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1.
Sci Total Environ ; 684: 445-457, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31154217

RESUMO

This work focuses on the characterization of background levels of heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, Zn) in seabed marine sediments of the central Adriatic Sea, collected up to 10 km far from the Abruzzo region coastline (Italy). The used approach follows the guidelines established by the Decree of the Italian Ministry of Environment, n. 173/2016, concerning the determination of threshold values of metal concentration, and including only samples with low or absent toxicological content. A statistical analysis, using the adjusted Tuckey's boxplot to identify the percentiles and potential outliers, was performed. The background concentrations were calculated as the values of the 90th percentile of distribution, according to the national regulation. This study represents the first attempt to calculate the background levels of marine sediments done at regional level in Abruzzo. A few outliers have been found, and interpreted as potential anthropic contamination.

4.
BMJ Case Rep ; 20122012 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-22878981

RESUMO

Acute myelitis is an aetiologically heterogeneous inflammatory disorder of the spinal cord. We report on a 71-year-old woman with a recurrent cervical and thoracic myelitis who presented with a new relapse of the disease. Neuromyelitis optica was ruled out such as other possible causes of acute and/or recurrent myelopathy. Serum immunoglobulin levels and specific antibody responses were consistent with the diagnosis of common variable immunodeficiency (CVID). She was treated with high-dose methylprednisolone and intravenous immunoglobulin. As a remission-maintaining drug, we decided to treat her with subcutaneous immunoglobulin (CSL Behring) at 0.2 g/kg/week at doses higher than usually employed in replacement therapy in CVID. At 3-year follow-up, the response to treatment was good. No relapses occurred. Our case suggests the effectiveness and safety of subcutaneous immunoglobulin in maintaining remission and in sparing prednisone in a woman with recurrent myelitis associated with CVID.


Assuntos
Imunodeficiência de Variável Comum/imunologia , Imunoglobulinas/uso terapêutico , Metilprednisolona/uso terapêutico , Mielite/imunologia , Idoso , Autoanticorpos/sangue , Imunodeficiência de Variável Comum/complicações , Imunodeficiência de Variável Comum/tratamento farmacológico , Feminino , Humanos , Imunoglobulinas/administração & dosagem , Injeções Subcutâneas , Imageamento por Ressonância Magnética , Mielite/diagnóstico , Mielite/tratamento farmacológico , Dor/tratamento farmacológico , Qualidade de Vida , Recidiva , Tomografia Computadorizada por Raios X , Resultado do Tratamento
5.
Science ; 320(5880): 1182-5, 2008 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-18483402

RESUMO

The Shallow Radar (SHARAD) on the Mars Reconnaissance Orbiter has imaged the internal stratigraphy of the north polar layered deposits of Mars. Radar reflections within the deposits reveal a laterally continuous deposition of layers, which typically consist of four packets of finely spaced reflectors separated by homogeneous interpacket regions of nearly pure ice. The packet/interpacket structure can be explained by approximately million-year periodicities in Mars' obliquity or orbital eccentricity. The observed approximately 100-meter maximum deflection of the underlying substrate in response to the ice load implies that the present-day thickness of an equilibrium elastic lithosphere is greater than 300 kilometers. Alternatively, the response to the load may be in a transient state controlled by mantle viscosity. Both scenarios probably require that Mars has a subchondritic abundance of heat-producing elements.

6.
Astrobiology ; 8(1): 119-56, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18211229

RESUMO

We have investigated how morphological biosignatures (i.e., features related to life) might be identified with an array of viable instruments within the framework of robotic planetary surface operations at Mars. This is the first time such an integrated lab-based study has been conducted that incorporates space-qualified instrumentation designed for combined in situ imaging, analysis, and geotechnics (sampling). Specimens were selected on the basis of feature morphology, scale, and analogy to Mars rocks. Two types of morphological criteria were considered: potential signatures of extinct life (fossilized microbial filaments) and of extant life (crypto-chasmoendolithic microorganisms). The materials originated from a variety of topical martian analogue localities on Earth, including impact craters, high-latitude deserts, and hydrothermal deposits. Our in situ payload included a stereo camera, microscope, Mössbauer spectrometer, and sampling device (all space-qualified units from Beagle 2), and an array of commercial instruments, including a multi-spectral imager, an X-ray spectrometer (calibrated to the Beagle 2 instrument), a micro-Raman spectrometer, and a bespoke (custom-designed) X-ray diffractometer. All experiments were conducted within the engineering constraints of in situ operations to generate realistic data and address the practical challenges of measurement. Our results demonstrate the importance of an integrated approach for this type of work. Each technique made a proportionate contribution to the overall effectiveness of our "pseudopayload" for biogenic assessment of samples yet highlighted a number of limitations of current space instrument technology for in situ astrobiology.


Assuntos
Exobiologia/instrumentação , Sedimentos Geológicos/microbiologia , Marte , América , Regiões Antárticas , Carbonato de Cálcio/química , Sulfato de Cálcio/química , Sedimentos Geológicos/química , Alemanha , Compostos de Ferro/química , Minerais , Origem da Vida
7.
Science ; 317(5845): 1715-8, 2007 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-17885128

RESUMO

Mars' polar regions are covered with ice-rich layered deposits that potentially contain a record of climate variations. The sounding radar SHARAD on the Mars Reconnaissance Orbiter mapped detailed subsurface stratigraphy in the Promethei Lingula region of the south polar plateau, Planum Australe. Radar reflections interpreted as layers are correlated across adjacent orbits and are continuous for up to 150 kilometers along spacecraft orbital tracks. The reflectors are often separated into discrete reflector sequences, and strong echoes are seen as deep as 1 kilometer. In some cases, the sequences are dipping with respect to each other, suggesting an interdepositional period of erosion. In Australe Sulci, layers are exhumed, indicating recent erosion.


Assuntos
Marte , Meio Ambiente Extraterreno , Gelo
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