291 research outputs found
Remote sensors applied to the prospecting of thermomineral waters in the municipality of Caldas Novas-Goias
There are no author-identified significant results in this report
Methodology of the interpretation of remote sensing data and applications in geology
Methods used for interpreting orbital (LANDSAT) data for regional geological mapping in Brazil are examined. Particular attention is given to the levels of analysis used for studying geomorphology, structural geology, lithology, stratigraphy, surface geology, and dynamic processes. Examples of regional mapping described include: (1) rock intrusions in SE Sao Paulo, the southern parts of Minas Gerais, and the states of Rio de Janeiro, and Espiritu Santo; (2) a preliminary survey of Pre-Cambrian geology in the State of Piaui; and (3) the Gondwana Project - surveying Jaguaribe plants. Mineral exploration in Rio Grande do Sul, and the geology of the Alcalino complex of Itatiaia are discussed as well as the use of automatic classifications of rock intrusions and of ilmenite deposits in the Floresta Region. Aerial photography, side looking radar, and thermal infrared scanning are other types of remote sensors also used in prospecting for geothermal anomalies in the city of Caldas Novas-Goias
LANDSAT and radar mapping of intrusive rocks in SE-Brazil
The feasibility of intrusive rock mapping was investigated and criteria for regional geological mapping established at the scale of 1:500,00 in polycyclic and polymetamorphic areas using the logic method of photointerpretation of LANDSAT imagery and radar from the RADAMBRASIL project. The spectral behavior of intrusive rocks, was evaluated using the interactive multispectral image analysis system (Image-100). The region of Campos (city) in northern Rio de Janeiro State was selected as the study area and digital imagery processing and pattern recognition techniques were applied. Various maps at the 2:250,000 scale were obtained to evaluate the results of automatic data processing
Methodology of remote sensing data interpretation and geological applications
Elements of photointerpretation discussed include the analysis of photographic texture and structure as well as film tonality. The method used is based on conventional techniques developed for interpreting aerial black and white photographs. By defining the properties which characterize the form and individuality of dual images, homologous zones can be identified. Guy's logic method (1966) was adapted and used on functions of resolution, scale, and spectral characteristics of remotely sensed products. Applications of LANDSAT imagery are discussed for regional geological mapping, mineral exploration, hydrogeology, and geotechnical engineering in Brazil
Study project of intrusive rocks: States of Espirito Santo and Rio de Janeiro, south and east of Minas Gerais and southeast of the state of Sao Paulo
The feasibility of mapping intrusive rocks in polycyclic and polymetamorphic areas using the logic method for photointerpretation of LANDSAT and radar imagery was investigated. The resolution, scale and spectral characteristics of the imagery were considered. Spectral characteristics of the intrusive rock units mapped using image 100 were investigated. It was determined that identification of acidic and basic intrusive bodies and determination of their relationships with principal structural directions using the logic method was feasible. Tectonic compartments were subdivided into units according to their predominant lithographic types, ignoring stratigraphy. The principal directions of various foliations, faults, megafolds, and fractural systems were defined. Delineation of the boundaries of intrusive bodies mapped using the spectral characteristics of Image 100 imagery ws determined to be more accurate than visual analysis. A 1:500,000 scale map of intrusions in the areas studied was generated
Human γδ T-Cells: from surface receptors to the therapy of high-risk leukemias
γδ T lymphocytes are potent effector cells, capable of efficiently killing tumor and leukemia cells. Their activation is mediated by γδ T-cell receptor (TCR) and by activating receptors shared with NK cells (e.g., NKG2D and DNAM-1). γδ T-cell triggering occurs upon interaction with specific ligands, including phosphoantigens (for Vγ9Vδ2 TCR), MICA-B and UL16 binding protein (for NKG2D), and PVR and Nectin-2 (for DNAM-1). They also respond to cytokines undergoing proliferation and release of cytokines/chemokines. Although at the genomic level γδ T-cells have the potential of an extraordinary TCR diversification, in tissues they display a restricted repertoire. Recent studies have identified various γδ TCR rearrangements following either hematopoietic stem cell transplantation (HSCT) or cytomegalovirus infection, accounting for their "adaptive" potential. In humans, peripheral blood γδ T-cells are primarily composed of Vγ9Vδ2 chains, while a minor proportion express Vδ1. They do not recognize antigens in the context of MHC molecules, thus bypassing tumor escape based on MHC class I downregulation. In view of their potent antileukemia activity and absence of any relevant graft-versus-host disease-inducing effect, γδ T-cells may play an important role in the successful clinical outcome of patients undergoing HLA-haploidentical HSCT depleted of TCR αβ T/CD19+ B lymphocytes to cure high-risk acute leukemias. In this setting, high numbers of both γδ T-cells (Vδ1 and Vδ2) and NK cells are infused together with CD34+ HSC and may contribute to rapid control of infections and leukemia relapse. Notably, zoledronic acid potentiates the cytolytic activity of γδ T-cells in vitro and its infusion in patients strongly promotes γδ T-cell differentiation and cytolytic activity; thus, treatment with this agent may contribute to further improve the patient clinical outcome after HLA-haploidentical HSCT depleted of TCR αβ T/CD19+ B lymphocytes
On bulk singularities in the random normal matrix model
We extend the method of rescaled Ward identities of Ameur-Kang-Makarov to
study the distribution of eigenvalues close to a bulk singularity, i.e. a point
in the interior of the droplet where the density of the classical equilibrium
measure vanishes. We prove results to the effect that a certain "dominant part"
of the Taylor expansion determines the microscopic properties near a bulk
singularity. A description of the distribution is given in terms of a special
entire function, which depends on the nature of the singularity (a
Mittag-Leffler function in the case of a rotationally symmetric singularity).Comment: This version clarifies on the proof of Theorem
The effect of temperature mixing on the observable (T,beta)-relation of interstellar dust clouds
Detailed studies of the shape of dust emission spectra are possible thanks to
the current instruments capable of observations in several sub-millimetre bands
(e.g., Herschel and Planck). However, some controversy remains even on the
basic effects resulting from the mixing of temperatures along the
line-of-sight.
Studies have suggested either a positive or a negative correlation between
the colour temperature T_C and the observed spectral index beta_Obs. Our aim is
to show that both cases are possible and to determine the factors leading to
either behaviour. We start by studying the sum of two or three modified black
bodies of different temperature. With radiative transfer modelling, we examine
the probability distributions of the dust mass as a function of the physical
dust temperature. With these results as a guideline, we examine the (T_C,
beta_Obs) relations for different sets of clouds.
Even in the case of modified blackbodies at temperatures T_0 and T_0+ Delta
T_0, the correlation between T_C and beta_Obs can be either positive or
negative. If one compares models where Delta T_0 is varied, the correlation is
negative. If the models differ in their mean temperature T_0 rather than in
Delta T_0, the correlation remains positive. Radiative transfer models show
that externally heated clouds have different mean temperatures but the widths
of their temperature distributions are rather similar. Thus, the correlation
between T_C and beta_Obs is expected to be positive. The same result applies to
clouds illuminated by external radiation fields of different intensity. For
internally heated clouds a negative correlation is the more likely alternative.
If the signal-to-noise ratio is high, the observed negative correlation could
be explained by the temperature dependence of the dust optical properties but
that intrinsic dependence could be even steeper than the observed one.Comment: Accepted to A&
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