21 resultados para found objects

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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Most museums, libraries, and archives throughout the world have to deal with paper damaged by iron gall ink. For more than a decade international research has been devoted to the topic in an attempt to provide practical treatments for objects and formulate guidelines for the preservation of iron gall ink collections. A working group of conservators in South and Central America and the Caribbean have developed a program to disseminate research findings, collect data about the condition of iron gall ink collections in their countries and identify imminent training needs. The goal of this project is to combine the latest research with existing and acceptable conservation practices and share information about risk management, proper housing, examination and treatment of iron gall ink inscribed artefacts-at risk. Communications among colleagues were established to learn more about the current resources available in collections from various countries.

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Observations of cosmic rays arrival directions made with the Pierre Auger Observatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with objects drawn from the Veron-Cetty Veron catalog. In this paper we report on the use of three catalog independent methods to search for anisotropy. The 2pt-L, 2pt+ and 3pt methods, each giving a different measure of self-clustering in arrival directions, were tested on mock cosmic ray data sets to study the impacts of sample size and magnetic smearing on their results, accounting for both angular and energy resolutions. If the sources of UHECRs follow the same large scale structure as ordinary galaxies in the local Universe and if UHECRs are deflected no more than a few degrees, a study of mock maps suggests that these three method can efficiently respond to the resulting anisotropy with a P-value = 1.0% or smaller with data sets as few as 100 events. using data taken from January 1, 2004 to July 31, 2010 we examined the 20, 30, ... , 110 highest energy events with a corresponding minimum energy threshold of about 49.3 EeV. The minimum P-values found were 13.5% using the 2pt-L method, 1.0% using the 2pt+ method and 1.1% using the 3pt method for the highest 100 energy events. In view of the multiple (correlated) scans performed on the data set, these catalog-independent methods do not yield strong evidence of anisotropy in the highest energy cosmic rays.

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We describe the genetic transformation of the mycelial tissue of Diaporthe phaseolorum, an endophytic fungus isolated from the mangrove species Laguncularia racemosa, using Agrobacterium tumefaciens-mediated transformation (ATMT). ATMT uses both the hygromycin B resistant (hph) gene and green fluorescent protein as the selection agents. The T-DNA integration into the fungal genome was assessed by both PCR and Southern blotting. All transformants examined were mitotically stable. An analysis of the T-DNA flanking sequences by thermal asymmetric interlaced PCR (TAIL-PCR) demonstrated that the disrupted genes in the transformants had similarities with conserved domains in proteins involved in antibiotic biosynthesis pathways. A library of 520 transformants was generated, and 31 of these transformants had no antibiotic activity against Staphylococcus aureus, an important human pathogen. The protocol described here, using ATMT in D. phaseolorum, will be useful for the identification and analysis of fungal genes controlling pathogenicity and antibiotic pathways. Moreover, this protocol may be used as a reference for other species in the Diaporthe genus. This is the first report to describe Agrobacterium-mediated transformation of D. phaseolorum as a tool for insertional mutagenesis.

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Discusses the technological changes that affects learning organizations as well as the human, technical, legal and sustainable aspects regarding learning objects repositories creation, maintenance and use. It presents concepts of information objects and learning objects, the functional requirements needed to their storage at Learning Management Systems. The role of Metadata is reviewed concerning learning objects creation and retrieval, followed by considerations about learning object repositories models, community participation/collaborative strategies and potential derived metrics/indicators. As a result of this desktop research, it can be said that not only technical competencies are critical to any learning objects repository implementation, but it urges that an engaged community of interest be establish as a key to support a learning object repository project. On that matter, researchers are applying Activity Theory (Vygostky, Luria y Leontiev) in order to seek joint perceptions and actions involving learning objects repository users, curators and managers, perceived as critical assets to a successful proposal.

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Implementing precise techniques in routine diagnosis of chronic granulomatous disease (CGD), which expedite the screening of molecular defects, may be critical for a quick assumption of patient prognosis. This study compared the efficacy of single-strand conformation polymorphism analysis (SSCP) and high-performance liquid chromatography under partially denaturing conditions (dHPLC) for screening mutations in CGD patients. We selected 10 male CGD patients with a clinical history of severe recurrent infections and abnormal respiratory burst function. gDNA, mRNA and cDNA samples were prepared by standard methods. CYBB exons were amplified by PCR and screened by SSCP or dHPLC. Abnormal DNA fragments were sequenced to reveal the nature of the mutations. The SSCP and dHPLC methods showed DNA abnormalities, respectively, in 55% and 100% of the cases. Sequencing of the abnormal DNA samples confirmed mutations in all cases. Four novel mutations in CYBB were identified which were picked up only by the dHPLC screening (c.904 insC, c.141+5 g>t, c.553 T>C, and c.665 A>T). This work highlights the relevance of dHPLC, a sensitive, fast, reliable and cost-effective method for screening mutations in CGD, which in combination with functional assays assessing the phagocyte respiratory burst will contribute to expedite the definitive diagnosis of X-linked CGD, direct treatment, genetic counselling and to have a clear assumption of the prognosis. This strategy is especially suitable for developing countries.

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Animal cruelty is defined as a deliberate action that causes pain and suffering to an animal. In Brazil, legislation known as the Environmental Crimes Law states that cruelty toward all animal species is criminal in nature. From 644 domestic cats necropsied between January 1998 and December 2009, 191 (29.66%) presented lesions highly suggestive of animal cruelty. The main necroscopic finding was exogenous carbamate poisoning (75.39%) followed by blunt-force trauma (21.99%). Cats from 7 months to 2 years of age were the most affected (50.79%). In Brazil, violence is a public health problem and there is a high prevalence of domestic violence. Therefore, even if laws provide for animal welfare and protection, animals are common targets for violent acts. Within a context of social violence, cruelty toward animals is an important parameter to be considered, and the non-accidental lesions that were found are evidence of malicious actions.

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We have searched for young star-forming regions around the merger remnant NGC 2782. By using Galaxy Evolution Explorer far-ultraviolet and near-ultraviolet imaging and H i data we found seven ultraviolet sources, located at distances greater than 26 kpc from the centre of NGC 2782, and coinciding with its western H i tidal tail. These regions were resolved in several smaller systems when Gemini/Gemini multi-object spectrograph (GMOS) r-band images were used. We compared the observed colours to stellar population synthesis models and found that these objects have ages of similar to 1 to 11 Myr and masses ranging from 103.9 to 104.6 M circle dot. By using Gemini/GMOS spectroscopic data we confirm memberships and derive high metallicities for three of the young regions in the tail (12+log(O/H) = 8.74 +/- 0.20, 8.81 +/- 0.20 and 8.78 +/- 0.20). These metallicities are similar to the value presented by the nuclear region of NGC 2782 and also similar to the value presented for an object located close to the main body of NGC 2782. The high metallicities measured for the star-forming regions in the gaseous tidal tail of NGC 2782 could be explained if they were formed out of highly enriched gas which was once expelled from the centre of the merging galaxies when the system collided. An additional possibility is that the tail has been a nursery of a few generations of young stellar systems which ultimately polluted this medium with metals, further enriching the already pre-enriched gas ejected to the tail when the galaxies collided.

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We describe a case of retinoblastoma with an atypical presentation and previously unreported cytogenetic aberrations. A 19-month-old girl with left intraocular retinoblastoma was treated with enucleation and chemotherapy. The disease showed aggressive evolution within a short period between diagnosis and relapse. Eight months after diagnosis, a new large tumor was present in the orbit of the right eye, with diffuse bone pain, pancytopenia and diffuse infiltration into the bone marrow and the central nervous system. The child did not respond to treatment and died. Cytogenetic studies made with G-banding, FISH and SKY analysis showed chromosomal aberrations commonly associated with retinoblastoma, including del(13q), i(6+1, and monosomy 16, along with others that had not been reported previously, including dup(5q), dic(15;22) and add(14q). The new chromosomal aberrations may be related to the aggressiveness of the disease in this case.

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Southern Brazil is considered an area of low Hepatitis B endemicity, but some areas of higher endemicity have been described in the Southwest of Parana and Santa Catarina states. The aim of this study was to evaluate viral genotypes circulating throughout Parana state. PCR amplification and partial sequencing of the S gene was carried out in 228 samples from HBsAg positive candidate blood donors. Samples have been collected in seven different counties (Cascavel, Curitiba, Foz do Iguacu, Francisco Beltrao, Matinga Londrina and Paranagua). The most common HBV genotype in Parana state was D (82.9%; 189/228), followed by A (14.1%; 32/228). Genotypes F (1.3%; 3/228), C (1.3%; 3/228) and H (0.4%; 1/228) were also found. Distribution of genotypes was different in the studied counties, but genotype D was the most frequent in all of them. In Francisco Beltrao, all studied samples belonged to genotype D. The high prevalence of HBV genotype Din South of Brazil is explained by the intense migration of settlers from Europeans countries. Subgenotypes A1 and A2 were identified circulating in all cities where HBV/A was found. As observed in other areas of Brazil, HBV/A1 is more frequent than the HBV/A2 in Parana state and its presence was significantly larger in black and mulatto individuals. Genotype C was found only in individuals with Asian ancestry from Londrina and Maringa. Most HBV/F sequences identified in this study were classified as subgenotype F2a that was previously described in Brazil. The sole case of subgenotype F4 was from Foz do Iguacu city, near to Northern Argentina, where F4 is highly prevalent. The single genotype H sample was from Curitiba. This is the first case of this genotype described in Brazil. Further studies should be carried out to determine if more genotype H samples can be found in other populations from Brazil. (C) 2012 Elsevier B.V. All rights reserved.

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Aims. Our goal is to study the circumstellar environment associated with each component of the wide intermediate-mass pre-main sequence binary system PDS 144 using broadband polarimetry. Methods. We present near-infrared (NIR) linear polarimetric observations of PDS 144 gathered with the IAGPOL imaging polarimeter along with the CamIV infrared camera at the Observatorio do Pico dos Dias (OPD). In addition, we re-analyzed OPD archive optical polarization to separate the binary and estimate the interstellar polarization using foreground stars. Results. After discounting the interstellar component, we found that both stars of the binary system are intrinsically polarized. The polarization vectors at optical and NIR bands of both components are aligned with the local magnetic field and the jet axis. These findings indicate an interplay between the interstellar magnetic field and the formation of the binary system. We also found that the PDS 144N is less polarized than its southern companion in the optical. However, in the NIR PDS 144N is more polarized. Our polarization data can only be explained by high inclinations (i greater than or similar to 80 degrees) for the disks of both members. In particular, comparisons of our NIR data with young stellar objects disk models suggest predominantly small grains in the circumstellar environment of PDS 144N. In spite of the different grain types in each component, the infrared spectral indexes indicate a coeval system. We also found evidence of coplanarity between the disks.

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Let D be a division ring with center k, and let D-dagger be its multiplicative group. We investigate the existence of free groups in D-dagger, and free algebras and free group algebras in D. We also go through the case when D has an involution * and consider the existence of free symmetric and unitary pairs in D-dagger.

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Context. Detections of molecular lines, mainly from H-2 and CO, reveal molecular material in planetary nebulae. Observations of a variety of molecules suggest that the molecular composition in these objects differs from that found in interstellar clouds or in circumstellar envelopes. The success of the models, which are mostly devoted to explain molecular densities in specific planetary nebulae, is still partial however. Aims. The present study aims at identifying the influence of stellar and nebular properties on the molecular composition of planetary nebulae by means of chemical models. A comparison of theoretical results with those derived from the observations may provide clues to the conditions that favor the presence of a particular molecule. Methods. A self-consistent photoionization numerical code was adapted to simulate cold molecular regions beyond the ionized zone. The code was used to obtain a grid of models and the resulting column densities are compared with those inferred from observations. Results. Our models show that the inclusion of an incident flux of X-rays is required to explain the molecular composition derived for planetary nebulae. We also obtain a more accurate relation for the N(CO)/N(H-2) ratio in these objects. Molecular masses obtained by previous works in the literature were then recalculated, showing that these masses can be underestimated by up to three orders of magnitude. We conclude that the problem of the missing mass in planetary nebulae can be solved by a more accurate calculation of the molecular mass.

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Occurrence of Zoophthora radicans infecting nymphs and adults of Thaumastocoris peregrinus Carpintero and Dellape, 2006 is reported in Brazil. This is a new record of host for this fungal species and the first fungal pathogen associated with this pest worldwide. Infection of Z. radicans on T. peregrinus populations on commercial Eucalyptus plantation (Eucalyptus spp.) reached up to 100%, and low insect densities were associated with high levels of fungal infection in three out of seven plots. This pathogen seems to be virulent against T. peregrinus and may play an important role in population regulations of this invasive pest through naturally induced epizootics. (c) 2012 Elsevier Inc. All rights reserved.

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Aims. Several embedded clusters are found in the Galaxy. Depending on the formation scenario, most of them can evolve to unbounded groups that are dissolved within 10 Myr to 20 Myr. A systematic study of young stellar clusters that show distinct characteristics provides interesting information on the evolutionary phases during the pre-main sequence. To identify and to understand these phases we performed a comparative study of 21 young stellar clusters. Methods. Near-infrared data from 2MASS were used to determine the structural and fundamental parameters based on surface stellar density maps, radial density profile, and colour-magnitude diagrams. The cluster members were selected according to their membership probability, which is based on the statistical comparison with the cluster proper motion. Additional members were selected on the basis of a decontamination procedure that was adopted to distinguish field stars found in the direction of the cluster area. Results. We obtained age and mass distributions by comparing pre-main sequence models with the position of cluster members in the colour-magnitude diagram. The mean age of our sample is similar to 5 Myr, where 57% of the objects is found in the 4-10 Myr range of age, while 43% is <4 Myr old. Their low E(B - V) indicate that the members are not suffering high extinction (AV <1 mag), which means they are more likely young stellar groups than embedded clusters. Relations between structural and fundamental parameters were used to verify differences and similarities that could be found among the clusters. The parameters of most of the objects show the same trends or correlations. Comparisons with other young clusters show similar relations among mass, radius, and density. Our sample tends to have larger radius and lower volumetric density than embedded clusters. These differences are compatible with the mean age of our sample, which we consider intermediate between the embedded and the exposed phases of the stellar clusters evolution.

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Background: Most investigations regarding the First Americans have primarily focused on four themes: when the New World was settled by humans; where they came from; how many migrations or colonization pulses from elsewhere were involved in the process; and what kinds of subsistence patterns and material culture they developed during the first millennia of colonization. Little is known, however, about the symbolic world of the first humans who settled the New World, because artistic manifestations either as rock-art, ornaments, and portable art objects dated to the Pleistocene/Holocene transition are exceedingly rare in the Americas. Methodology/Principal Findings: Here we report a pecked anthropomorphic figure engraved in the bedrock of Lapa do Santo, an archaeological site located in Central Brazil. The horizontal projection of the radiocarbon ages obtained at the north profile suggests a minimum age of 9,370640 BP, (cal BP 10,700 to 10,500) for the petroglyph that is further supported by optically stimulated luminescence (OSL) dates from sediment in the same stratigraphic unit, located between two ages from 11.7 +/- 0.8 ka BP to 9.9 +/- 0.7 ka BP. Conclusions: These data allow us to suggest that the anthropomorphic figure is the oldest reliably dated figurative petroglyph ever found in the New World, indicating that cultural variability during the Pleistocene/Holocene boundary in South America was not restricted to stone tools and subsistence, but also encompassed the symbolic dimension.