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Precise analysis of complex gas mixtures is an urgent task today, since its accuracy and quality is important not only for human health, but also for the ecology of population centers or the planet as a whole. Traditional methods of gas environment analysis are imperfect, and those that have the necessary sensitivity and selectivity do not yield results in a particularly short time. Nowadays, the Fabry- Pérot interferometry is used for research in a significant number of industrial and scientific areas. The analysis of the works presented in this paper confirms the relevance of research in the field of multibeam interferometry and the prospects of developing modifications of the Fabry- Pérot interferometer. The article is devoted to classical optical correlation methods for the analysis of gas mixtures with a quasi-periodic structure of the spectrum. A modification of the analyzer was developed and it was shown that the use of the modified Fabry- Pérot interferometer as a correlation mask ensures the express realization of the selectivity of the measurement components. An experimental study was conducted to test the possibility of scanning the SO2 absorption spectrum in the 220 nm region. Laboratory tests of the described layout of the SO2 analyzer demonstrated its high metrological parameters. The main reported error was 1% on the 0 -10000 ppm scale and 10% on the 0 -1000 ppm scale. The length of the cuvette was 170 mm, the warm-up time of the model was 30 minutes, the minimum measured concentration was 25 ppm. We can state that the correlation masks based on the IFP can be widely used for the analysis of gas components with a quasi-periodic structure of the spectrum. Compared to other devices of a similar type, they have a much higher luminous intensity: U = ΩA, where Ω is the solid angle; A is the light diameter of the IFP with the same resolution. This is crucial for remote instruments [V. R. Kozubovskii, Yu. Yu. Bilak, Ukr. J. Phys. 66, 664 (2021)]. In addition, their small weight and dimensions allow one to create portable devices based on them. However, since the IFP is a multi-beam interferometer, the procedure for optimizing its parameters is rather complicated, although technical methods for solving this problem exist [V. R. Kozubovskii, V. L. Goldovskii, O. D. Kraysler, AS 1182345 USSR, MKI G01N 21/61]. The conducted analysis and research open up new opportunities for the optimization of interferometric devices and interferometric methods of gas analysis. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Geological Hazard & Control is the property of China Institute of Geological Environmental Monitoring (CIGEM) Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The beaches of Oran are among the busiest in Algeria. However these beaches are exposed to multiple dangers in particular to pollution which poses serious problems and which can also hinder any proper use of the sea. This paper is an assessment of the physico-chemical and bacteriological quality of some beaches where swimming is allowed along the Oranese coast in Algeria, specifically the Kristel Beach and the beach of Les Andalouses seaside resort. Fecal streptococci are normal hosts of the intestine of humans and warm-blooded animals. Research concerning them associated with that of fecal coliforms is a good indication of fecal contamination. Their presence indicates long term contamination of fecal origin while the presence of fecal coliforms indicates a contamination of recent fecal origin. This is why it may become necessary to proceed to the confirmation stage to detect the presence of E. Coli, which is in fact the real indicator sought in this context, through the necessary use of E. Coli specific culture media. The results obtained show a slight difference between the two sites as the beach of Les Andalouses is a bit more polluted compared to that of Kristel. Still, both beaches remain of good quality with regard to national and international standards. [ABSTRACT FROM AUTHOR]

Objective: The objective of the study was to assess the effect of A,D3,E (I/M) and oregano oil extract 15% on some clinicopathological parameters during lamb bacterial enteritis treatment. Materials and Methods: Sixty Barki lambs, 20 apparently healthy (control group) and, 40 suffered from bacterial enteritis [enteric group (EG)], were subdivided into four treated groups (TGs): antibiotic group (AG), antibiotic + A,D3,E group (A + A,D3,E), antibiotic + oregano oil (AOG), and oregano group (OG). Fecal swabs were collected from EG then aseptically cultured, isolated, phenotypically identified, genotypically confirmed, and sequenced by PCR 16srRNA. Paper disk diffusion test was used for estimation of oregano oil extract 15% antibacterial activity. After blood sample aspiration from all animals, they were clinicopathologically and statistically analyzed. Results: Escherichia coli, followed by Salmonella species and then Klebsiella species, was the main causative agents of lamb diarrhea and were susceptible to oregano oil extract 15%. A + A,D3,E and AOG showed significant (p < 0.05) enhancement of some clinicopathological parameters more than AG or OG. Matrix metalloproteinases (MMP-2 and MMP-9) and total antioxidant capacity (TAC), yielded area under the curve, sensitivity, negative predictive value as 1, 100% and 100% respectively, were determined in both EG and TGs. Conclusion: Oregano oil extract 15% has good antibacterial properties against enteric bacteria in vitro and in vivo. The combination between antibiotic and antioxidant vitamins or oregano plant extract of 15% has a good impact on some clinicopathological alterations in lamb bacterial enteri- tis treatment. TAC, MMP-9, and MMP-2 may be good markers for the disease and its treatment follow-up. [ABSTRACT FROM AUTHOR]

Background Cardiovascular toxicity as a consequence of nicotine from conventional tobacco cigarette smoking is well documented. However, little is known about the cardiovascular consequences of nicotine e-vaping. We review the literature and report a case series of three cases of major adverse cardiovascular clinical effects post nicotine e-vaping. Case summary Three patients with known peripheral arterial disease who switched from heavy cigarette smoking consumption to a high-intensity dose of nicotine e-vaping all developed further arterial complications within 6–30 months. Discussion With the recent epidemic of e-vaping in young individuals and the national outbreak of e-vaping use-associated lung injury (EVALI), the dangers of e-vaping are now coming to light. The pulmonary effects are now well described, and this paper highlights three new cases of cardiovascular toxicity associated with e-vaping. The potential role of nicotine e-vaping and the risk of coronavirus disease-2019 (COVID-19) will also be discussed. [ABSTRACT FROM AUTHOR]

Copyright of Veritas is the property of EDIPUCRS - Editora Universitaria da PUCRS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To analyze monetary policy implementation in a negative rate environment, we add the option to exchange central bank reserves for cash to the standard workhorse model of monetary policy implementation (Poole 1968). Importantly, we show that monetary policy can be constrained when the target overnight rate is below the yield on cash. At this point, the overnight rate equals the yield on cash instead of the target rate. Modifications to the implementation framework, such as a reserve requirement that varies with cash withdrawals, can help restore the implementation of monetary policy such that the overnight rate equals the target rate. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Faculty of Education, Beni Suef University is the property of Beni Suef University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report an outbreak of confirmed Mycoplasma pneumoniae community-acquired pneumonia (CAP) in Nord Franche-Comté Hospital, France, from 14 November 2023 to 31 January 2024. All 13 inpatients (11 adults with a mean age of 45.5 years and 2 children) were diagnosed with positive serology and/or positive reverse transcription polymerase chain reaction (RT-PCR) on respiratory specimens. All patients were immunocompetent and required oxygen support with a mean duration of oxygen support of 6.2 days. Two patients were transferred to the intensive care unit (ICU) but were not mechanically ventilated. Patients were treated with macrolides (n = 12, 92.3%) with recovery in all cases. No significant epidemiological link was reported in these patients. [ABSTRACT FROM AUTHOR]

Copyright of Revista EAN is the property of Universidad EAN and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science: Future of Lithuania / Mokslas: Lietuvos Ateitis is the property of Vilnius Gediminas Technical University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The basic aim of the paper is both to offer - through critical »reading« of the popular music cultural product in Zagreb between the two world wars - a review of the diversified usable characteristics of particular musical products that circulated on the then-market of symbolic assets, as well as to single out - in the context of accessible testimonies and data on the social and cultural status of music and its participants during that period - the possible functional dispositions which that product, specifically anchored in time and place, used to have. Creating a theoretical basis by drawing on various, primarily cultural and critical comprehensions of popular music, as well as from other broader context components of the functioning of culture, the paper offers a »polygonal« approach to the popular music phenomenon against the background of textual reading off of its articulations and meanings through (not necessarily) musicologically mediated media and analytical procedures. From comprehension of the very phenomenon of the popular and the popularity of music in the period under consideration, through the interpretation of popular music's functional nesting in the sociocultural context, the paper offers indications of certain basic implications of that way of studying music. The work also touches upon an attempt at the conceptual encompassing of music, not only as note and sound structures mediated by media, but also as a broader cultural product that is exposed to diverse usages and different aims, purposes and functions; of which the popular-fictional feature is certainly a significant one. [ABSTRACT FROM AUTHOR]

The development of atmospheric lightning is initiated and sustained by the formation in virgin air of ‘streamer corona’ and ‘leader’ discharges, very similar to those observed in laboratory long sparks. Therefore, the experimental and theoretical investigations of these laboratory discharges have become of large interest to improve the physical knowledge of the lightning process and to develop self-consistent models that could be applied to new protection concepts.In the present paper the fundamental processes of the subsequent phases of long air gap discharges are analyzed, from the first corona inception and development to the leader channel formation and propagation. For all these processes simulations models are discussed that have been essentially derived and simplified by the authors, in order to develop sequential time-dependent simulation of the laboratory breakdown, with both positive and negative voltages. The possibility of extending these models to the case of natural lightning is discussed in the companion paper, presented in this same volume. To cite this article: I. Gallimberti et al., C. R. Physique 3 (2002) 1335–1359. [Copyright &y& Elsevier]

3D printed short carbon fiber reinforced thermoplastic (SCFRTP) composites have complex multi-scale morphologies. These morphologies significantly affect the mechanical properties of SCFRTP. However, the existing research on multi-scale structural morphology formation and multi-scale mechanical responses of 3D printed SCFRTP composites is obviously insufficient so far. Herein, full-process multi-scale morphological and mechanical analyses of 3D printed SCFRTP composites are conducted in depth. Initially, the SCFRTP composites with the special engineering plastic polyetheretherketone (PEEK) as matrix and short carbon fiber (SCF) as filler (SCF contents of 1 wt%, 3 wt%, 5 wt%, 7 wt% and 10 wt%) are manufactured by 3D printing based on the principle of fused deposition modeling. The multi-scale structural morphologies of these composites are systematically characterized. Then, theoretical investigations are conducted to describe the flow behavior, crystallization and viscosity changes during 3D printing molding process, as well as the conservation of mass, momentum and energy for SCF/PEEK composites. The fluid-solid interaction numerical model is established to analyze the printing process of SCFRTP composites. Based on this model, the multi-scale morphologies of 3D printed SCFRTP composites are predicted, and the generation mechanism of multi-scale void defects in 3D printed SCFRTP composites is clarified. Subsequently, the multi-scale mechanical analysis of 3D printed SCFRTP composites is performed to predict the mechanical parameters of micro-traces, the performances of meso-layers and the mechanical properties of macro-3D printed SCFRTP specimens. The full-process from generation in manufacturing to evolution under tension of multi-scale void defects is described by the proposed model. The deviation between the experiment result and the numerical prediction which takes multi-scale void defects and fiber probability density distributions into account is much smaller compared with numerical results ignoring the multi-scale structures. Therefore, the full-process multi-scale analysis method proposed in this paper is of great significance to accurately predict the mechanical properties of 3D printed SCFRTP composites. [Display omitted] [ABSTRACT FROM AUTHOR]

Antiviral treatments for early intervention in patients with mild-to-moderate COVID-19 are needed as a complement to vaccination. We sought to estimate the impact on COVID-19 cases, deaths, and direct healthcare costs over 12 months following introduction of a novel, antiviral treatment, RD-X19, a light-based, at-home intervention designed for the treatment of mild-to-moderate COVID-19 infection. A time-dependent, state transition (semi-Markov) cohort model was developed to simulate infection progression in individuals with COVID-19 in 3 US states with varying levels of vaccine uptake (Alabama, North Carolina, and Massachusetts) and at the national level between 1 June 2020 and 31 May 2021. The hypothetical cohort of patients entering the model progressed through subsequent health states after infection. Costs were assigned to each health state. Number of infections/vaccinations per day were incorporated into the model. Simulations were run to estimate outcomes (cases by severity, deaths, and direct healthcare costs) at various levels of adoption of RD-X19 (5%, 10%, 25%) in eligible infected individuals at the state and national levels and across three levels of clinical benefit based on the results from an early feasibility study of RD-X19. The clinical benefit reflects a decline in the duration of symptomatic disease by 1.2, 2.4 (base case), and 3.6 days. In the base case analysis with 10% adoption, simulated infections/deaths/direct healthcare costs were reduced by 10,059/275/$69 million in Alabama, 21,092/545/$135 million in North Carolina, and 16,670/415/$102 million in Massachusetts over 12 months. At the national level, 10% adoption reduced total infections/deaths/direct healthcare costs by 686,722/17,748/$4.41 billion. At-home, antiviral treatment with RD-X19 or other interventions with similar efficacy that decrease both symptomatic days and transmission probabilities can be used in concert with vaccines to reduce COVID-19 cases, deaths, and direct healthcare costs. [ABSTRACT FROM AUTHOR]

The technology of very high performance cooled infrared detectors made with HgCdTe has progressed continuously for ten years and reached today an industrial maturity that allows the production of large size arrays at a more and more reasonable cost. At the same time, new prototypes of more complex sensors have appeared (megapixel arrays, multicolour arrays, high definition long linear arrays, …) that show the strong potentialities of this very high performance technology. This paper presents the technology developed in France and gives the state of the art of products available in industry; it then focuses on some very recent realizations of advanced prototypes made at LETI (dualband arrays, megapixel arrays, …). To cite this article: G. Destefanis, C. R. Physique 4 (2003). [Copyright &y& Elsevier]

Standard GaAs/AlGaAs QWIPs (Quantum Well Infrared Photodetector) are now well established for long wave infrared (LWIR) detection. The main advantage of this technology is the duality with the technology of commercial GaAs devices. The realization of large FPAs (up to 640×480) drawing on the standard III–V technological process has already been demonstrated. The second advantage widely claimed for QWIPs is the so-called band-gap engineering, allowing the custom design of the quantum structure to fulfill the requirements of specific applications such as multispectral detection. QWIP technology has been growing up over the last ten years and now reaches an undeniable level of maturity. As with all quantum detectors, the thermal current, particularly in the LWIR range, limits the operating temperature of QWIPs. It is very crucial to achieve an operating temperature as high as possible and at least above 77 K in order to reduce volume and power consumption and to improve the reliability of the detection module. This thermal current offset has three detrimental effects: noise increase, storage capacitor saturation and high sensitivity of FPAs to fluctuations in operating temperature. For LWIR FPAs, large cryocoolers are required, which means volume and power consumption unsuitable for handheld systems. The understanding of detection mechanisms has led us to design and realize high performance ‘standard’ QWIPs working near 77 K. Furthermore, a new in situ skimmed architecture accommodating this offset has already been demonstrated. In this paper we summarize the contribution of THALES Research & Technology to this progress. We present the current status of QWIPs in France, including the latest performances achieved with both standard and skimmed architectures. We illustrate the potential of our QWIPs through features of Thales Optronique''s products for third thermal imager generation. To cite this article: E. Costard et al., C. R. Physique 4 (2003). [Copyright &y& Elsevier]

In this paper we discuss the problem of computing and analyzing the static equilibrium of a nonrigid water tank. Specifically, we fix the amount of water contained in the tank, modelled as a membrane. In addition, there are rigid obstacles that constrain the deformation. This amounts to a nonconvex variational problem. We derive the optimality system and its interpretation in terms of equilibrium of forces. A second-order sensitivity analysis, allowing to compute derivatives of solutions and a second-order Taylor expansion of the cost function, is performed, in spite of the fact that the cost function is not twice differentiable. We also study the finite elements discretization, introduce a decomposition algorithm for the numerical computation of the solution, and display numerical results. [Copyright &y& Elsevier]

Stephen J. Gould, mitrates and monsters. The interest of analyses based on teratological specimens to understand the mechanisms and rules of ontogenetic development is a central theme in Gould''s literature. This paper deals with monsters through two topics focusing on a group of atypical Palaeozoic echinoderms: mitrate stylophorans. The first topic deals with the phyletic position of stylophorans within deuterostomes. Three rival scenarios have been proposed, based on different interpretations of the stylophoran appendage. One of these scenarios implies that mitrates are « hopeful monsters » (calcichordate theory). An analogy with various hypotheses formulated for the disappearance of dinosaurs shows that the calcichordate model is not a scientific hypothesis, unlike the two other interpretations, which can be tested. The second topic is dedicated to the description of an abnormal specimen of the mitrate Mitrocystites mitra, from the Middle Ordovician of Bohemia. The abnormal plating of its lower surface suggests that the insertion of centrals within the posterior region of the marginal thecal frame is an iterative phenomenon in Mitrocystitida. To cite this article : B. Lefebvre, C. R. Palevol 2 (2003). [Copyright &y& Elsevier]

Gould as a biometrician. Between 1965 and 1973, S.G. Gould published numerous papers on allometry, which established his scientific reputation. This topic allowed him to be aware of the consequences of problems of scale on morphologic evolution. To cite this article: J. Gayon, C. R. Palevol 2 (2003). [Copyright &y& Elsevier]

In this paper, a differentially heated square/cubic cavity is studied by performing three-dimensional direct numerical simulations. The first bifurcation observed at Ra&ap;3.2×107 is due to the 3D vortex structures generated at the end regions of vertical boundary layers near the median plane. The main results of this Note are that the flow returns to a steady state for higher values of the Rayleigh number Ra (7×107 and 108 for example) still exhibiting these 3D vortex structures, and that multiple steady flows which differ by their symmetry properties, are obtained for Ra=108. However, the flow reverts to unsteadiness for Ra=3×108. In this latter case, the instability is due to the vertical boundary layers. To cite this article: G. de Gassowski et al., C. R. Mecanique 331 (2003). [Copyright &y& Elsevier]

In a recent paper, Aubin and Coulouvrat (1998) dealt with equations of motion in the fluid in relaxation – mathematically: Burgers' equations, physically: continuity equations, Navier–Stokes equations, energy bilance, and equations of relaxation. A related equation of Ginzburg–Landau type (1965) extended for the kinetic depinning transitions takes its form (0)∂m/∂t=J∂2m/∂z2−V∂m/∂z−Am−Cm3. The present authors are interested in an analogue of (0) for (x,t,τ)∈R5,R9 or R13 with x∈R3,R7 or R11, respectively, with space or temporal character of τ [L̷awrynowicz and Suzuki (2000)]: ds2=−dx12−⋯−dxp2−λdτ2+c2dt2withλ=1or−1;p=3,7or11. Hence, they investigate the equations of the form (1)∂u/∂t=bΔp+λ∂2/∂τ2u+ηwithλ=1or−1;Δp=∂2/∂x12+⋯+∂2/∂xp2=J∂2m/∂z2−V∂m/∂z−Am−Cm3. The present authors are interested in an analogue of (0) for (x,t,τ)∈R5,R9 or R13 with x∈R3,R7 or R11, respectively, with space or temporal character of τ [L̷awrynowicz and Suzuki (2000)]: ds2=−dx12−⋯−dxp2−λdτ2+c2dt2withλ=1or−1;p=3,7or11. Hence, they investigate the equations of the form (1)∂u/∂t=bΔp+λ∂2/∂τ2u+ηwithλ=1or−1;Δp=∂2/∂x12+⋯+∂2/∂xp2−V∂m/∂z−Am−Cm3. The present authors are interested in an analogue of (0) for (x,t,τ)∈R5,R9 or R13 with x∈R3,R7 or R11, respectively, with space or temporal character of τ [L̷awrynowicz and Suzuki (2000)]: ds2=−dx12−⋯−dxp2−λdτ2+c2dt2withλ=1or−1;p=3,7or11. Hence, they investigate the equations of the form (1)∂u/∂t=bΔp+λ∂2/∂τ2u+ηwithλ=1or−1;Δp=∂2/∂x12+⋯+∂2/∂xp2−Am−Cm3. The present authors are interested in an analogue of (0) for (x,t,τ)∈R5,R9 or R13 with x∈R3,R7 or R11, respectively, with space or temporal character of τ [L̷awrynowicz and Suzuki (2000)]: ds2=−dx12−⋯−dxp2−λ dτ2+c2 dt2 with λ=1 or −1; p=3,7 or 11. Hence, they investigate the equations of the form (1)∂u/∂t=bΔp+λ∂2/∂τ2u+ηwithλ=1or−1;Δp=∂2/∂x12+⋯+∂2/∂xp2=bΔp+λ∂2/∂τ2u+ηwithλ=1or−1;Δp=∂2/∂x12+⋯+∂2/∂xp2u+η with λ=1 or −1;Δp=∂2/∂x12+⋯+∂2/∂xp2+⋯+∂2/∂xp2, p=2,3,…, and their generalizations related to the generalized d'Alembertian □pλ=Δp+λ∂2/∂τ2. [Copyright &y& Elsevier]

This paper is devoted to the study of the existence of positive solutions of semilinear Dirichlet eigenvalue problems for diffusive logistic equations with discontinuous coefficients which model population dynamics in environments with spatial heterogeneity. The approach here is distinguished by the extensive use of the ideas and techniques characteristic of the recent developments in the theory of singular integral operators. Moreover, we make use of an Lp variant of an estimate for the Green operator of the Dirichlet problem introduced in the study of Feller semigroups. [Copyright &y& Elsevier]

This paper deals with the study of the stationary, incompressible, 2D flow of a fluid in a thin wavy tube. In this work, we consider a domain which is the union of two wavy tubes depending on a small parameter. The asymptotic expansion is constructed. The method of partial asymptotic decomposition is applied. The numerical implementation of this method for the extrusion process is developed. The new physical effects are discussed. To cite this article: A. Ainser et al., C. R. Mecanique 331 (2003). [Copyright &y& Elsevier]

Regarding the present rate of species extinction, preservation of biodiversity has become a prerequisite to achieve sustainable development. Among major challenges an urgent need in research in biological conservation is required to reach this goal. Protected areas deserve special importance due to their relevance for development of research both in fundamental and applied ecology. This papers aims at making a critical review of possibilities and priorities in conservation ecology in these areas. To cite this article: F. Ramade, C. R. Biologies 326 (2003). [Copyright &y& Elsevier]

Butterfly pigmentation patterns are one of the most spectacular and vivid examples of pattern formation in biology. They have attracted much attention from experimentalists and theoreticians, who have tried to understand the underlying genetic, chemical and physical processes that lead to patterning. In this paper, we present a brief review of this field by first considering the generation of the localised, eyespot, patterns and then the formation of more globally controlled patterns. We present some new results applied to pattern formation on the wing of the mimetic butterfly Papilio dardanus. To cite this article: H.F. Nijhout et al., C. R. Biologies 326 (2003). [Copyright &y& Elsevier]

We describe a wavelet collocation method of computing numerical solutions to evolution equations that inherit energy conservation law. This method is based on the wavelet sampling approximation with Coifman scaling systems combined with the generalized energy integrals. In this paper, we shall focus on the theoretical background of our approach. [Copyright &y& Elsevier]

Application of the fuzzy set theory to the biometric evaluation of the species Nummulites millecaput in the western part of the Tethys. The goal of this paper is to demonstrate the ability of the fuzzy-set theory to contribute to the evaluation of paleontological problems. As an example, the species Nummulites millecaput, Boube´e has been chosen. One hundred specimens of this species, collected from four localities (Arrimblar, Adelholzen, Dudar, and Mount-Kotuc) have been prepared (equatorial sections) for the biometric measurement of the external and internal characteristics. First a traditional statistical evaluation was performed, followed by the construction of membership functions, the latter ones expressing in the best way the transitions from one locality to the other. The results of this evaluation confirmed that from Aquitaine (France) to Armenia, the same species – Nummulites millecaput – was distributed during the Eocene. To cite this article: G. Ba´rdossy et al., C. R. Palevol 2 (2003). [Copyright &y& Elsevier]

Nuclear energy has distinctive merits (sustainable resources, low costs, no greenhouse gases) but its development must overcome serious hurdles (fear of accidents, radiophobia, waste management). The large unit size of present-day reactors is compatible only with large electrical grids, and involves a high capital cost. Taking into account these different factors, the paper outlines how nuclear energy may contribute to the reduction of greenhouse gases, and which are the most promising developments. To cite this article: P. Bacher, C. R. Geoscience 335 (2003). [Copyright &y& Elsevier]

Consider the following general type of perturbed stochastic partial differential equations: Lu&epsiv;t,x=&epsiv;αu&epsiv;t,xF˙(t,x)+βu&epsiv;t,x, (t,x)∈R+×Rd, &epsiv;>0, with null initial conditions, L a second-order partial differential operator and F a Gaussian noise, white in time and correlated in space. In a previous work we proved the existence of smooth density pt,x&epsiv;(y), t>0, x∈Rd, for the law of the solution of above-mentioned equation. In this paper we study the logarithmic estimates for this density, that means to establish the behaviour of 2&epsiv;2logpt,x&epsiv;(y), as &epsiv;↓0. This kind of estimates is also called Varadhan–Le´andre estimates. [Copyright &y& Elsevier]

In this paper we discuss the influence of Gram–Schmidt orthonormalization for the computation of the rational representation in the asymptotic numerical method. Classical, modified and iterated Gram–Schmidt algorithms are compared using the ordinary and the mass scalar products. The accuracy of the proposed algorithms are tested on elastic shells. To cite this article: R. Jamai, N. Damil, C. R. Mecanique 331 (2003). [Copyright &y& Elsevier]

The sequential iterative approach (SIA) scheme is the most efficient method for modelling reactive transport in porous media with the operator-splitting approach. A combination of finite discontinuous and finite mixed-hybrid elements is a powerful method for solving solute transport in porous media, but the use of this method for SIA scheme induces numerical difficulties. In this paper, a new method is developed to solve reactive transport by using both the SIA scheme and a combination of finite discontinuous and finite mixed elements. The proposed method is tested by modelling a column experiment. To cite this article: J. Carrayrou et al., C. R. Mecanique 331 (2003). [Copyright &y& Elsevier]

This paper treats the interaction of a buoyancy induced convection flow and a free stream impinging at some angle of incidence on an inclined heated flat plate. It is shown that these mechanisms act to either reinforce or oppose one another. In the opposite case, a critical Grashof number exits above which the stagnation point is located behind the origin whatever the angle of attack. The linear stability of the resulting basic flow to three-dimensional disturbances are then analyzed. By using a proper scaling, it is found that the stability problem is governed by a modified Grashof number and therefore the stability characteristics can be reduced to those occurring in Hiemenz flow over a heated horizontal plate. [Copyright &y& Elsevier]

The purpose of the present paper is to offer a precise definition of the concepts of integration, emergence and complexity in biological networks through the use of the information theory. If two distinct properties of a network are expressed by two discrete variables, the classical subadditivity principle of Shannon''s information theory applies when all the nodes of the network are associated with these properties. If not, the subadditivity principle may not apply. This situation is often to be encountered with enzyme and metabolic networks, for some nodes may well not be associated with these two properties. This is precisely what is occurring with an enzyme that binds randomly its two substrates. This situation implies that an enzyme, or a metabolic network, may display a joint entropy equal, smaller, or larger than the corresponding sum of individual entropies of component sub-systems. In the first case, the collective properties of the network can be reduced to the individual properties of its components. Moreover, the network is devoid of any information. In the second case, the system displays integration effects, behaves as a coherent whole, and has positive information. But if the joint entropy of the network is smaller than the sum of the individual entropies of its components, then the system has emergent collective properties and can be considered complex. Moreover, under these conditions, its information is negative. The extent of negative information is enhanced if the enzyme, or the metabolic network, is far away from equilibrium. To cite this article: J. Ricard, C. R. Biologies 326 (2003). [Copyright &y& Elsevier]

Planar silica device technology provides the ability to filter, route, switch, and attenuate optical signals for Wavelength Division Multiplexing (WDM) based photonic networks. As network capacity expands there is a requirement to increase the complexity, scale and density of the functions whilst reducing cost. It is also important that both the optical performance and long term stability of the devices are not compromised. The following paper reviews recent progress on these types of devices for large-scale manufacture, concentrating on key performance parameters for filter type structures and hybrid integrated devices such as insertion loss and polarisation dependent loss (PDL). To cite this article: J.R. Bonar et al., C. R. Physique 4 (2003). [Copyright &y& Elsevier]

The development of atmospheric lightning is initiated by a ‘leader’ phase during which ionized channels appear in virgin air. The use of rapid cameras, the measure of fields and currents associated with the discharge allow one to compare the propagation of laboratory leaders with those of natural or artificially triggered lightning. The corresponding physical processes can be analyzed with the help of models developed for laboratory leaders provided that the non linear effects due to the intense current circulation leading to lightning leader thermalization are taken into account. A self-coherent simulation of triggered lightning leaders for both polarities is presented is this paper. Furthermore, these models make it possible to define the ‘stabilization field’ concept, equal to the minimum ambient field allowing the stable progress of a leader from a ground structure, expressed as a height and curvature function of this structure. This concept can be validated through triggered lightning tests. Finally, the stabilization field analysis is completed by a simplified analytical model based upon an electrostatic approach of propagation equilibrium. To cite this article: P. Lalande et al., C. R. Physique 3 (2002) 1375–1392. [Copyright &y& Elsevier]

Our long-range aim is to propose a forest fire simulator. To this end, we have developed a phenomenological model of fire spread. Then, we have improved it in order to take into account advective transfers thanks to a simplified flow. In this paper, we present in a synthetic way our modelling approach that can also be applied to other phenomenological models. Finally, we compare the model predictions to laboratory experiments. To cite this article: A. Simeoni et al., C. R. Mecanique 330 (2002) 783–790. [Copyright &y& Elsevier]

The analysis of mechanical structures using the Finite Element Method in the framework of large elastoplastic strain, needs frequent remeshing of the deformed domain during computation. Indeed, the remeshing is due to the large geometrical distortion of finite elements and the adaptation to the physical behavior of the solution. This paper gives the necessary steps to remesh a mechanical structure during large elastoplastic deformations with damage. An important part of this process is constituted by geometrical and physical error estimates. The proposed method is integrated in a computational environment using the ABAQUS/Explicit solver and the BL2D-V2 adaptive mesher. To cite this article: H. Borouchaki et al., C. R. Mecanique 330 (2002) 709–716. [Copyright &y& Elsevier]

In order to determine the radionuclides'' sorption constants on solid natural minerals, both thermodynamic and structural investigations, using spectroscopic techniques, are presented. The natural clays, that could be used as engineering barriers in the nuclear waste geological repository, are rather complex minerals. Therefore, in order to understand how these natural materials retain the radionuclides, it is necessary first to perform these studies on simple substrates such as single crystal, oxides and silicates, and then extrapolate the obtained results on the natural minerals. We examine in this paper the sorption processes of the hexavalent uranium on zircon (ZrSiO4) and the trivalent curium on a natural clay (bentonite). The corresponding sorption curves are simulated using the results obtained with the following spectroscopic techniques: laser induced spectrofluorimetry, X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (EXAFS), diffuse reflectance infrared Fourier transform (DRIFT). To cite this article: E. Simoni, C. R. Physique 3 (2002) 987–997. [ABSTRACT FROM AUTHOR]

In this paper we prove the existence of a solution for a class of non coercive nonlinear equations whose prototype is: −Δpu+b(x)&z.sfnc;∇u&z.sfnc;λ=μin Ω,u=0on ∂Ω, where Ω is a bounded open subset of RN, N&ges;2, Δp is the so called p-Laplace operator, 1, μ is a Radon measure with bounded variation on Ω, 0&les;λ&les;p−1 and b belongs to the Lorentz space LN,1(Ω). [Copyright &y& Elsevier]

The characterisation of the surface electrical properties of membrane materials is critical for understanding and predicting the filtration performances of membranes. In this paper, four simple experimental methods – streaming potential, electro-osmosis, pore conductivity and membrane potential –, allowing the characterisation of the charge state of membrane pore walls are presented. The four experimental parameters provide information about the sign of the electrical net charge. Examples illustrating the influence of the pH, electrolyte concentration and nature on the four experimental parameters are given. The zeta potential can be then deduced from these measurements by means of a model. [Copyright &y& Elsevier]

In this paper, we present a multi-agent framework for data mining in electromyography. This application, based on a web interface, provides a set of functionalities allowing to manipulate 1000 medical cases and more than 25000 neurological tests stored in a medical database. The aim is to extract medical information using data mining algorithms and to supply a knowledge base with pertinent information. The multi-agent platform gives the possibility to distribute the data management process between several autonomous entities. This framework provides a parallel and flexible data manipulation. [Copyright &y& Elsevier]

Surgical resection of hepatic tumours is not always possible, since it depends on different factors, among which their location inside the liver functional segments. Alternative techniques consist in local use of chemical or physical agents to destroy the tumour. Radio frequency and cryosurgical ablations are examples of such alternative techniques that may be performed percutaneously. This requires a precise localisation of the tumour placement during ablation. Computer-assisted surgery tools may be used in conjunction with these new ablation techniques to improve the therapeutic efficiency, whilst they benefit from minimal invasiveness. This paper introduces the principles of a system for computer-assisted hepatic tumour ablation and describes preliminary experiments focusing on data registration evaluation. To keep close to conventional protocols, we consider registration of pre-operative CT or MRI data to intra-operative echographic data. [Copyright &y& Elsevier]

This paper considers two methods for modelling delamination growth in laminated composite materials. The first one uses a fracture mechanics approach in which the energy release rate is computed with the θ-method under the assumption of large displacements. The second approach is based on the use of interface elements in which the progressive debonding is described through the introduction of a damage value. Both methods are compared to experiments and to analytical results on the example of a Double Cantilever Beam specimen. [Copyright &y& Elsevier]

This paper sums up some recent studies related to the numerical solution of boundary value problems deriving from Maxwell''s equations. These studies bring to light the theoretical origins of the ‘corner paradox’ pointed out by numerical experiments for years: In a domain surrounded by a perfect conductor, a ‘nodal’ discretization can approximate the electromagnetic field only if the domain has no reentrant corners or edges. The explanation lies in a mathematical curiosity: two different interpretations of the same variational equation, which are both well-posed and lead either to the physical or a spurious solution! Two strategies which were recently proposed to remedy this flaw of nodal elements are described. To cite this article: C. Hazard, C. R. Mecanique 330 (2002) 57–68 [Copyright &y& Elsevier]

A boundary value problem P&epsiv; related to a third order parabolic equation with a small parameter &epsiv; is analized. This equation models the one-dimensional evolution of many dissipative media as viscoelastic fluids or solids, viscous gases, superconducting materials, incompressible and electrically conducting fluids. Moreover, the third order parabolic operator regularizes various nonlinear second order wave equations. In this paper, the hyperbolic and parabolic behaviour of the solution of P&epsiv; is estimated by means of slow time τ=&epsiv;t and fast time θ=t/&epsiv;. As consequence, a rigorous asymptotic approximation for the solution of P&epsiv; is established. To cite this article: M. De Angelis, P. Renno, C. R. Mecanique 330 (2002) 21–26 [Copyright &y& Elsevier]

Brookhart and Gibson have recently described the synthesis of new iron and cobalt complexes with pyridine bis(imine) ligands for the polymerisation of ethylene and propylene. In the present paper, the synthesis of new complexes modified with heteroatoms, based on the above-mentioned catalysts, is reported. Higher activities are observed. The influence of the polymerisation temperature on the catalytic activity has been investigated. The first example of the successful copolymerisation of ethylene and 1-hexene with these catalysts is also discussed. The (co)polymers have been characterized by high temperature 13C NMR. To cite this article: R. Souane et al., C. R. Chimie 5 (2002) 43–48 [Copyright &y& Elsevier]