Double (implicit and explicit) dependence of the electromagnetic field of an accelerated charge on time: Mathematical and physical analysis of the problem

We considered the electromagnetic field of a charge moving with a constant acceleration along an axis. We found that this field obtained from the Li\'enard-Wiechert potentials does not satisfy Maxwell equations if one considers exclusively a retarded interaction (i.e. pure implicit dependence this field on time). We show that if and only if one takes into account both retarded interaction and direct interaction (so called "action-at-a-distance") the field produced by an accelerated charge satisfies Maxwell equations.Comment: ReVTeX file, no figures, 12p

Capacités de traitement d'un effluent de synthèse en infiltration percolation

Dans cet article, nous présentons des travaux mettant en évidence les capacités de traitement biologique des eaux résiduaires urbaines au sein des milieux poreux de textures différentes. Une étude comparative du développement de la biomasse couplé aux mécanismes généraux de transferts gazeux à travers deux réacteurs biologiques est menée. Des lits d’infiltration percolation sont simulés par des colonnes garnies de sables d’origine et de structures différentes. Ils sont alimentés périodiquement via un automate de commande avec un influent d’une charge de 525 mgDCO/l et de 54 mgNK/l. Les résultats obtenus établissent le fait qu’un développement équilibré de la biomasse incluant les phases de croissance et de régression est intrinsèquement lié à la nature physique du matériau support. A l’aide des carottes prélevées sur les massifs filtrants et des sondes d’oxymétrie introduites à différentes hauteurs des lits d’infiltration, nous montrons que la répartition verticale du biofilm dans les colonnes ainsi que l’oxygénation des milieux poreux lors des périodes de repos sont également corrélées à la structure des supports pourtant de diamètres moyens similaires. L’efficacité de traitement biologique du carbone est supérieure pour un sable d’origine alluvionnaire comparativement à un sable concassé ; la tendance s’inversant significativement lorsqu’il s’agit de la diminution de l’azote.In this article, we present work highlighting the capacity of variously textured porous media to biologically process urban waste water. A comparative study was undertaken that coupled biomass development with general gas transfer mechanisms through two biological engines.Infiltration/percolation beds are biological systems that treat water using a purifying bacterial culture that develops on a mineral support. Used in domestic wastewater treatment, they are regarded as being well suited to rural areas. These infiltration/percolation beds are easy to use and attain a high quality in their output, two factors that constitute assets for small communities.Infiltration/percolation beds were simulated in the present work by columns lined with sands of varying origin and structure. They were fed automatically, at set intervals, with waste water containing 525 mg/L of dissolved organic carbon (DOC) and 54 mg/L of Kjeldahl nitrogen. A balanced development of the biomass, including the phases of growth and regression, was intrinsically related to the physical nature of the material used as a support. First, during the supply period, balanced growth of the biomass was quickly reached within the crushed sand. Secondly, within round sand, the regression of the biofilm was less significant and more regular over several weeks. In both supports, the regression was well correlated with an exponential decay. Lastly, the frequency of the supply periods, the organic loads involved, and the rest periods imposed are all factors that contribute to a lack of accumulation of living and/or inert organic matter in the columns.After obtaining a balanced development of the biomass, the abilities of the columns to reduce the concentrations of carbon, Kjeldahl nitrogen and ammonia were evaluated. Samples of effluent were taken downstream, both before the beginning of the supply period and as it came out of the column approximately thirty minutes after beginning the drainage period. The percentage of suspended matter coming out of the columns gave rather precise information on the scrubbing of the solid mass caused by various shearing speeds or by the structure of the base.Generally, it appeared that :- The reduction of the overall DOC was higher than 70%, regardless of which type of sand base was used.- In the water coming out of the column made up of round sand, the overall DOC content was without exception lower than 125 mg/L, as would be expected for an infiltration-percolation process.- The treatment of carbon in the columns based on stream sand was in general more effective than that obtained in columns with crushed sand.Concerning the treatment of nitrogen, crushed sand yielded outputs with a reduction in ammonia that was a lot higher than 80% (mean ± SD: 92 ± 4%) and was systematically higher than those obtained with stream sand (mean ± SD: 72 ± 7%). The suspended matter content was extremely low in the effluent; since no suspended matter was introduced into the effluent, the concentration coming out of the column was the direct result of the biofilm becoming detached and/or, to a lesser extent, of the transport of the biomass in the liquid phase. As could be expected, because of the roughness causing more shearing, more particles became detached when the interior solid mass was made up of crushed sand.Using core samples taken from the filter's solid mass, as well as oxygen probes inserted at various levels into the biological engines, we showed that the vertical distribution of the biofilm in the columns, as well as the oxygenation of the porous media during the rest periods, were all correlated with the structure of the solid supports (note that all sands had similar average diameters). Gaseous exchanges within the filter's solid mass were dependent on both the type of coating and the depth at which they took place. The oxygen probes were inserted at depths of 14 cm and 18 cm respectively, to determine the percentage of oxygen saturation in the liquid phase within the filter during one week while the columns were operating. Two phases were characteristic of the exchanges observed in the upper part of the filter's solid mass. First we noted an instantaneous reduction in the oxygen content of the liquid phase, linked to the arrival of a batch, followed by a reoxygenation of this portion. Next there was a long phase, lasting approximately 94% of the time between batches, during which time the oxygen content in the residual moisture remained constant. In the lower part of the solid mass, variation in oxygen content was different. Partial deoxygenation in the liquid phase of the porous media here was primarily due to the biochemical oxidation of the organic matter (i.e., consumption by the biomass). It was also due, to a lesser extent, to the augmentation in moisture content that occurs after each batch, and leads to a reduction in porosity and a decrease in oxygen transfer. During the final phase of drainage, a balance was created between the open porous space with air, and the space containing stagnant moisture. The diffusion of oxygen in the former and its transfer towards the latter thus compensated for this consumption, and it therefore remained constant. If the medium was left to dry out longer, the diffusion and transfer phenomena increased, and we observed an increase in oxygen content.With respect to the vertical distribution of biomass in the columns, we found that it was almost homogeneous inside the stream sand, up to a depth of 28 cm (total depth = 40 cm). Generally, the organic matter content at each point of measurement in the column was higher in the stream sand than in the crushed sand. The variation was greater around 28 cm, where there was a more significant quantity of moisture inside the sand

Action at a distance as a full-value solution of Maxwell equations: basis and application of separated potential's method

The inadequacy of Li\'{e}nard-Wiechert potentials is demonstrated as one of the examples related to the inconsistency of the conventional classical electrodynamics. The insufficiency of the Faraday-Maxwell concept to describe the whole electromagnetic phenomena and the incompleteness of a set of solutions of Maxwell equations are discussed and mathematically proved. Reasons of the introduction of the so-called ``electrodynamics dualism concept" (simultaneous coexistence of instantaneous Newton long-range and Faraday-Maxwell short-range interactions) have been displayed. It is strictly shown that the new concept presents itself as the direct consequence of the complete set of Maxwell equations and makes it possible to consider classical electrodynamics as a self-consistent and complete theory, devoid of inward contradictions. In the framework of the new approach, all main concepts of classical electrodynamics are reconsidered. In particular, a limited class of motion is revealed when accelerated charges do not radiate electromagnetic field.Comment: ReVTeX file, 24pp. Small corrections which do not have influence results of the paper. Journal reference is adde

Sex pheromone biosynthetic pathways are conserved between moths and the butterfly Bicyclus anynana

Although phylogenetically nested within the moths, butterflies have diverged extensively in a number of life history traits. Whereas moths rely greatly on chemical signals, visual advertisement is the hallmark of mate finding in butterflies. In the context of courtship, however, male chemical signals are widespread in both groups although they likely have multiple evolutionary origins. Here, we report that in males of the butterfly Bicyclus anynana, courtship scents are produced de novo via biosynthetic pathways shared with females of many moth species. We show that two of the pheromone components that play a major role in mate choice, namely the (Z)-9-tetradecenol and hexadecanal, are produced through the activity of a fatty acyl Δ11-desaturase and two specialized alcohol-forming fatty acyl reductases. Our study provides the first evidence of conservation and sharing of ancestral genetic modules for the production of FA-derived pheromones over a long evolutionary timeframe thereby reconciling mate communication in moths and butterflies