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Our contribution in this paper is twofold. First, the global convergence analysis of the recently proposed pattern search implicit filtering algorithm (PSIFA), aimed at linearly constrained noisy minimization problems, is revisited to address more general locally Lipschitz objective functions corrupted by noise. Second, PSIFA is applied for solving the damped harmonic oscillator parameter identification problem. This problem can be formulated as a linearly constrained optimization problem, for which the constraints are related to the features of the damping. Such a formulation rests upon a very expensive objective function whose evaluation comprises the numerical solution of an ordinary differential equation (ODE), with intrinsic numerical noise. Computational experimentation encompasses distinct choices for the ODE solvers, and a comparative analysis of the most effective options against the pattern search and the implicit filtering algorithms.

Entomopathogenic nematodes (EPNs) from Heterorhabditidae and Steinernematidae families are extensively used to control insect pests. In Brazil, however, relatively few studies have identified and characterized these entomopathogens. The objective of this study was to identify and characterize an EPN isolate obtained from soil samples collected in the state of Paraná, Brazil. An isolate (UEL 08) of Heterorhabditis was detected in a soil sample collected from a pasture area cultivated with Brachiaria grass in Londrina, state of Paraná, Brazil (23°34ʹ311ʹʹS, 050°58ʹ298ʹʹW), using the insect-baiting technique with Galleria mellonella larvae as hosts. The nematode was identified through morphometric studies and molecular analyses based on amplification of the rDNA ITS region. Although we identified certain morphometric differences compared with the original description, the molecular data indicated that the ITS sequence obtained for the UEL 08 isolate is identical to the reference sequence of H. amazonensis (DQ665222) and presented 100% similarity. Thus, the findings of our morphological and molecular studies confirmed that the isolated nematode is H. amazonensis, which is the first time this species has been registered in Paraná. Study of the biological characteristics of H. amazonensis (UEL 08) revealed that the isolate has two distinct life cycles – one short (216 h) and the other long (288 h) – and produces two generations in both cycles. We observed that H. amazonensis (UEL 8) was pathogenic and virulent to the three evaluated hosts, although with different virulence against these hosts. The larvae of G. mellonella and Alphitobius diaperinus were more susceptible than adult Dichelops (Diacereus) melacanthus, with 100%, 85%, and 46% mortality, respectively. Furthermore, an in vivo production assay revealed a mean daily yield of 3.4 × 103 infective juveniles/g host larvae. Resumo Nematoides entomopatogênicos (NEP) das famílias Heterorhabditidae e Steinernematidae são amplamente utilizados no controle de insetos-pragas. No Brasil, os estudos relacionados a caracterização e identificação destes entomopatógenos são recentes e escassos. Nesse sentido, o objetivo deste estudo foi isolar NEP de amostras de solos coletadas em diferentes áreas no estado do Paraná, Brasil. Um isolado Heterorhabditis (UEL 08) detectado em amostra de solo em área de pastagem cultivada com braquiária, localizada em Londrina, Paraná, Brasil (23º34´311´´S, 050º58´298´´W), utilizando o método de “inseto-isca” com lagartas de Galleria mellonella. Para a identificação foram realizados estudos de morfometria e identificação molecular a partir da amplificação da região ITS. Algumas diferenças foram encontradas em termos de morfometria em comparação com a descrição original, entretanto, os dados moleculares demonstraram que a sequência obtida para o isolado UEL 08 é idêntica à sequência de referência de H. amazonensis (DQ665222), com a qual apresentou 100% de similaridade. Os estudos das características biológicas de H. amazonensis (UEL 08) revelaram que o isolado tem dois ciclos de vida distintos, um curto (216 h) e outro longo (288 h), sendo que ocorrem duas gerações em ambos os ciclos. O isolado UEL 08 H. amazonensis foi patogénico e virulento sobre os três hospedeiros avaliados. Notadamente, as larvas de G. mellonella e Alphitobius diaperinus foram consideradas mais susceptíveis do que os adultos do percevejo Dichelops (Diacereus) melacanthus, com percentagens de mortalidade de 100%, 85% e 46% de mortalidade, respectivamente. O ensaio de produção in vivo revelou um rendimento médio diário de 3,4 × 103 juvenis infectantes/g de larva hospedeira.

PSIFA – Pattern Search and Implicit Filtering Algorithm – is a derivative-free algorithm that has been designed for linearly constrained problems with noise in the objective function. It combines s...

This study details 13 novel polymorphic microsatellite loci in the armoured catfish Hypostomus ancistroides, and assesses their utility for population genetic studies. The analysis of 30 individuals revealed a total of 99 different alleles (ranging from two to 15 alleles per locus), with an average of 7·62 alleles per locus, with observed and expected heterozygosities ranging from 0·103 to 0·931 and from 0·102 to 0·906, respectively. One of the 13 loci showed significant deviations from Hardy-Weinberg equilibrium, probably due to the presence of null alleles, inferred from the excess of homozygotes.

Fourteen polymorphic microsatellite loci were isolated and characterized for the Neotropical cichlid Geophagus brasiliensis and tested on 30 individuals belonging to a single population. Among the 14 loci described, four showed potential presence of null alleles, inferred from the excess of homozygous genotypes, and three of these loci showed significant deviations from Hardy-Weinberg equilibrium. Fifty-nine different alleles were detected (ranging from two to eight alleles per locus), with estimates of observed and expected heterozygosity ranging from 0·167 to 0·700 and from 0·269 to 0·825. Cross-amplification of primers was successful in five other cichlid species.

Objetivou-se avaliar as características morfo-anatômicas de cinco genótipos de milho normais (F2, Lu16, F271, Lu5 e Lu6) e cinco bm3 (F2bm3, Lu16bm3, F271bm3, Lu5bm3 e Lu6bm3) com inferência à qualidade para silagem cultivados em Druelle-França, em parcelas de 150 m² durante o período de maio a setembro de 2002 (150 dias). Todas as avaliações foram realizadas no entrenó abaixo da espiga principal. O delineamento experimental utilizado foi o inteiramente casualizado com cinco repetições por tratamento. Os genótipos apresentaram diferenças significativas quanto aos aspectos anatômicos, sendo que todos os genótipos bm3 apresentaram menores quanti-dades de células lignificadas tanto na região medular (1,24) quanto na região do córtex (1,72). Observou-se correlação positiva (r= 0,70) entre a quantidade de células lignificadas da região medular e a porcentagem de região medular. Também houve correlação positiva (r= 0,67) e negativa (r= -0,67), entre a espessura da parede celular com a % de xilema e com a % de floema, respectivamente. Os resultados encontrados estão coerentes aos tipos de linhagens estudadas, pois as linhagens bm3 são caracterizadas por apresentarem menores proporções de lignina quando comparados com genótipos normais.

Few vaccines in history have induced such a dramatic decline in incidence over such a short period of time as the Haemophilus influenzae type b (Hib) conjugate. This vaccine was introduced in 1988 in the United States, but only in 1999 was Hib immunization introduced by the Brazilian Ministry of Health as part of the routine infant National Immunization Program. The authors analyzed 229 H. influenzae (Hi) isolates from Public Health Laboratories in three Brazilian states: Pernambuco (Northeast, N = 54), Santa Catarina (South, N = 19), and Rio de Janeiro (Southeast, N = 156). The isolates were collected from Brazilian children 0-10 years of age with meningitis and other infections from 1990 to 2003 and were part of the research collection of the National Institute of Quality Control in Health, FIOCRUZ. Bacterial strains were characterized by serotyping and biotyping. During the pre-vaccination period the prevalence infection due to Hib was of 165 isolates and only 2 non-b Hi among all the notified meningitis infections caused by Hi. Our results showed a significant decrease in the prevalence of Hib meningitis from 165 to 33 isolates after 1999. However, during the post-vaccination period of 2001-2003 we observed an increase in the number of non-b Hi isolates: only 2 non-b strains isolated from 1990 to 1999 and 29 from 1999 to 2003. Based on the present data, the authors emphasize the need for more sensitive epidemiological and bacteriological studies aiming the improvement of the available Hib vaccine, in order to protect the susceptible population to infections due to other serological types of Hi and the reevaluation of immunization schedules used by the National Immunization Program.

En un Inceptisol húmedos del campo experimental de la Amazonia baja (2°23? de latitud sur y 54°20? de longitud oeste, municipio de Monte Alegre, Pará, Brasil) de la Empresa Brasileira de Pesquisa Agropecuária (Embrapa-Amazonia Oriental), en julio de 2003 (final del período lluvioso), septiembre de 2003 (período seco) y enero de 2004 (comienzo del período lluvioso) se determinaron los contenido de proteína cruda (PC), estracto etereo (EE) y minerales en el forraje de Paspalum repens (Perimembeca) e Paspalum fasciculatum (Mori) procedentes de la zona de varzea. Se utilizó un factorial de dos (especies nativas de forraje) y tres épocas de crecimiento (final y comienzo del periodo lluviosa y época seca). Se encontraron diferencias (P < 0.05) para el contenido de PC de las especies, siendo más alto en Perimembeca (12.06%) que en Mori (6.65). El contenido de P en ambas gramíneas fue bajo. El contenido de Cu en la gramínea Mori fue adecuado en tanto épocas secas como húmedas. Los contenidos de Ca, K y Fe fueron bajos e influenciados por la época.