Showing papers by "Conservatoire national des arts et métiers published in 2006"

The relationship between health care expenditure and health outcomes. Evidence and caveats for a causal link.

Abstract: The relationship between health care expenditure and health outcomes is of interest to policy makers in the light of steady increases in health care spending for most industrialised countries. However, establishing causal relationships is complex because, firstly, health care expenditure is only one of many quantitative and qualitative factors that contribute to health outcomes, and, secondly, measurement of health status is an imperfect process. This study reviews key findings and methodological approaches in this field and reports the results of our own empirical study of countries of the European Union. Our analysis examines life expectancy and infant mortality as the ‘output’ of the health care system, and various life-style, environmental and occupational factors as ‘inputs’. Econometric analyses using a fixed effects model are conducted on a panel data set for the former 15 members of the European Union over the period 1980–1995. The findings show that increases in health care expenditure are significantly associated with large improvements in infant mortality but only marginally in relation to life expectancy. The findings are generally consistent with those of several previous studies. Caveats and improvements for future research are presented.

Norms-Based Intellectual Property Systems: The Case of French Chefs

Abstract: In this paper we propose that "norms-based" intellectual property systems exist today, and are an important complement to or substitute for law-based intellectual property systems. Norms-based IP systems, as we define them, operate entirely upon the basis of implicit social norms that are held in common by members of a given community. Within that community, they offer functionality similar to contemporary law-based IP systems with respect to both the nature of rights protected and the effectiveness of protection provided. We document the existence of a norms-based IP system among a sample of accomplished French chefs. These chefs consider recipes they develop to be a very valuable form of intellectual property. At the same time, recipes are not a form of innovation that is effectively covered by law-based intellectual property systems. Via grounded research, we identify three strong implicit social norms related to the protection of recipe IP. Via quantitative research, we find that accomplished chefs enforce these norms, and apply them in ways that enhance their private economic returns from their recipe-related IP. In our discussion, we compare the attributes of norms-based and law-based IP systems, arguing that each has different advantages and drawbacks. We also point out that the existence of norms-based IP systems means that many "information commons" may prove to be criss-crossed by norms-based fences, with community access controlled by community IP owners.

Determination of the fine structure constant based on bloch oscillations of ultracold atoms in a vertical optical lattice

Abstract: We report an accurate measurement of the recoil velocity of Rb atoms based on Bloch oscillations in a vertical accelerated optical lattice. We transfer about 900 recoil momenta with an efficiency of 99.97 % per recoil. A set of 72 measurements of the recoil velocity, each one with a relative uncertainty of about 33 ppb in 20 min integration time, leads to a determination of the fine structure constant alpha with a statistical relative uncertainty of 4.4 ppb. The detailed analysis of the different systematic errors yields to a relative uncertainty of 6.7 ppb. The deduced value of 1/alpha is 137.03599878(91).

Wheat lipoxygenase activity induces greater loss of carotenoids than vitamin E during breadmaking.

Abstract: The current study was undertaken to provide solutions to optimize the unsaponifiable antioxidants content of bread. We report a complete description of changes in wheat carotenoids and vitamin E content from grain to bread and highlight the most important processing steps affecting their level in wheat bread. Major carotenoids losses occurred during kneading. A close correlation (r(2) = 0.97; P = 0.05) was found between carotenoid pigment losses and lipoxygenase (LOX) activity, both parameters depending on wheat genotype. The use of wheat species exhibiting high carotenoid contents and low LOX activity was shown to preserve significant carotenoid level in the bread. No relation was found between vitamin E losses during doughmaking and LOX activity. In addition, moderate kneading resulted in higher vitamin E retention in comparison with carotenoids (12% and 66% losses, respectively). It is concluded that carotenoids are more susceptible to oxidation by endogenous lipoxygenase than vitamin E during breadmaking. This study showed that bread nutritional quality, in terms of antioxidant content, could be improved by selecting suitable cereal genotypes, if this potential is preserved by milling and baking processes.

Review article: the role of bacteria in onset and perpetuation of inflammatory bowel disease

Abstract: We review the evidence that strongly suggests a role of the intestinal microbiota in the onset and perpetuation of inflammatory bowel disease (IBD). Experimental studies consisted of suppressing micro-organisms from the microbiota (using germ-free or gnotoxenic animals or antibiotics), introducing new micro-organisms or microbial components (e.g. probiotics, CpG-DNA) or selectively increasing some endogenous bacteria (e.g. using prebiotics). Intervention studies were performed in patients or animal models of spontaneous or chemically-induced colitis. Information was also obtained from observational studies that described the composition of the faecal and mucosal microbiota at various stages of the disease process and in controls. Many have used culture-independent techniques that identify bacteria based on the nucleic acid sequence of ribosomal RNA molecules. Microbiota in patients with IBD seem to be characterized by high concentrations of bacteria in contact with the mucosa, instability, the presence of high numbers of unusual bacteria and sometimes a reduction in the biodiversity. Studies searching for a generalized or localized dysbiosis in IBD are discussed, as well as those trying to identify bacterial molecules and receptors, which may be implicated in triggering the inflammatory process.

A UML-based data warehouse design method

Abstract: Data warehouses are a major component of data-driven decision support systems (DSS). They rely on multidimensional models. The latter provide decision makers with a business-oriented view to data, thereby easing data navigation and analysis via On-Line Analytical Processing (OLAP) tools. They also determine how the data are stored in the data warehouse for subsequent use, not only by OLAP tools, but also by other decision support tools. Data warehouse design is a complex task, which requires a systematic method. Few such methods have been proposed to date. This paper presents a UML-based data warehouse design method that spans the three design phases (conceptual, logical and physical). Our method comprises a set of metamodels used at each phase, as well as a set of transformations that can be semi-automated. Following our object orientation, we represent all the metamodels using UML, and illustrate the formal specification of the transformations based on OMG's Object Constraint Language (OCL). Throughout the paper, we illustrate the application of our method to a case study.

Ternary chalcogenides LiBC2 (B = In, Ga; C = S, Se, Te) for mid-IR nonlinear optics

Abstract: We review on the growth improvement and optical characterization of a new family of ternary lithium-based chalcogenide crystals of generic formula LiB III C 2 VI (B = In, Ga; C = S, Se, Te) which displays improved thermo-mechanical properties for mid-IR nonlinear optical applications. Some of these compounds are now produced in sufficiently large size, single-domain quality to allow their implementation in optical parametric oscillators.

Acoustic thermometry: new results from 273 K to 77 K and progress towards 4 K

Abstract: We used a quasi-spherical cavity as an acoustic and microwave resonator to measure the thermodynamic temperatures, T, of the triple points of equilibrium hydrogen, neon, argon and mercury and to measure the difference T − T90, in the range 7 K to 273 K. (T90 is the temperature on the International Temperature Scale of 1990 (ITS-90).) In the range 7 K to 24.5 K, our preliminary values of T − T90 agree with recent results from dielectric-constant gas thermometry and achieve uncertainties that are comparable to or smaller than those achievable using the interpolating constant volume gas thermometer as currently defined on the ITS-90. In the range 90 K to 273 K, the present results for T − T90 obtained using a helium-filled, copper-walled, quasi-spherical cavity agree with earlier results obtained using argon-filled, steel-walled or aluminium-walled, spherical cavities. The agreement confirms our understanding of both acoustic and microwave cavity resonators and demonstrates that resonators function as primary thermometers spanning wide temperature ranges. The mutually consistent acoustic thermometry data from several laboratories imply that the values of (T − T90)/T90 are 5 times larger than the uncertainty of T/T90 near 150 K and near 400 K. They also imply that the derivative dT/dT90 is too large by approximately 10−4 near 273.16 K and that dT/dT90 has a discontinuity of 4 × 10−5 at 273.16 K.

Coffee Antioxidant Properties: Effects of Milk Addition and Processing Conditions

Abstract: In the human diet, coffee is the major source of caffeoyl-quinic acids known as powerful antioxidants. The aim of this study was to assess the effect of usual coffee consumption, such as the addition of milk, and of processing conditions, such as spray-drying, on beverage antioxidant power and potential polyphenol bioavailability impairments. When 25% milk was added to coffee, up to 40% of coffee chlorogenic acid were found to be bound to dairy proteins, using an ultrafiltration technique. However, neither milk addition nor spray-drying had a significant effect on beverage antioxidant power, evaluated using 2,2-diphenyl-1-pycrylhydrazyl (DPPH), 2-2′-azobis (2-amidinopropane) dihydrochloride (AAPH), and total antioxidant capacity (TAC) tests. Moreover, these interactions tended to decrease during in vitro gastric and intestinal digestion, thus suggesting that interactions between chlorogenic acid and milk proteins in coffee and milk beverage may not have any significant effect on coffee antioxidant power before and after consumption.

Factors influencing blood concentration of retinol, alpha-tocopherol, vitamin C, and beta-carotene in the French participants of the SU.VI.MAX trial.

Abstract: Factors influencing blood concentration of retinol, α -tocopherol, vitamin C, and β -carotene in the French participants of the SUVIMAX trial

Carbon dioxide capture by indirect thermal swing adsorption using 13X zeolite

Abstract: The aim of this article is to investigate the performances of an indirect temperature swing adsorption process for CO2 removal from nitrogen using 13X zeolite. Breakthrough experiment, with a 10% CO2–N2 mixture, were performed showing that thanks to the cooling, the adsorbent capacity is preserved and close to that of an isothermal adsorption. For the desorption step, CO2 at a concentration of nearly 100% is recovered thanks to the indirect heating and the non-use of purge gas. During the cycle experiments, we obtained 7.9 MJ/kg for the specific heat consumption. This value is slightly higher than amine absorption ones, which is the reference process for CO2 capture. However, it has to be taken into account that there is a good potential of energy saving because our process configuration (adsorbent choice, number of beds, step duration, etc.) has not been optimized yet. Moreover, in scaled-up process, the heat losses are of less importance, which will decrease the specific heat consumption. This is confirmed by a first estimation, which gives a value of 5.9 MJ/kg. © 2006 American Institute of Chemical Engineers Environ Prog, 25: 327–333, 2006

Chlorogenic acid is poorly absorbed, independently of the food matrix: A Caco-2 cells and rat chronic absorption study

Abstract: According to epidemiologic studies, dietary phenolic antioxidants, such as chlorogenic acid (CQA), could prevent coronary heart diseases and some cancers. Coffee is the main source of CQA in the human diet. The aim of this study was to assess the effect of usual coffee consumption conditions, such as the addition of milk, on CQA bioavailability. Interactions between CQA and milk proteins were shown, using an ultrafiltration technique. These interactions proved to be slightly disrupted during an in vitro digestion process. CQA absorption and bioavailability were then studied in vitro using a Caco-2 cell model coupled with an in vitro digestion process, and in vivo, in a chronic supplementation study in which rats were fed daily coffee or coffee and milk for 3 weeks. Both experiments showed that CQA absorption under its native form is weak, but unmodified by the addition of milk proteins, and slightly reduced by the addition of Maillard reaction products. These data show that there are some interactions between coffee phenolics and milk proteins, but these have no significant effect on CQA bioavailability from coffee in the rat. CQA is poorly absorbed under its native form in the body, when ingested in a realistic food matrix.

Robust nonlinear control associating robust feedback linearization and H/sub /spl infin// control

Abstract: In this note, a robust nonlinear controller for a nonlinear system subject to model uncertainties is proposed Such a controller associates a "robust feedback linearization" with a robust linear H/sub /spl infin// controller The robust feedback linearization exactly transforms the nonlinear system into a linear system equal to the linear approximation of the original nonlinear system around a nominal operating point The robustness of the resulting overall nonlinear controller is proved by theoretical arguments and illustrated through an application example, the control of a magnetic bearing system

Evaluation of Non-Medical Costs Associated with Visual Impairment in Four European Countries

Abstract: Introduction Visual impairment is a severe disability that puts a heavy burden on individuals, families and society. In developed countries, the two major diseases leading to irreversible visual impairment are glaucoma and age-related macular degeneration. Their prevalence will increase dramatically with population aging. The economic consequences of visual impairment are considerable, but have rarely been documented, apart from some ‘top-down’ estimates based on national statistics. We estimated the non-medical costs related to visual impairment in four European countries: France, Italy, Germany and the UK.

Cytokine-induced alteration of the epithelial barrier to food antigens in disease

Abstract: The alteration of the intestinal epithelial barrier is often a consequence of various intestinal diseases but may also be the starting point of these diseases. Undigested food antigens are transported across the intestinal epithelium by a transcytotic mechanism, including a processing within the enterocytes, and leading to the passage of intact proteins, peptides, and amino acids to the underlying mucosa. Inflammation and infection lead to the upregulation of the transport and processing of food proteins; for example, IFN gamma increases the rate of transcytosis and alters, like TNF alpha, the tight junction permeability. Infection of gastric digestive epithelia with Helicobacter pylori also increases the antigenic load transmitted to the underlying immune system by inhibiting the enterocytic lysosomal degradation of proteins. In allergic diseases, such as cow's milk allergy, TNF alpha may be involved in the intestinal dysfunction and the associated enteropathy.

Complementary feeding adequacy in relation to nutritional status among early weaned breastfed children who are born to HIV-infected mothers: ANRS 1201/1202 Ditrame Plus, Abidjan, Cote d'Ivoire

Abstract: OBJECTIVE: In high HIV prevalence resource-constrained settings, exclusive breastfeeding with early cessation is one of the conceivable interventions aimed at the prevention of HIV through breast milk. Nevertheless, this intervention has potential adverse effects, such as the inappropriateness of complementary feeding to take over breast milk. The purpose of our study first was to describe the nature and the ages of introduction of complementary feeding among early weaned breastfed infants up to their first birthday and second was to assess the nutritional adequacy of these complementary foods by creating a child feeding index and to investigate its association with child nutritional status. METHODS: A prospective cohort study in Abidjan, C?d'Ivoire, was conducted in HIV-infected pregnant women who were willing to breastfeed and had received a perinatal antiretroviral prophylaxis. They were requested to practice exclusive breastfeeding and initiate early cessation of breastfeeding from the fourth month to reduce breast milk HIV transmission. Nature and ages of introductory complementary feeding were described in infants up to their first birthday by longitudinal compilation of 24-hour and 7-day recall histories. These recalls were done weekly until 6 weeks of age, monthly until 9 months of age, and then quarterly. We created an index to synthesize the nutritional adequacy of infant feeding practices (in terms of quality of the source of milk, dietary diversity, food, and meal frequencies) ranging from 0 to 12. The association of this feeding index with growth outcomes in children was investigated. RESULTS: Among the 262 breastfed children included, complete cessation of breastfeeding occurred in 77% by their first birthday, with a median duration of 4 months. Most of the complementary foods were introduced within the seventh month of life, except for infant food and infant formula that were introduced at age 4 months. The feeding index was relatively low (5 of 12) at age 6 months, mainly as a result of insufficient dietary diversity, but was improved in the next 6 months (8.5 of 12 at 12 months of age). Inadequate complementary feeding at age 6 months was associated with impaired growth during the next 12 months, with a 37% increased probability of stunting. CONCLUSION: Adequate feeding practices around the weaning period are crucial to achieving optimal child growth. HIV-infected women should turn to early cessation of breastfeeding only when they are counseled properly to provide adequate complementary feeding to take over breast milk. Our child feeding index could contribute to the assessment of the nutritional adequacy of complementary feeding around the weaning period and therefore help to detect children who are at risk for malnutrition.

Polypyrrole-Fe2O3 nanohybrid materials for electrochemical storage

Abstract: We report on the synthesis and electrochemical characterization of nanohybrid polypyrrole (PPy) (PPy/Fe2O3) materials for electrochemical storage applications. We have shown that the incorporation of nanoparticles inside the PPy notably increases the charge storage capability in comparison to the “pure” conducting polymer. Incorporation of large anions, i.e., paratoluenesulfonate, allows a further improvement in the capacity. These charge storage modifications have been attributed to the morphology of the composite in which the particle sizes and the specific surface area are modified with the incorporation of nanoparticles. High capacity and stability have been obtained in PC/NEt4BF4 (at 20 mV/s), i.e., 47 mAh/g, with only a 3% charge loss after one thousand cyles. The kinetics of charge–discharge is also improved by the hybrid nanocomposite morphology modifications, which increase the rate of insertion–expulsion of counter anions in the bulk of the film. A room temperature ionic liquid such as imidazolium trifluoromethanesulfonimide seems to be a promising electrolyte because it further increases the capacity up to 53 mAh/g with a high stability during charge–discharge processes.

Malaria treatment in remote areas of Mali: use of modern and traditional medicines, patient outcome

Abstract: Use of official health services often remains low despite great efforts to improve quality of care. Are informal treatments responsible for keeping a number of patients away from standard care, and if so, why? Through a questionnaire survey with proportional cluster samples, we studied the case histories of 952 children in Bandiagara and Sikasso areas of Mali. Most children with reported uncomplicated malaria were first treated at home (87%) with modern medicines alone (40%), a mixture of modern and traditional treatments (33%), or traditional treatment alone (27%). For severe episodes (224 cases), a traditional treatment alone was used in 50% of the cases. Clinical recovery after uncomplicated malaria was above 98% with any type of treatment. For presumed severe malaria, the global mortality rate was 17%; it was not correlated with the type of treatment used (traditional or modern, at home or elsewhere). In the study areas, informal treatments divert a high proportion of patients away from official health services. Patients' experience that outcome after standard therapeutic itineraries is not better than after alternative care may help to explain low use of official health services. We need to study whether some traditional treatments available in remote villages should be considered real, recommendable first aid.