Synthesis of Filtering Structures for Microstrip Active Antennas Using Orlov's Formula

In this paper, a synthesis technique for nonuniform filtering structures to be employed in active integrated antenna layouts is presented. The idea is to suppress the higher harmonic contribution due to the presence of nonlinear components through a nonuniform transmission line properly designed via Orlov's synthesis formula. The theory presented is applied here to synthesize an amplifier‐based active antenna layout for wireless local area network (WLAN) purposes working at 2.4 GHz. The numerical results presented show the capabilities of the proposed approach.     

Carcass composition and meat characteristics of two rabbit breeds of different degrees of maturity

Carcass and meat characteristics of rabbits from two synthetic breeds of different size were compared. Breed R had a higher adult weight and reached slaughter weight 1 week before breed V. Sixty rabbits of each breed were slaughtered when they (approximately) reached the Spanish commercial liveweight of 2 kg in order to compare their carcasses and meat quality. The carcasses were measured and retailed according to the norms of the World Rabbit Scientific Association. Breed R had a considerably more developed liver, a less developed hind part, and a more developed thoracic cage. Dissectible fat content was 3.1% and 2.5% of the carcass weight for the breeds V and R, respectively. Meat content was higher in the V breed than in the R breed (53 and 51% with respect to the chilled carcases). The ratio meat bone was better for breed V (2.18 and 2.05, respectively). Muscular fat content, estimated in the meat of one side of the carcass, was higher for breed V. All these differences are related to the lower degree of maturity of breed R at equal weights. Muscular pH, measured on the B. femoris and on the M. Longissimus lumborum at the level of the 5th lumbar vertebra, was the same for both breeds. Colour was measured on the carcass surface and in cuts of the M. Longissimus lumborum. Some colour differences were found for the carcass surface, but not for the meat.     

Comparative analysis of a DI diesel engine fuelled with biodiesel blends during the European MVEG-A cycle: Performance and emissions (II)

The use of biodiesel is under evaluation as a possible fuel alternative to fossil fuels. Despite the literature available concerning the effect of biodiesel on engine performance and emissions under steady operation, there are not many research studies which cope with the effect of biodiesel during transient operation. Moreover, it is interesting to study the repercussions that the use of biodiesel has on complete vehicle performance and emissions. In this sense, the part 1 of the present paper deals with a preliminary analysis where the test facilities and procedures are explained, and the effects of the physicochemical properties of biodiesel on fuel injection are studied. To cope with the repercussion of the use of biodiesel in engine emissions during the MVEG-A cycle in this part of the paper a deep analysis of the pollutant emissions obtained during tests is done. Based on this analysis the paper also presents an approach to improve the engine control calibration to take advantage of utilising biodiesel.     

Estrogenic and androgenic activity of PCBs, their chlorinated metabolites and other endocrine disruptors estimated with two in vitro yeast assays

Investigations of environmental pollution by endocrine-disrupting chemicals are now in progress. Up to now, several in vitro bioassays have been developed for evaluation of the endocrine disruptive activity; however, there is still a lack of comparative studies of their sensitivity.In this work comparison of the estrogen screening assay based on β-galactosidase expression and a bioluminescent estrogen screen revealed differences in the sensitivity and specificity of the two tests. With the β-galactosidase screen a slight estrogen-like activity of Delor 103, a commercial mixture of PCB congeners, and a fungicide triclosan was measured whereas no activity was detected using the bioluminescent assay. A bioluminescent androgen test negated previously suggested androgenic potential of triclosan.Further, this work demonstrates the androgenic activity of Delor 103, with an EC₅₀ value of 2.29 × 10^− 2 mg/L. On the other hand, chlorobenzoic acids (CBAs), representing potential PCB degradation metabolites, exhibited no androgenic activity but were slightly estrogenic. Their estrogenicity varied with their chemical structure, with 2,3-CBA, 2,3,6-CBA, 2,4,6-CBA and monochlorinated compounds exhibiting the highest activity. Thus the results indicated possible transitions of the hormonal activity of PCBs during bacterial degradation.     

Development of new concepts for the control of polymerization processes: Multiobjective optimization and decision engineering. I. Application to emulsion homopolymerization of styrene

This article deals with the development of a multicriteria analysis, and its application to the optimization of batch emulsion polymerization processes. This new approach in the domain of polymer reaction engineering illustrates how a multiobjective optimization aided by a genetic algorithm and using the Pareto concept of domination is useful. In this process (emulsion homopolymerization of styrene), several objectives were simultaneously required, e.g., a high quality of the resulting products together with a high productivity. The aim of this study was to find the optimal experimental conditions to obtain simultaneously the minimum reaction time and designed values for both average molecular weights and particles size. To do that, an adapted mathematical model, able to describe all the process physicochemical phenomena, was been first elaborated. The multicriteria analysis then gave a set of nondominated points with conflicting criteria. A decision support system was then developed and applied to rank the Pareto solutions set and to propose some good solutions by taking into account the decision maker's preferences. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2383–2396, 2003     

Polyurethane from kraft lignin

The condensation of lignin with hexamethylene diisocyanate (HDI) or of a mixture of lignin-poly(ethylene oxide) (PEO) with HDI was investigated. The lignin used in this study was a kraft lignin from Pinus maritima, and was obtained from black liquor by acidification, filtration and vacuum drying. Thermogravimetric analysis was carried out to compare the weight loss against temperature of polyurethanes based on kraft lignin and hexamethylene diisocyanate, or of mixed polyurethanes lignin-PEO-HDI, with that of kraft lignin alone. It was shown that lignin can react with isocyanates in rather mild conditions to give polyurethanes, confirming previous results performed with model molecules. Some mechanical properties (Young's modulus and rupture strength) and glass transition temperature were also measured on the various above materials. In all cases it was concluded that lignin participates to the polycondensation reaction. As to rigid foams, it was found that polyurethanes prepared with oxypropylated glycerol, ethylene glycol and kraft lignin, in the weight proportions of 100/30/15, and HDI had good dimensional stability, and thermal and mechanical properties comparable to those of equivalent industrial materials.     

Real-time PCR-based methods for detection of Mycobacterium avium subsp. paratuberculosis in water and milk

A real-time PCR assay for quantitative detection of Mycobacterium avium paratuberculosis has been developed. It targets and amplifies sequences from the IS900 insertion element which is specific for this bacterium, and includes an internal amplification control. The assay was tested against 18 isolates of M. avium paratuberculosis, 17 other mycobacterial strains, and 25 non-mycobacterial strains, and was fully selective. It is capable of detecting <3 genomic DNA copies with 99% probability or alternatively, using cells directly in the reaction, 12 cells can be detected with 99% probability. Using prior centrifugation, the assay was able to consistently and quantifiably detect 10(2) M. avium paratuberculosis cells in 20 ml artificially contaminated drinking water. With a simple detergent and enzymatic sample pretreatment before centrifugation and nucleic acid extraction, the assay was able to consistently detect 10(2) M. avium paratuberculosis in 20 ml artificially contaminated semi-skimmed milk. The assay will be a useful addition to the range of diagnostic tools available for the study of M. avium paratuberculosis.     

Immuno-allergic hemolytic anemia connected with streptomycin

The distribution volume of 125l-diatrizoate in rat tissues was studied 5 seconds to 5 minutes after intravenous injection and 5 seconds to 2 minutes after intra-arterial injection. Immediately after injection, diatrizoate was distributed into a larger volume than plasma. Marked temporal changes in the distribution volume of individual tissues occurred during the first 2 minutes. At 5 minutes, the diatrizoate space approached the total extracellular fluid volume, with more than 80% of the contrast agent remaining outside the blood vessels. Thus the relative magnitude of contrast enhancement of a tissue appears to be related to the volume of the rapidly equilibrating extracellular space. Intra-arterial administration can significantly overload muscle with contrast material for about 2 minutes. This and other temporal changes in contrast distribution may prove useful in contrast-enhanced computed tomography using short scanning times.     

Two Triangulation Methods Based on Edge Refinement

In this paper two curvature adaptive methods of surface triangulation are presented. Both methods are based on edge refinement to obtain a triangulation compatible with the curvature requirements. The first method applies an incremental and constrained Delaunay triangulation and uses curvature bounds to determine if an edge of the triangulation is admissible. The second method uses this function also in the edge refinement process, i.e. in the computation of the location of a refining point, and in the re-triangulation needed after the insertion of this refining point. Results are presented, comparing both approaches.