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1.
This paper reports on statistics concerning production and consumption of packaging (as a whole or per capita) in Europe, in the USA, in Japan and in the world. Data have been provided by National Trade Associations and by consultants specialized in packaging and in economics. It is estimated that in 1986 the global consumption of packaging reached 150 millions of tonnes valued at 1200 billions of French francs. Consumption could reach 247 million tonnes by the year 2000. Paper and board have the highest consumption rate, but plastics have the highest rate of growth. Nevertheless, consumption per capita in the industrialized countries will be more than 10 times the consumption in underdeveloped countries. The packaging industries take fourth place in the USA, sixth in Western Germany and twelfth in France. In Europe, as in the world, paper and board is the material most used (40%), with glass (a high density material) taking second place and plastics third, i.e. if we consider the quantity of materials and not their value. Some differences appear between the various countries, but the figures for USA and Japan lead to similar conclusions. The survey shows clearly that the USA as compared with Europe has twice the consumption of packaging materials per capita and this difference is even greater compared with the rest of the world. 相似文献
2.
The liver microsomal Δ9 and Δ6 desaturase activities have been studied in rats with carbon tetrachloride-induced hepatitis. Immediately after poisoning,
significant decreases were observed for both types of desaturase activity. However, recovery kinetics were slower for the
Δ6 desaturase than for the Δ9 desaturase. The activities of NADH-ferricyanide and NADH-cytochrome C reductases, proteins involved in the electron transfers
associated with microsomal desaturation, were also measured. There was a fall in both activities after poisoning, but this
decrease was less than that of the desaturase activities. 相似文献
3.
Jean-Paul Brichta Aden N. Seaman Joseph H. Sanderson 《Computer Physics Communications》2009,180(2):197-200
A simplex algorithm used to solve molecular structure from asymptotic momentum values is reported. The geometry of molecular ions in linear and bent configurations is reconstructed. A polyatomic molecular ion with trigonal planar symmetry is used to demonstrate the scalability of the algorithm. 相似文献
4.
Israel Becerra Rafael Murrieta-Cid Raul Monroy Seth Hutchinson Jean-Paul Laumond 《Autonomous Robots》2016,40(2):395-423
In this paper, we address the problem of determining whether a mobile robot, called the pursuer, is able to maintain strong mutual visibility (a visibility notion between regions over a convex partition of the environment) of an antagonist agent, called the evader. We frame the problem as a non cooperative game. We consider the case in which the pursuer and the evader move at bounded speed, traveling in a known polygonal environment with or without holes, and in which there are no restrictions as to the distance that might separate the agents. Unlike our previous efforts (Murrieta-Cid et al. in Int J Robot Res 26:233–253, 2007), we give special attention to the combinatorial problem that arises when searching for a solution through visiting several locations in an environment with obstacles. In this paper we take a step further, namely, we assume an antagonistic evader who moves continuously and unpredictably, but with a constraint over its set of admissible motion policies, as the evader moves in the shortest-path roadmap, also called the reduced visibility graph (RVG). The pursuer does not know which among the possible paths over the RVG the evader will choose, but the pursuer is free to move within all the environment. We provide a constructive method to solve the decision problem of determining whether or not the pursuer is able to maintain strong mutual visibility of the evader. This method is based on an algorithm that computes the safe areas (areas that keep evader surveillance) at all times. We prove decidability of this problem, and provide a complexity measure to this evader surveillance game; both contributions hold for any general polygonal environment that might or not contain holes. All our algorithms have been implemented and we show simulation results. 相似文献
5.
A compressible model able to manage incompressible two-phase flows as well as compressible motions is proposed. After a presentation of the multiphase compressible concept, the new model and related numerical methods are detailed on fixed structured grids. The presented model is a 1-fluid model with a reformulated mass conservation equation which takes into account the effects of compressibility. The coupling between pressure and flow velocity is ensured by introducing mass conservation terms in the momentum and energy equations. The numerical model is then validated with four test cases involving the compression of an air bubble by water, the liquid injection in a closed cavity filled with air, a bubble subjected to an ultrasound field and finally the oscillations of a deformed air bubble in melted steel. The numerical results are compared with analytical results and convergence orders in space are provided. 相似文献
6.
Jean-Paul Arnaout 《Journal of Intelligent Manufacturing》2013,24(1):45-54
This paper addresses the Euclidean location-allocation problem with an unknown number of facilities, and an objective of minimizing the fixed and transportation costs. This is a NP-hard problem and in this paper, a three-stage ant colony optimization (ACO) algorithm is introduced and its performance is evaluated by comparing its solutions to the solutions of genetic algorithms (GA). The results show that ACO outperformed GA and reached better solutions in a faster computational time. Furthermore, ACO was tested on the relaxed version of the problem where the number of facilities is known, and compared to existing methods in the literature. The results again confirmed the superiority of the proposed algorithm. 相似文献
7.
Myriam Janeth Salazar-Terreros Jean-Paul Vernot 《International journal of molecular sciences》2022,23(13)
Cellular senescence is recognized as a dynamic process in which cells evolve and adapt in a context dependent manner; consequently, senescent cells can exert both beneficial and deleterious effects on their surroundings. Specifically, senescent mesenchymal stromal cells (MSC) in the bone marrow (BM) have been linked to the generation of a supporting microenvironment that enhances malignant cell survival. However, the study of MSC’s senescence role in leukemia development has been straitened not only by the availability of suitable models that faithfully reflect the structural complexity and biological diversity of the events triggered in the BM, but also by the lack of a universal, standardized method to measure senescence. Despite these constraints, two- and three dimensional in vitro models have been continuously improved in terms of cell culture techniques, support materials and analysis methods; in addition, research on animal models tends to focus on the development of techniques that allow tracking leukemic and senescent cells in the living organism, as well as to modify the available mice strains to generate individuals that mimic human BM characteristics. Here, we present the main advances in leukemic niche modeling, discussing advantages and limitations of the different systems, focusing on the contribution of senescent MSC to leukemia progression. 相似文献
8.
Rabeh Slimani Nacer Zazi Jean-Paul Chopart 《Protection of Metals and Physical Chemistry of Surfaces》2016,52(1):111-118
In this work a special regard is given to the morphology of the nickel deposited layers, onto AA1370 aluminum section and central longitudinal surfaces, with and without a weak magnetic field oriented in parallel and perpendicular to the coated surface in modified Watt bath. The obtained results show the formation of honeycomb structure nickel deposits for samples treated with weak parallel oriented field under approximately 0.3 A/cm2, and partial dendritic structure nickel deposit for samples treated with weak perpendicular oriented magnetic field, the perimeter deposits with and without magnetic field is different to the deposits in the remain surface. We attributed the defect of nickel deposits on the surfaces with and without magnetic field to the distribution of the intermetallics particles and we attributed the honeycomb structure to the escapement of hydrogen and oxygen. 相似文献
9.
Taleb Samia Dokhan Nahed Zazi Nacer Chopart Jean-Paul 《Protection of Metals and Physical Chemistry of Surfaces》2019,55(4):781-788
Protection of Metals and Physical Chemistry of Surfaces - In this work the effect of the permanent weak magnetic field on the electrodeposited ZnO nanostructured film on the ITO substrate... 相似文献
10.
Laura Grech Jean-Paul Ebejer Oriana Mazzitelli Kevin Schembri Joseph Borg Elisa Seria 《International journal of molecular sciences》2022,23(1)
Circulating bone marrow mesenchymal progenitors (BMMPs) are known to be potent antigen-presenting cells that migrate to damaged tissue to secrete cytokines and growth factors. An altered or dysregulated inflammatory cascade leads to a poor healing outcome. A skin model developed in our previous study was used to observe the immuno-modulatory properties of circulating BMMP cells in inflammatory chronic wounds in a scenario of low skin perfusion. BMMPs were analysed exclusively and in conjunction with recombinant tumour necrosis factor alpha (TNFα) and recombinant hepatocyte growth factor (HGF) supplementation. We analysed the expression levels of interleukin-8 (IL-8) and ecto-5′-nucleotidase (CD73), together with protein levels for IL-8, stem cell factor (SCF), and fibroblast growth factor 1 (FGF-1). The successfully isolated BMMPs were positive for both hemopoietic and mesenchymal markers and showed the ability to differentiate into adipocytes, chondrocytes, and osteocytes. Significant differences were found in IL-8 and CD73 expressions and IL-8 and SCF concentrations, for all conditions studied over the three time points taken into consideration. Our data suggests that BMMPs may modulate the inflammatory response by regulating IL-8 and CD73 and influencing IL-8 and SCF protein secretions. In conclusion, we suggest that BMMPs play a role in wound repair and that their induced application might be suitable for scenarios with a low skin perfusion. 相似文献