT is a growing repository, which will serve as the global FAO/WHO hub to disseminate IQFC microdata. Currently five datasets from LMIC are available for dissemination, and an additional fifty datasets will be made available by 2022. To facilitate the use of these data by policy makers, ready-to-use food-based indicators are provided for an overview of key data according to population segments and food groups. FAO/WHO GIFT also provides an inventory of existing IQFC data worldwide, which currently contains detailed information on 188 surveys conducted in seventy-two countries. In order for end-users to be able to aggregate the available data, all datasets are harmonised with the European Food Safety Authority's food classification and description system FoodEx2 (modified for global use). This harmonisation is aimed at enhancing the consistency and reliability of nutrient intake and dietary exposure assessments. FAO/WHO GIFT is developed in synergy with other global initiatives aimed at increasing the quality, availability and use of IQFC data in LMIC to enable evidence-based decision-making and policy development for better nutrition and food safety
Fast-TIPL Occurs for Salient Images without a Memorization Requirement in Men but Not in Women
Recent research of task-irrelevant perceptual learning (TIPL) demonstrates that stimuli that are consistently presented at relevant point in times (e.g. with task-targets or rewards) are learned, even in the absence of attention to these stimuli. However, different research paradigms have observed different results for how salient stimuli are learned; with some studies showing no learning, some studies showing positive learning and others showing negative learning effects. In this paper we focused on how the level of processing of stimuli impacts fast-TIPL. We conducted three different experiments in which the level of processing of the information paired with a target was manipulated. Our results indicated that fast-TIPL occurs when participants have to memorize the information presented with the target, but also when they just have to process this information for a secondary task without an explicit memorization of those stimuli. However, fast-TIPL does not occur when participants have to ignore the target-paired information. This observation is consistent with recent models of TIPL that suggest that attentional signals can either enhance or suppress learning depending on whether those stimuli are distracting or not to the subjects' objectives. Our results also revealed a robust gender effect in fast-TIPL, where male subjects consistently show fast-TIPL, whereas the observation of fast-TIPL is inconsistent in female subjects
Could Dietary Goals and Climate Change Mitigation Be Achieved Through Optimized Diet? The Experience of Modeling the National Food Consumption Data in Italy
Objective: The aim of this study is to define a healthy and sustainable diet model with low GHGE, fulfilling dietary requirements, and considering current Italian food consumption patterns. Design: A duly designed database was developed, linking food nutritional composition and GHGE based on 921 food items consumed in Italy according to the last national food consumption survey (INRAN-SCAI 2005–2006). Linear programming was used to develop new diet plans separately for males and females, aged 18–60 years (n = 2,098 subjects), in order to minimize GHGE. The program is based on dietary goals and acceptability constraints as well as on 13 nutrient requirement constraints aiming to reach a healthy and acceptable diet for the Italian population. Results: Diet optimization resulted in a nutritionally adequate pattern minimizing GHGE values (4.0 vs. 1.9 kg CO2e/day for males and 3.2 vs. 1.6 kg CO2e/day for females). In both sexes, the nutrient intake of the optimized diet was at the established lower bound for cholesterol and calcium and at the established upper bound for free sugar and fiber. In males, intake of zinc was at the established lower bound whereas iron was at the established upper bound. Consumption of red meat and fruit and vegetables was at the established lower and upper bound, respectively, in both males and females. Despite the decrease in meat consumption, especially red meat, in the optimized diet with respect to the observed diet, levels of iron intake in females increased by 10% (10.3 vs. 11.3 mg/day) but remained below the adequate intake established in Italian national DRIs. Conclusions: An attainable healthy dietary pattern was developed that would lead to the reduction of GHGE by 48% for males and by 50% for females with respect to current food consumption in the Italian adult population. Health-promoting dietary patterns can substantially contribute to achieve related Sustainable Development Goals
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