Optimization of sonic crystal attenuation properties by ev-MOGA multiobjective evolutionary algorithm

[EN] This paper shows a promising method for acoustic barrier design using a new acoustic material called Sonic Crystals (SCs). The configuration of these SCs is set as a multiobjective optimization problem which is very difficult to solve with conventional optimization techniques. The paper presents a new parallel implementation of a Multiobjective Evolutionary Algorithm called ev-MOGA (also known as (sic)-MOGA) and its application in a complex design problem. ev-MOGA algorithm has been designed to converge towards a reduced, but well distributed, representation of the Pareto Front (solution of the multiobjective optimization problem). The algorithm is presented in detail and its most important properties are discussed. To reduce the ev-MOGA computational cost when.Partially supported by MEC (Spanish Government) and FEDER funds: projects DPI2005-07835, MAT2006-03097 and Generalitat Valenciana (Spain) projects GV06/026, GV/2007/191Herrero Durá, JM.; Garcia-Nieto, S.; Blasco, X.; Romero García, V.; Sánchez Pérez, JV.; García-Raffi, LM. (2009). Optimization of sonic crystal attenuation properties by ev-MOGA multiobjective evolutionary algorithm. Structural and Multidisciplinary Optimization. 39(2):203-215. https://doi.org/10.1007/s00158-008-0323-7S203215392Alander J (2002) An indexed bibliography of genetic algorithms & pareto and constrainedoptimization. Tech Rep, Dpt of Information Technology, University of VaasaCantú-Paz E (1997) A survey of parallel genetic algorithms. Tech Rep 97003, Illimois Genetic Algorithms LaboratotyCervera F, Sanchis L, Sánchez-Pérez JV, Martínez-Sala R, Rubio C, Meseguer F, López C, Caballero D, Sánchez-Dehesa J (2002) Refractive acoustic devices for airborne sound. 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Appl Phys Lett 86:0541021–0541023Herrero J, Blasco X, Martínez M, Ramos C, Sanchis J (2007) Non-linear robust identification of a greenhouse model using multi-objective evolutionary algorithms. Biosyst Eng 98(3):335–346Herrero JM (2006) Non-linear robust identification using evolutionary algorithms. PhD thesis, Universidad Politécnica de Valencia, ValenciaHussein MI, Hamza K, Hulbert GM, Saitou K (2007) Optimal synthesis of 2d phononic crystals for broadband frequency isolation. Waves Random Complex Media 17(4):491–510Hussein MI, Hamza K, Hulbert GM, Scott RA, Saitou K (2006) Multiobjective evolutionary optimization of periodic layered materials for desired wave dispersion characteristics. Struct Multidisc Optim 31:60–75Kafesaki M, Economou E (1999) Multiple scattering theory for three-dimensional periodic acoustic composites. Phys Rev B 60:11993Kohn W, Rostoker N (1954) Solution of the schrodinger equation in periodic lattices with an aplication to metallic lithium. Phys Rev 94:1111Korringa J (1947) On th calculation of the energy of a bloch wave in a metal. Physica XIII:392Kushwaha M (1997) Stop-bands for periodic metallic rods: Sculptures that can filter the noise. Appl Phys Lett 70:3218–3220Laumanns M, Thiele L, Deb K, Zitzler E (2002) Combining convergence and diversity in evolutionary multi-objective optimization. Evol Comput 10(3):263–282Martínez-Sala R, Sancho J, Sánchez J, Gómez V, Llinares J, Meseguer F (1995) Sound attenuation by sculpture. Nature 378:241Miettinen KM (1998) Nonlinear multiobjective optimization. Kluwer, DordrechtMishra S, Deb K, Mohan M (2005) Evaluating the ε-domination based multi-objective evolutionary algorithm for a quick computation of pareto-optimal solutions. Evol Comput 13(4):501–526Romero-García V, Fuster E, García-Raffi LM, Sánchez-Pérez EA, Sopena M, Llinares J, Sánchez-Pérez JV (2006) Band gap creation using quasiordered structures based on sonic crystals. 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Brucella ceti infection in dolphins from the Western Mediterranean sea

Background: Brucella ceti infections have been increasingly reported in cetaceans. Brucellosis in these animals is associated with meningoencephalitis, abortion, discospondylitis’, subcutaneous abscesses, endometritis and other pathological conditions B. ceti infections have been frequently described in dolphins from both, the Atlantic and Pacific Oceans. In the Mediterranean Sea, only two reports have been made: one from the Italian Tyrrhenian Sea and the other from the Adriatic Sea. Results: We describe the clinical and pathological features of three cases of B. ceti infections in three dolphins stranded in the Mediterranean Catalonian coast. One striped dolphin had neurobrucellosis, showing lethargy, incoordination and lateral swimming due to meningoencephalitis, A B. ceti infected bottlenose dolphin had discospondylitis, and another striped dolphin did not show clinical signs or lesions related to Brucella infection. A detailed characterization of the three B. ceti isolates was performed by bacteriological, molecular, protein and fatty acid analyses. Conclusions: All the B. ceti strains originating from Mediterranean dolphins cluster together in a distinct phylogenetic clade, close to that formed by B. ceti isolates from dolphins inhabiting the Atlantic Ocean. Our study confirms the severity of pathological signs in stranded dolphins and the relevance of B. ceti as a pathogen in the Mediterranean Sea

Isolation of Neisseria meningitidis strains with increase of penicillin minimal inhibitory concentrations

We report the isolation and characterization of ten strains showing an increase in the minimal inhibitory concentrations to penicillin (MICs > 0·1 μg/ml), and describe the epidemiological, clinical and microbiological features. The susceptibility of 3432 meningococcal strains isolated from patients in the recent epidemic wave (1978–86) in Spain, to several antimicrobial agents used in the treatment and chemoprophylaxis of meningococcal infection has been tested. Most were resistant to sulphadiazine but sensitive to other antibiotics. The possible existence of a new pattern of behaviour of meningococcal to penicillin is discussed

High optimization process for increasing the attenuation properties of acoustic metamaterials by means of the creation of defects

Copyright (2008) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics along with the following message: The following article appeared in “Romero García, V.; Sánchez Pérez, JV.; García-Raffi, LM.; Herrero Durá, JM.; S. Garcia-Nieto; Blasco Ferragud, FX. (2008). High optimization process for increasing the attenuation properties of acoustic metamaterials by means of the creation of defects. Applied Physics Letters. 93:2235021-2235023” and may be found at http://dx.doi.org/10.1063/1.3040317. Authors own version of final article on e-print serversAn improvement in the attenuation capabilities of acoustic metamaterials by means of the creation of defects is considered here as a multiobjective optimization problem. From this point of view, it is possible to define the optimum strategy in the creation of defects to achieve an important increase in acoustic attenuation in a predetermined range of frequencies. A powerful multiobjective optimization algorithm called evMOGA has been used to solve this problem. The study has been restricted to the case of a two-dimensional sonic crystal formed by rigid cylinders in air, the defects being vacancies in the initial structure.This work was partially supported by MEC (Spanish Government) and FEDER funds: Project Nos. 419DPI2005-07835 and MAT2006-03097 and Generalitat Valenciana Project Nos. GV06/026 and GV/2007/191.Romero García, V.; Sánchez Pérez, JV.; García-Raffi, LM.; Herrero Durá, JM.; García Nieto, S.; Blasco Ferragud, FX. (2008). High optimization process for increasing the attenuation properties of acoustic metamaterials by means of the creation of defects. Applied Physics Letters. 93(22):2235021-2235023. https://doi.org/10.1063/1.3040317S223502122350239322Fang, N., Xi, D., Xu, J., Ambati, M., Srituravanich, W., Sun, C., & Zhang, X. (2006). Ultrasonic metamaterials with negative modulus. Nature Materials, 5(6), 452-456. doi:10.1038/nmat1644Torrent, D., & Sánchez-Dehesa, J. (2008). Anisotropic mass density by two-dimensional acoustic metamaterials. New Journal of Physics, 10(2), 023004. doi:10.1088/1367-2630/10/2/023004Sánchez-Pérez, J. V., Caballero, D., Mártinez-Sala, R., Rubio, C., Sánchez-Dehesa, J., Meseguer, F., … Gálvez, F. (1998). Sound Attenuation by a Two-Dimensional Array of Rigid Cylinders. Physical Review Letters, 80(24), 5325-5328. doi:10.1103/physrevlett.80.5325Fokin, V., Ambati, M., Sun, C., & Zhang, X. (2007). Method for retrieving effective properties of locally resonant acoustic metamaterials. Physical Review B, 76(14). doi:10.1103/physrevb.76.144302Sanchez-Perez, J. V., Rubio, C., Martinez-Sala, R., Sanchez-Grandia, R., & Gomez, V. (2002). Acoustic barriers based on periodic arrays of scatterers. Applied Physics Letters, 81(27), 5240-5242. doi:10.1063/1.1533112Torrent, D., & Sánchez-Dehesa, J. (2007). Acoustic metamaterials for new two-dimensional sonic devices. New Journal of Physics, 9(9), 323-323. doi:10.1088/1367-2630/9/9/323Romero-García, V., Fuster, E., García-Raffi, L. M., Sánchez-Pérez, E. A., Sopena, M., Llinares, J., & Sánchez-Pérez, J. V. (2006). Band gap creation using quasiordered structures based on sonic crystals. Applied Physics Letters, 88(17), 174104. doi:10.1063/1.2198012Herrero, J. M., Blasco, X., Martínez, M., Ramos, C., & Sanchis, J. (2007). Non-linear robust identification of a greenhouse model using multi-objective evolutionary algorithms. Biosystems Engineering, 98(3), 335-346. doi:10.1016/j.biosystemseng.2007.06.004Kafesaki, M., & Economou, E. N. (1999). Multiple-scattering theory for three-dimensional periodic acoustic composites. Physical Review B, 60(17), 11993-12001. doi:10.1103/physrevb.60.11993Ehrgott, M., & Tenfelde-Podehl, D. (2003). Computation of ideal and Nadir values and implications for their use in MCDM methods. European Journal of Operational Research, 151(1), 119-139. doi:10.1016/s0377-2217(02)00595-7Coello Coello, C. A., Van Veldhuizen, D. A., & Lamont, G. B. (2002). Evolutionary Algorithms for Solving Multi-Objective Problems. Genetic Algorithms and Evolutionary Computation. doi:10.1007/978-1-4757-5184-

Hole distribution in phononic crystals: design and optimization

An exhaustive study has been made into the potential improvement in attenuation and focusing of phononic crystal arrays resulting from the deliberate creation of vacancies. Use is made of a stochastic search algorithm based on evolutionary algorithms called the epsilon variable multi-objective genetic algorithm which, in conjunction with the application of multiple scattering theory, enables the design of devices for effectively controlling sound waves. Several parameters are analyzed, including the symmetries used in the distribution of holes and the optimum number of holes. The validity and utility of the general rules obtained have been confirmed experimentally.This work was partially supported by MEC (Spanish Government) and FEDER funds: Project Nos. 419DPI2005-07835, and MAT2006-03097 and Generalitat Valenciana Project Nos. GV06/026 and 420 GV/2007/191. The authors would like to thank John Rawlins (associate member of the Institute of Translation and Interpreting (No. 9743) of UK, and "Certified PRO" of ProZ according to the EN 15038) for his help with the use of English.Romero García, V.; Sánchez Pérez, JV.; García Raffi, LM.; Herrero Durá, JM.; García Nieto, S.; Blasco, X. (2009). Hole distribution in phononic crystals: design and optimization. Journal of the Acoustical Society of America. 125(6):3774-3783. https://doi.org/10.1121/1.3126948S37743783125

Deep Molecular Characterization of Milder Spinal Muscular Atrophy Patients Carrying the c.859G>C Variant in SMN2

Spinal muscular atrophy (SMA) is a severe neuromuscular disorder caused by biallelic loss or pathogenic variants in the SMN1 gene. Copy number and modifier intragenic variants in SMN2, an almost identical paralog gene of SMN1, are known to influence the amount of complete SMN proteins. Therefore, SMN2 is considered the main phenotypic modifier of SMA, although genotype-phenotype correlation is not absolute. We present eleven unrelated SMA patients with milder phenotypes carrying the c.859G>C-positive modifier variant in SMN2. All were studied by a specific NGS method to allow a deep characterization of the entire SMN region. Analysis of two homozygous cases for the variant allowed us to identify a specific haplotype, Smn2-859C.1, in association with c.859G>C. Two other cases with the c.859G>C variant in their two SMN2 copies showed a second haplotype, Smn2-859C.2, in cis with Smn2-859C.1, assembling a more complex allele. We also identified a previously unreported variant in intron 2a exclusively linked to the Smn2-859C.1 haplotype (c.154-1141G>A), further suggesting that this region has been ancestrally conserved. The deep molecular characterization of SMN2 in our cohort highlights the importance of testing c.859G>C, as well as accurately assessing the SMN2 region in SMA patients to gain insight into the complex genotype-phenotype correlations and improve prognostic outcomes

Cancer incidence in heart transplant recipients with previous neoplasia history

[Abstract] Neoplasm history increases morbidity and mortality after solid organ transplantation and has disqualified patients from transplantation. Studies are needed to identify factors to be considered when deciding on the suitability of a patient with previous tumor for heart transplantation. A retrospective epidemiological study was conducted in heart transplant (HT) recipients (Spanish Post–Heart Transplant Tumor Registry) comparing the epidemiological data, immu-nosuppressive treatments and incidence of post-HT tumors between patients with previous malignant noncardiac tumor and with no previous tumor (NPT). The impact of previous tumor (PT) on overall survival (OS) was also assessed. A total of 4561 patients, 77 PT and 4484 NPT, were evaluated. The NPT group had a higher proportion of men than the PT group (p < 0.001). The incidence of post-HT tumors was 1.8 times greater in the PT group (95% confidence interval [CI] 1.2–2.6; p < 0.001), mainly due to the increased risk in patients with a previous hematologic tumor (rate ratio 2.3, 95% CI 1.3–4.0, p < 0.004). OS during the 10-year posttransplant period was significantly lower in the PT than the NPT group (p = 0.048) but similar when the analysis was conducted after a first post-HT tumor was diagnosed. In conclusion, a history of PT increases the incidence of post-HT tumors and should be taken into account when considering a patient for HT

The Falling Incidence of Hematologic Cancer After Heart Transplantation

[Abstract] Background. A number of changes in the management of heart transplantation (HT) patients have each tended to reduce the risk of post-HT hematologic cancer, but little information is available concerning the overall effect on incidence in the HT population. Methods. Comparison of data from the Spanish Post-Heart-Transplantation Tumour Registry for the periods 1991–2000 and 2001–2010. Results. The incidence among patients who underwent HT in the latter period was about half that observed in the former, with a particularly marked improvement in regard to incidence more than five yr post-HT. Conclusions. Changes in HT patient management have jointly reduced the risk of hematologic cancer in the Spanish HT population. Long-term risk appears to have benefited more than short-term risk

Comparison between Spanish young and elderly people evaluated using Rivermead Behavioural Memory Test

The first objective of this work was to compare scores obtained in the daily memory function between young and elderly people, and to check whether there are differences between the groups for each of the profile scores obtained in the memory test. A second aim of this paper is to study the relationship between everyday memory and age, while controlling for gender and educational level. The total and profile scores obtained in the Rivermead Behavioural Memory Test were compared in a sample of 60 young and 120 elderly people from Valencia (Spain). Results showed significant differences between the two groups: those between 18 and 30 years obtained a higher average than those over 65. Once the group comparison was controlled for gender and educational level, the statistical effect of age group disappeared. The non-significant effect of group can not be explained by the introduction of gender, because both its main effect and the interaction were not statistically significant. However, educational level had a statistically significant effect which may explain the non-significant effect of group in this new analysis. The main conclusion is the need to carefully control for educational level in all studies related with everyday memory and ageing, as the differences found could be due to generational differences more than to biological deterioratio