2,440 research outputs found
Sharp gene pool transition in a population affected by phenotype-based selective hunting
We use a microscopic model of population dynamics, a modified version of the
well known Penna model, to study some aspects of microevolution. This research
is motivated by recent reports on the effect of selective hunting on the gene
pool of bighorn sheep living in the Ram Mountain region, in Canada. Our model
finds a sharp transition in the structure of the gene pool as some threshold
for the number of animals hunted is reached.Comment: 5 pages, 4 figure
Partial Papillary Muscle Rupture after Myocardial Infarction and Early Severe Obstructive Bioprosthetic Valve Thrombosis: an Unusual Combination
Mechanical complications after myocardial infarction (MI) have become uncommon since the introduction of primary angioplasty. They can lead to a rapid clinical deterioration and a fatal outcome, with patient’s survival being dependent on their prompt recognition and intervention. We describe a case of two rare mechanical complications: a partial papillary muscle rupture after MI, followed by an early severe obstructive thrombosis of the implanted bioprosthetic valve.info:eu-repo/semantics/publishedVersio
Delivery of the 135kb human frataxin genomic DNA locus gives rise to different frataxin isoforms
© 2015 Elsevier Inc. Friedreich's ataxia (FRDA) is the most common form of hereditary ataxia caused by recessive mutations in the FXN gene. Recent results have indicated the presence of different frataxin isoforms due to alternative gene expression mechanisms. Our previous studies demonstrated the advantages of using high-capacity herpes simplex virus type 1 (HSV-1) amplicon vectors containing the entire FXN genomic locus (iBAC-FXN) as a gene-delivery vehicle capable of ensuring physiologically-regulated and long-term persistence. Here we describe how expression from the 135. kb human FXN genomic locus produces the three frataxin isoforms both in cultured neuronal cells and also in vivo. Moreover, we also observed the correct expression of these frataxin isoforms in patient-derived cells after delivery of the iBAC-. FXN. These results lend further support to the potential use of HSV-1 vectors containing entire genomic loci whose expression is mediated by complex transcriptional and posttranscriptional mechanisms for gene therapy applications.Spanish National Research Plan (SAF 2012-38042) and the Autonomous Government of Madrid (S2010/BMD-2331). The Center for Biomedical Research on Rare Diseases (“Centro de Investigación Biomédica en Red sobre Enfermedades Raras”, CIBERER) is an initiative supported by the “Instituto de Salud Carlos III”.Peer Reviewe
Characterization of the Use and Occupation of Soil on Rural Properties Using Remotely Piloted Aircraft Systems - RPAS
The use of remotely piloted aircraft systems allows for practicality in the collection and monitoring of study areas or in the development of rehabilitation projects for degraded areas. As such, this technology is gaining space as an alternative for applications in studies and surveys of several areas. This work is justified by the demand for projects and the search for practical alternatives that will enable the framing of rural properties according to the new Brazilian Forestry Code (Codígo Florestal Brasileiro) and its environmental recovery plans (Plano de Recuperação Ambiental). The objective of this study is therefore to evaluate the use of a Remotely Piloted Aircraft System in the monitoring of a rural property, seeking to include it in the framework of the Brazilian Forestry Code. To accomplish this work, information samples were taken in an area of 30.19 ha of a rural property with the use of a Remotely Piloted Aircraft System - RPAS. After the data collection, the images were treated using the QGis software and through the generation of an ortho-mosaic, which enabled the data to be analyzed and interpreted. With the interpretation of land use and occupation data and with the generation of maps of land use and occupation, a diagnosis of the current situation of the area can be obtained. In a second phase, maps were created to include the property in the current legislative framework, seeking its regularization. After the completion of this work, the conclusion can be drawn that the use of a Remotely Piloted Aircraft System - RPAS is viable and enables the monitoring of rural areas with efficiency and speed
Atividades alelopática de extratos hidroalcoólicos de diferentes frações de Acacia mangium (Leguminosae).
Spectral properties on a circle with a singularity
We investigate the spectral and symmetry properties of a quantum particle
moving on a circle with a pointlike singularity (or point interaction). We find
that, within the U(2) family of the quantum mechanically allowed distinct
singularities, a U(1) equivalence (of duality-type) exists, and accordingly the
space of distinct spectra is U(1) x [SU(2)/U(1)], topologically a filled torus.
We explore the relationship of special subfamilies of the U(2) family to
corresponding symmetries, and identify the singularities that admit an N = 2
supersymmetry. Subfamilies that are distinguished in the spectral properties or
the WKB exactness are also pointed out. The spectral and symmetry properties
are also studied in the context of the circle with two singularities, which
provides a useful scheme to discuss the symmetry properties on a general basis.Comment: TeX, 26 pages. v2: one reference added and two update
Efeitos alelopáticos de extratos hidroalcoólicos de Senna alata sobre três espécies de áreas de pastagem.
Micromegas operation in high pressure xenon: charge and scintillation readout
The operational characteristics of a Micromegas operating in pure xenon at
the pressure range of 1 to 10 bar are investigated. The maximum charge gain
achieved in each pressure is approximately constant, around 4x10^2, for xenon
pressures up to 5 bar and decreasing slowly above this pressure down to values
somewhat above 10^2 at 10 bar. The MM presents the highest gains for xenon
pressures above 4 bar, when compared to other micropattern gaseous multipliers.
The lowest energy resolution obtained for X-rays of 22.1 keV exhibits a steady
increase with pressure, from 12% at 1bar to about 32% at 10 bar. The effective
scintillation yield, defined as the number of photons exiting through the MM
mesh holes per primary electron produced in the conversion region was
calculated. This yield is about 2x10^2 photons per primary electron at 1 bar,
increasing to about 6x10^2 at 5 bar and, then, decreasing again to 2x10^2 at 10
bar. The readout of this scintillation by a suitable photosensor will result in
higher gains but with increased statistical fluctuations.Comment: 22 pages, 11 figure
Weevil associated to gummosis in oil palm (Elaeis guineensis Jacq.) in Brazil.
In commercial plantations of oil palm in Nazare municipality, state of Bahia, Brazil, the association of Rhinostomus barbirostris Fabricius and Ceratocystis paradoxa (Dade) C. Moreau in high number of oil palm trees showing stem bleeding symptoms was observed. The pathogen was isolated from tissues of diseased oil palm plants. To our knowledge this is the first report on the contribution of R. barbirostris to increase the severity of stem bleeding disease caused by C. paradoxa in oil palm. Control measures are suggested
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