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In Europe, organic food must comply with specific regulations which do not include nutritional criteria. The ability of organic food to meet the nutritional needs of children is not assessed. This narrative review discusses the nutritional composition (macronutrients, micronutrients) of organic food compared with conventional products and its clinical relevance with a paediatric focus, as well as the health impact of these differences and of contaminants which interfere with metabolism. Other potential differences, particularly regarding the direct/indirect exposure to other contaminants in conventional food, are not addressed in this review. The composition of some organic food may differ from conventional food. Protein content was lower in cereals and eggs. A lower n-6:n-3 polyunsaturated fat (PUFA) ratio was observed in milk, meat and eggs. Long-chain PUFA and vitamin E may be higher in milk, meat and fish, as well as some minerals and antioxidants (phenolic compounds, vitamin C) in fruits, vegetables and starchy food and carotenoids in fruits and vegetables. Epidemiological studies suggest an association between organic diets and lower prevalence of childhood obesity, type 2 diabetes and metabolic syndrome, whereas the protective effect on allergy and cancer is controversial. Some organic food may be of greater nutritional interest for children’s diet than conventional food. Standardised studies comparing food composition and diet in children are needed. Considering the lower toxicologic risk and the sustainability of organic food, the Committee on Nutrition encourages the use of organic food, provided that such food is affordable, alongside specific baby food which is subject to strict specific European Union regulations.
Edited by
Alik Ismail-Zadeh, Karlsruhe Institute of Technology, Germany,Fabio Castelli, Università degli Studi, Florence,Dylan Jones, University of Toronto,Sabrina Sanchez, Max Planck Institute for Solar System Research, Germany
Abstract: This chapter provides a broad introduction to Bayesian data assimilation that will be useful to practitioners in interpreting algorithms and results, and for theoretical studies developing novel schemes with an understanding of the rich history of geophysical data assimilation and its current directions. The simple case of data assimilation in a ‘perfect’ model is primarily discussed for pedagogical purposes. Some mathematical results are derived at a high level in order to illustrate key ideas about different estimators. However, the focus of this chapter is on the intuition behind these methods, where more formal and detailed treatments of the data assimilation problem can be found in the various references. In surveying a variety of widely used data assimilation schemes, the key message of this chapter is how the Bayesian analysis provides a consistent framework for the estimation problem and how this allows one to formulate its solution in a variety of ways to exploit the operational challenges in the geosciences.
The average wave drag in unsteady motion is studied experimentally with force measurements. Towing hulls of size $L$ at sinusoidal speed, the mean drag is measured for different amplitudes and frequencies of the fluctuating velocity, as well as different Froude numbers $\mathcal {F}_0$ associated with the mean velocity $V_0$ ($\mathcal {F}_0 = V_0/\sqrt {gL}$). The wave drag is reported to be either increased or decreased by velocity fluctuations depending on $\mathcal {F}_0$. For small fluctuation amplitudes, this drag change is proportional to the square of the amplitude. The effect is maximized for a resonance frequency identified as the Wehausen frequency, which scales as $\sqrt {g/L}$ times the inverse of the Froude number. All these results are rationalized by developing an extension to Havelock's theory.
The evolution of nomadic collectors' fertility and mortality before the agriculture invention in independent centers 10,000 years ago is still debated. Skeletal samples are the only way to observe prehistoric demographic patterns directly. Each assemblage is critical for direct investigation since pre-farming groups exhibit high residential mobility. Cabeçuda is a funerary mound (sambaqui) in Santa Catarina State, Brazil. Its occupation (4,180BP-1,800BP) corresponds to its expansion peak and decline with horticulturalists' arrival. A cementochronology analysis of 93 skeletons suggests a high frequency of young adults and a lack of adults past 60, which departs from contemporary collector models but is common in catastrophic samples or migratory events. The metabolic load model predicts that a group of semi-nomadic fisher-gatherers should display transitional fertility between sedentary farmers and nomadic collectors. This is the case for Cabeçuda with a 15P5 ratio below and a TFR within all contemporary pre-farming groups. However, within a quasi-stable hypothesis, several variables can produce the same output, and we lack the data to evaluate the death structure.
Electro- and diffusio-phoresis of particles correspond respectively to the transport of particles under electric field and solute concentration gradients. Such interfacial transport phenomena take their origin in a diffuse layer close to the particle surface, and the motion of the particle is force free. In the case of electrophoresis, it is further expected that the stress acting on the moving particle vanishes locally as a consequence of local electroneutrality. But the argument does not apply to diffusiophoresis, which takes its origin in solute concentration gradients. In this paper we investigate further the local and global force balance on a particle undergoing diffusiophoresis. We calculate the local tension applied on the particle surface and show that, counter-intuitively, the local force on the particle does not vanish for diffusiophoresis, in spite of the global force being zero, as expected. Incidentally, our description allows us to clarify the osmotic balance in diffusiophoresis, which has been a source of debate in recent years. We explore various cases, including hard and soft interactions, as well as porous particles, and provide analytic predictions for the local force balance in these various systems. The existence of local stresses may induce deformation of soft particles undergoing diffusiophoresis, hence suggesting applications in terms of particle separation based on capillary diffusiophoresis.
To update the data on food consumption and practices in children under 3 years of age in metropolitan France.
Design
The Nutri-Bébé 2013 cross-sectional study selected a random sample, according to the quota sampling method. After giving their informed consent, parents had to record the food consumption during three non-consecutive days framed by two face-to-face interviews, using for quantitative information different portion size measurement aids.
Results
One thousand one hundred and eighty-four children were enrolled. Mothers’ mean age was 30·8 (sd 5·4) years; 38 % were primiparous; 89 % lived with a partner; 60 % had an occupation. Of the infants younger than 4 months, 31 % were breast-fed. One thousand and thirty-five children consumed infant formula followed by growing-up milk in 63 % of them; solid foods were introduced at a mean age of 5·4 (sd 2·13) months. From 8 months onwards, 25 % of children consumed the same foods as their parents on a more or less regular basis; 29 % ate in front of a screen, with a daily average screen time of 43·0 (sd 40·4) min.
Conclusions
This robust survey highlights the low prevalence and duration of breast-feeding in France and shows a modest improvement since the previous survey of 2005 in the observance of recommendations concerning other feeding practices. The frequent consumption of adult foods and the screen time are of concern.
In this paper, we analyse the dispersion of a dye by a Landau–Squire plume, generated by a jet flow emerging from a nanocapillary into a reservoir. We demonstrate analytically that the dye concentration profile exhibits a long-range profile decaying as the inverse of the distance to the origin, whereas the plume shape is only a function of a Péclet number defined in terms of the flow characteristics inside the nanocapillary. These predictions are successfully compared with experiments on fluorescent dye dispersion from nanocapillaries under pressure-driven flow. The plume shape allows extraction of the nanojet force characterizing the Landau–Squire velocity profile for a given pressure drop, with results in full agreement with direct velocimetry measurements and finite-element calculations. The peculiarities of the Landau–Squire plume make it a sensitive probe of the flow properties inside the seeding nanocapillary.
Carbon materials exist in a large number of allotropic forms and exhibit a wide range of physical and chemical properties. From the perspective of fluidics, particularly within the confines of the nanoscale afforded by one-dimensional carbon nanotubes (CNTs) and two-dimensional graphene structures, many unique properties have been discovered. However, other questions, such as the link between electronic states and hydrodynamics and accurate model predictions of transport, remain unanswered. Theoretical studies, experiments in large-scale ensembles of CNTs and stacked graphene sheets, and precise measurements at the single-pore and single-molecule level have helped in our understanding. These activities have led to explosive growth in the field, now known as carbon nanofluidics. The ability to produce membranes and devices from fluid phases of graphene oxide, which retain these special properties in molecular-scale flow channels, promises realization of applications in the near term.
The study of subglacial movements taking place in regions of cavitation beneath the Glacier d’Argentière, has demonstrated the necessity for using several cavitometers. The very unusual conditions in which such apparatus is installed to measure simultaneously the velocity and the position of the ice vault have led us to design and produce a prototype of a portable cavitometer which records the data on magnetic tape (cassettes).
The works undertaken on the Glacier d’Argentière in order to divert the subglacial stream, have allowed access to several natural cavities which correspond to places where the glacier loses contact with its rock bed. These cavities show a certain number of original phenomena both on the rock bed and also on the ice arch. Studies of the basal ice layer reveal peculiar characteristics which distinguish it from the rest of the ice mass: lamination, interstratification of ice containing sand with pure ice, crystallographic composition, and specific chemical composition.
The sliding speeds of the glacier are variable, and an increase in the friction below these cavitations is at the origin of a form of regressive glacial cavitation. The subglacial cavities are grouped together in a network transverse to the direction of glacier flow; they are interconnected by channels which are more or less open which allow proper thermal exchanges to be established and favour sliding.
As a benefit of modularization of complex systems, original equipment manufacturers (OEMs) can choose suppliers in a less constricted way when faced with new or evolving requirements. However, new suppliers usually add uncertainties to the system development. Because suppliers are tightly integrated into the design process in modular design and therefore greatly influence the outcome of the OEM's products, the uncertainty along with requirements satisfaction of the suppliers and their modules should be controlled starting from potential supplier identification. In addition, to better satisfy new requirements, the potential supplier identification should be combined with architecture generation to enable the new technology integration. In this paper, we propose the Architecture & Supplier Identification Tool, which generates all possible architectures and corresponding suppliers based on new requirements through matrix mapping and propagation. Using the Architecture & Supplier Identification Tool, the overall uncertainty and requirements satisfaction of generated architectures can be estimated and controlled. The proposed method aims at providing decision support for early design of complex systems, thereby helping OEMs have an integrated view of suppliers and system architectures in requirements satisfaction and overall uncertainty.
The diagnosis of cows' milk protein allergy (CMPA) requires first the suspicion of diagnosis based on symptoms described in the medical history, and, second, the elimination of cows' milk proteins (CMP) from the infant's diet. Without such rigorous analysis, the elimination of CMP is unjustified, and sometimes harmful. The elimination diet should be strictly followed, at least until 9–12 months of age. If the child is not breast fed or the mother cannot or no longer wishes to breast feed, the first choice is an extensively hydrolysed formula (eHF) of CMP, the efficacy of which has been demonstrated by scientifically sound studies. If it is not tolerated, an amino acid-based formula is warranted. A rice protein-based eHF can be an alternative to a CMP-based eHF. Soya protein-based infant formulae are also a suitable alternative for infants >6 months, after establishing tolerance to soya protein by clinical challenge. CMPA usually resolves during the first 2–3 years. However, the age of recovery varies depending on the child and the type of CMPA, especially whether it is IgE-mediated or not, with the former being more persistent. Once the child reaches the age of 9–12 months, an oral food challenge is carried out in the hospital ward to assess the development of tolerance and, if possible, to allow for the continued reintroduction of CMP at home. Some children with CMPA will tolerate only a limited daily amount of CMP. The current therapeutic options are designed to accelerate the acquisition of tolerance thereof, which seems to be facilitated by repeated exposure to CMP.
This study deals with a non-exhaustive overview of location systems operating in the 60 GHz frequency band. Both impulse and frequency hopping topologies are considered and the performances of the two realized systems are presented. For each system, a specific signal processing has been implemented to prevent the degradation of the location error from the impact of the multipath propagation.
Recently collected strains from Malay peninsula, Taïwan and Japan proved to be similar to previously studied Japanese strains kept for long time under laboratory conditions. It is therefore possible to speak of a Far East race, characterized by slow growth, very high fresh weight and small ovariole number. High heterogeneity between laboratory strains founded from wild caught flies seems also typical. Among the three traits studied, a positive genetic correlation was observed only between duration of development and adult weight. No correlations were found between biometrical traits and the latitude of strain origin. The problem of the origin of the Far East race is discussed.
Five biometrical traits (thorax length, wing length and width, sternopleural and abdominal chaetae numbers) were measured on 13 equatorial African strains and 30 French strains. In all cases highly significant differences were observed between the two geographic groups. These results are added to previously known variations concerning adult weight and ovariole number. In each place, the genetic particularities of the wild populations seem to be maintained by the selective pressure from environmental conditions, resulting in a homeostatic focusing of the best fitted average genotype. Analysis within each group showed that variations between strains were in most cases poorly or not correlated, so that partial or total genetic independence between the various traits measured seems likely.
Maize agriculture was practiced in the U.S. Southwest slightly before 2000 B.C., but had a negligible impact on population growth rates until the development or introduction of more productive landraces; the ability to successfully cultivate maize under a greater variety of conditions, with dry farming especially important; the addition of beans, squash, and eventually turkey to the diet; increased sedentism; and what we infer to be the remapping of exchange networks and the development of efficient exchange strategies in first-millenium-A.D. villages. Our estimates of birthrates and growth rates are derived from the proportions of immature individuals among human remains. These proportions are somewhat affected by warfare in our region, and perhaps also by climate. Nevertheless, there is a strong identifiable Neolithic Demographic Transition signal in the U.S. Southwest in about the mid-first-millennium A.D. in most subregions, visible a few hundred years after the introduction of well-fired ceramic containers, and more or less contemporaneous with the first appearance of villages. Independent genetic data derived from the mitochondrial genomes of present-day indigenous populations of the Southwest are also consistent with the hypothesis that a major demographic expansion occurred 1,500-2000 years ago in the Southwest.
We present the realization of hybrid silicon core/silicon nitride shell nanodots by Low Pressure Chemical Vapor Deposition (LPCVD) and their application as floating gate in Non Volatile Memory (NVM) devices. The LPCVD process includes three steps: nucleation using SiH4, selective growth of the silicon nuclei using SiH2Cl2 and finally selective growth of silicon nitride using a mixture of SiH2Cl2 and NH3 around the silicon dot. The two first steps have already been described in literature. We will therefore focus on the selective growth of a nitride layer on silicon dots. Morphological characterization using Scanning Electron Microscopy (SEM) allows control over dots size – 5 to 10nm – and density – up to 1E12/cm2. High Resolution Transmission Electron Microscopy (HRTEM) shows a crystalline silicon core and an outer shell of amorphous silicon nitride. Energy Filtered TEM pictures confirm that the nitride layer is deposited only around the silicon dots and not on the oxide. Oxidation resistance of the silicon nitride shell is also investigated. A 2nm thick silicon nitride layer is an efficient barrier to an oxidation at 800°C in dry oxygen for 5 minutes. We thus have a very thin high quality stoechiometric nitride layer. Such a high quality nitride film can only be achieved using in-situ deposition i.e. on an oxide-free silicon surface. Finally, hybrid Si/SiN nanodots are integrated in a single memory cell with high-K interpoly dielectric. Electrical results show large threshold voltage shift of 6V. The use of silicon nitride shells on the silicon dots has therefore two main advantages: it provides both oxidation resistance and charge storage enhancement.
We study the collapse of a transient cavity of air in water created by the impact of a solid body. Experimentally, we characterize the dynamics of the cavity from its creation (t = 0) until it collapses (t = τ) in the limit where inertia dominates viscous and capillary effects. Theoretically, we find in this regime an approximate analytical solution which describes the time evolution of the shape of the cavity. This theoretical solution predicts the existence of two different types of cavities that we also observe experimentally.
We first report a quantitative experimental study of the collision of a spinning disk with water, from a single to many skips. We then focus on the high spin limit and propose a simple model which enables us to discuss both the physical origin of the bounces and the source of the dissipation which fixes the number of skips.