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VPI Processes and Resin Evaluations for CPA Electrical Windings
High energy density requirements for fieldable electric gun applications has led to the air-core compensated pulsed alternator (CPA) or compulsator as the generator of choice to provide pulse power. The air-core nature of the machines combined with ambitious power density requirements has led to the minimizing of metallic supporting structures which places additional structural requirements on the electrical windings within the generators.Center for Electromechanic
Cytogenetically distinguishable sympatric and allopatric populations of the mosquito Anopheles albitarsis
Salivary gland chromosome slides of Anopheles albitarsis from Brasil, Colombia and Venezuela indicate that at least three chromosomally differentiated populations of this species exist in this area. The B1 population from Brasil contains one heterozygous inversion in the X and two in the autosomes. Population B2, sympatric with B1 in Brasil, differs from it by two inversions in the X and ten in the autosomes. Population C in Colombia and Venezuela is closer to B1, from which it differs by three inversions in chromosome 2 and three in chromosome 3. Each population, B1, B2 and C may be distinguished with about 98% certainty using the banding patterns of the X chromosomes. Most of the remaining individuals may be identified using a combination of the X and autosomal paracentric inversions. The scarcity of shared inversions argues for little if any natural hybridization among these populations. A standard salivary gland chromosome map, based on the B1 populations, is presented.Estudos citológicos utilizando cromossomos politênicos das glândulas salivares de Anopheles albitarsis, coletados no Brasil, Colômbia e Venezuela indicam que existem pelo menos 3 populações, que são diferentes cromossomicamente. Todas as três podem ser diferenciadas usando somente o cromossomo X. A população B1 do Brasil tem uma inversão heterozigota no cromossomo X e duas nos autossomos. A população B2, simpátrica com a B1, no Brasil, varia daquela por duas inversões no X e dez nos autossomos. A terceira população C, a qual se encontra na Colômbia e Venezuela, mostra mais proximidade a B1, da qual ela varia por três inversões no cromossomo 2 e três inversões no cromossomo 3. Cada população, B1, B2 e C pode ser identificada com 98 por cento de certeza usando a seqüência das bandas do cromossomo X. A escassez das inversões comuns indica uma baixa taxa de hibridismo na natureza entre estas populações. É apresentado um mapa dos cromossomos de glândulas salivares de larvas da população B1 para ser considerado como padrão para esta espécie
Prevalence and Timing of Postpartum Glucose Testing and Sustained Glucose Dysregulation After Gestational Diabetes Mellitus
Narrow genetic base in forest restoration with holm oak (Quercus ilex L.) in Sicily
In order to empirically assess the effect of actual seed sampling strategy on
genetic diversity of holm oak (Quercus ilex) forestations in Sicily, we have
analysed the genetic composition of two seedling lots (nursery stock and
plantation) and their known natural seed origin stand by means of six nuclear
microsatellite loci. Significant reduction in genetic diversity and significant
difference in genetic composition of the seedling lots compared to the seed
origin stand were detected. The female and the total effective number of
parents were quantified by means of maternity assignment of seedlings and
temporal changes in allele frequencies. Extremely low effective maternity
numbers were estimated (Nfe 2-4) and estimates accounting for both
seed and pollen donors gave also low values (Ne 35-50). These values
can be explained by an inappropriate forestry seed harvest strategy limited to
a small number of spatially close trees
Microalbuminuria, Preeclampsia, and Preterm Delivery in Pregnant Women With Type 1 Diabetes: Results from a nationwide Danish study
Inversions are bigger on the X chromosome
In many insects, X‐linked inversions fix at a higher rate and are much less polymorphic
than autosomal inversions. Here, we report that in Drosophila, X‐linked inversions
also capture 67% more genes. We estimated the number of genes captured
through an approximate Bayesian computational analysis of gene orders in nine species
of Drosophila. X‐linked inversions fixed with a significantly larger gene content.
Further, X‐linked inversions of intermediate size enjoy highest fixation rate, while
the fixation rate of autosomal inversions decreases with size. A less detailed analysis
in Anopheles suggests a similar pattern holds in mosquitoes. We develop a population
genetic model that assumes the fitness effects of inversions scale with the
number of genes captured. We show that the same conditions that lead to a higher
fixation rate also produce a larger size for inversions on the X
Anopheles aquasalis Eggs from Two Venezuelan Localities Compared by Scanning Electron Microscopy
Anopheles darlingi polytene chromosomes: revised maps including newly described inversions and evidence for population structure in Manaus
Salivary gland polytene chromosomes of 4th instar Anopheles darlingi Root were examined from multiple locations in the Brazilian Amazon. Minor modifications were made to existing polytene photomaps. These included changes to the breakpoint positions of several previously described paracentric inversions and descriptions of four new paracentric inversions, two on the right arm of chromosome 3 and two on the left arm of chromosome 3 that were found in multiple locations. A total of 18 inversions on the X (n = 1) chromosome, chromosome 2 (n = 7) and 3 (n = 11) were scored for 83 individuals from Manaus, Macapá and Porto Velho municipalities. The frequency of 2Ra inversion karyotypes in Manaus shows significant deficiency of heterozygotes (p < 0.0009). No significant linkage disequilibrium was found between inversions on chromosome 2 and 3. We hypothesize that at least two sympatric subpopulations exist within the An. darlingi population at Manaus based on inversion frequencies
Systematic notes on Anopheles Meigen (Diptera: Culicidae) species in the state of Amapá, Brazil
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