670 research outputs found
The billiard inside an ellipse deformed by the curvature flow
The billiard dynamics inside an ellipse is integrable. It has zero
topological entropy, four separatrices in the phase space, and a continuous
family of convex caustics: the confocal ellipses. We prove that the curvature
flow destroys the integrability, increases the topological entropy, splits the
separatrices in a transverse way, and breaks all resonant convex caustics.Comment: 13 pages, 1 figur
Draft of Cheyenne & Arapahoe Report
https://digitalcommons.assumption.edu/mallet-manuscripts/1030/thumbnail.jp
Guidelines for the diagnosis, treatment and clinical monitoring of patients with juvenile and adult Pompe disease
Pompe disease (PD) is a potentially lethal illness involving irreversible muscle damage resulting from glycogen storage in muscle fiber and activation of autophagic pathways. A promising therapeutic perspective for PD is enzyme replacement therapy (ERT) with the human recombinant enzyme acid alpha-glucosidase (Myozyme (R)). The need to organize a diagnostic flowchart, systematize clinical follow-up, and establish new therapeutic recommendations has become vital, as ERT ensures greater patient longevity. A task force of experienced clinicians outlined a protocol for diagnosis, monitoring, treatment, genetic counseling, and rehabilitation for PD patients. The study was conducted under the coordination of REBREPOM, the Brazilian Network for Studies of PD. The meeting of these experts took place in October 2013, at L'Hotel Port Bay in Sao Paulo, Brazil. In August 2014, the text was reassessed and updated. Given the rarity of PD and limited high-impact publications, experts submitted their views.Inst Fernandes Figueira FIOCRUZ, Dept Med Genet, Rio De Janeiro, RJ, BrazilUniv Fed Fluminense, Dept Neurol & NeuroUPC, BR-22031171 Rio De Janeiro, RJ, BrazilUniv Fed Sao Paulo, Dept Neurol, Sao Paulo, SP, BrazilUniv Fed Rio Grande do Norte, Dept Neurol, Caiaco, RN, BrazilClin Marrone, Porto Alegre, RS, BrazilUniv Cuiaba, Dept Neurol, Cuiaba, MT, BrazilUniv Sao Paulo, Dept Neurociencias, BR-14049 Ribeirao Preto, SP, BrazilHosp Base Dist Fed, Serv Neurol, Brasilia, DF, BrazilUniv Fed Parana, Serv Doencas Neuromusculares, BR-80060000 Curitiba, Parana, BrazilUniv Fed Sao Paulo, Dept Neurol, Sao Paulo, SP, BrazilWeb of Scienc
Limitations of selective deltamethrin application for triatomine control in central coastal Ecuador
<p>Abstract</p> <p>Background</p> <p>This year-long study evaluated the effectiveness of a strategy involving selective deltamethrin spraying and community education for control of Chagas disease vectors in domestic units located in rural communities of coastal Ecuador.</p> <p>Results</p> <p>Surveys for triatomines revealed peridomestic infestation with <it>Rhodnius ecuadoriensis </it>and <it>Panstrongylus howardi</it>, with infestation indices remaining high during the study (13%, 17%, and 10%, at initial, 6-month, and 12-month visits, respectively), which indicates a limitation of this strategy for triatomine population control. Infestation was found 6 and 12 months after spraying with deltamethrin. In addition, a large number of previously vector-free domestic units also were found infested at the 6- and 12-month surveys, which indicates new infestations by sylvatic triatomines. The predominance of young nymphs and adults suggests new infestation events, likely from sylvatic foci. In addition, infection with <it>Trypanosoma cruzi </it>was found in 65%, 21% and 29% at initial, 6-month and 12-month visits, respectively. All parasites isolated (n = 20) were identified as TcI.</p> <p>Conclusion</p> <p>New vector control strategies need to be devised and evaluated for reduction of <it>T. cruzi </it>transmission in this region.</p
Probing the SELEX Process with Next-Generation Sequencing
Background SELEX is an iterative process in which highly diverse synthetic nucleic acid libraries are selected over many rounds to finally identify aptamers with desired properties. However, little is understood as how binders are enriched during the selection course. Next-generation sequencing offers the opportunity to open the black box and observe a large part of the population dynamics during the selection process. Methodology We have performed a semi-automated SELEX procedure on the model target streptavidin starting with a synthetic DNA oligonucleotide library and compared results obtained by the conventional analysis via cloning and Sanger sequencing with next-generation sequencing. In order to follow the population dynamics during the selection, pools from all selection rounds were barcoded and sequenced in parallel. Conclusions High affinity aptamers can be readily identified simply by copy number enrichment in the first selection rounds. Based on our results, we suggest a new selection scheme that avoids a high number of iterative selection rounds while reducing time, PCR bias, and artifacts
Caracterização molecular do Cão Barbado da Terceira
Dissertação de Mestrado em Engenharia Zootécnica.Neste trabalho analisaram-se 257 animais da raça Cão Barbado da Terceira sendo caracterizados geneticamente, por doze microssatélites identificando-se um total de 79 alelos. A variabilidade genética foi estimada através das frequências alélicas, diversidade genética, heterozigocidade esperada e observada, probabilidade de identidade e verificação do equilíbrio de Hardy-Weinberg. Analisou-se as distâncias genéticas entre grupos pré-definidos consoante o ano de nascimento. Realizaram-se testes de paternidade comparando com os dados cedidos pelos criadores dos animais em questão, com bons resultados confirmando-se a compatibilidade com os progenitores na maioria dos casos. A população continua a manter variabilidade genética suficiente para não sofrer um processo de inbreeding, contudo deve ser dada atenção aos reprodutores a serem utilizados no futuro de forma a se conseguir uma maior heterozigocidade na raça para que haja uma evolução positiva da mesma. Desta forma os objectivos deste trabalho foram conseguidos, sendo este tipo de marcadores moleculares suficientemente informativos para esta caracterização.ABSTRACT: In this study 257 animals from the Cão Barbado da Terceira breed were analyzed, which were genetically characterized with twelve microsatellites, with a total of 79 alleles identified. The genetic variability was estimated through the allelic frequencies, genetic diversity, expected and observed heterozygosity, identity probability and verification of the Hardy-Weinberg equilibrium. There was also the analysis of the genetic distances between groups predefined according to the year of birth, as well as paternity tests by the comparison with the data provided by the breeders. Good results were obtained and the compatibility with the parents was confirmed in most cases. The population still maintains enough genetic variability in order not to undergo inbreeding however one should pay attention to the breeders to be used in the future, in a way to obtain a higher heterozygosity so there is a positive evolution of the breed. Therefore the aims of this study were achieved, and this type of molecular markers was sufficiently informative for this characterization
Phylogeographic pattern and extensive mitochondrial DNA divergence disclose a species complex within the Chagas disease vector Triatoma dimidiata.
ABSTARCT: Previous studies have shown that "bioequivalent" generic products of vancomycin are less effective in vivo against Staphylococcus aureus than the innovator compound. Considering that suboptimal bactericidal effect has been associated with emergence of resistance, we aimed to assess in vivo the impact of exposure to innovator and generic products of vancomycin on S. aureus susceptibility. A clinical methicillin-resistant S. aureus (MRSA) strain from a liver transplant patient with persistent bacteremia was used for which MIC, minimum bactericidal concentration (MBC), and autolytic properties were determined. Susceptibility was also assessed by determining a population analysis profile (PAP) with vancomycin concentrations from 0 to 5 mg/liter. ICR neutropenic mice were inoculated in each thigh with ∼7.0 log(10) CFU. Treatment with the different vancomycin products (innovator and three generics; 1,200 mg/kg of body weight/day every 3 h) started 2 h later while the control group received sterile saline. After 24 h, mice were euthanized, and the thigh homogenates were plated. Recovered colonies were reinoculated to new groups of animals, and the exposure-recovery process was repeated until 12 cycles were completed. The evolution of resistance was assessed by PAP after cycles 5, 10, 11, and 12. The initial isolate displayed reduced autolysis and higher resistance frequencies than S. aureus ATCC 29213 but without vancomycin-intermediate S. aureus (VISA) subpopulations. After 12 cycles, innovator vancomycin had significantly reduced resistant subpopulations at 1, 2, and 3 mg/liter, while the generic products had enriched them progressively by orders of magnitude. The great capacity of generic vancomycin to select for less susceptible organisms raises concerns about the role of therapeutic inequivalence of any antimicrobial on the epidemiology of resistance worldwide
Distribution and abundance of Pleuronectiformes larvae off Southeastern Brazil
The objective of this study was the description of the composition, abundance and density in horizontal and vertical distribution of Pleuronectiformes larvae on the southeastern Brazilian continental shelf. The samples were collected with bongo nets and a Multi Plankton Sampler (MPS), both in summer and winter 2002. A total of 352 flatfishes larvae were collected in summer and 343 in winter, representing three families and a total of 13 taxa: Paralichthyidae (Citharichthys cornutus, C. spilopterus, Citharichthys sp., Cyclopsetta chittendeni, Syacium spp., Etropus spp. and Paralichthys spp.), Bothidae (Bothus ocellatus and Monolene antillarum) and Cynoglossidae (Symphurus trewavasae, S. jenynsi, S. plagusia and S. ginsburgi). The most abundant taxa were Etropus spp., Syacium spp. and Bothus ocellatus. Etropus spp. occurred mainly as far out as the 200 m isobath and Syacium spp. from 100 m. B. ocellatus was present mainly in the oceanic zone between Ubatuba and Rio de Janeiro as from the 200 m isobath. The greatest average densities of these species occurred in the strata from 0 to 20 m depth in summer and between 20 and 40 m in winter
Role of sesquiterpenes in biogenic new particle formation
Biogenic vapors form new particles in the atmosphere, affecting global climate. The contributions of monoterpenes and isoprene to new particle formation (NPF) have been extensively studied. However, sesquiterpenes have received little attention despite a potentially important role due to their high molecular weight. Via chamber experiments performed under atmospheric conditions, we report biogenic NPF resulting from the oxidation of pure mixtures of β-caryophyllene, α-pinene, and isoprene, which produces oxygenated compounds over a wide range of volatilities. We find that a class of vapors termed ultralow-volatility organic compounds (ULVOCs) are highly efficient nucleators and quantitatively determine NPF efficiency. When compared with a mixture of isoprene and monoterpene alone, adding only 2% sesquiterpene increases the ULVOC yield and doubles the formation rate. Thus, sesquiterpene emissions need to be included in assessments of global aerosol concentrations in pristine climates where biogenic NPF is expected to be a major source of cloud condensation nuclei
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