Nine-year trajectory of a SOFAR float in the southwestern North Atlantic

A SOFAR float at a depth of approximately 100 m was tracked intermittently for 9 years, the longest such trajectory ever obtained. This instrument was launched near 24N, 69W in October 1976. Tracking ceased when it was near 22N, 56W in June 1985. The llong-term drift was ≈1 cm s-1 eastward, in agreement with a few other 700 m floats and with geostrophic flow estimates for this region. The kinetic energy level of 20 cm2 s-2 is similar to those observed by current meters in the ocean interior away from western boundary currents, but eddy variability is more concentrated in the mesoscale frequencies. The zonal and meridional variances are roughly the same. © 1988

FTIR spectroscopy of the atmosphere Part 2. Applications

The basic principles and methods of FTIR spectroscopy of the atmosphere were summarized in our previous paper (1). Thanks to the continuous technical development of FTIR spectroscopy (increasing throughput, dynamic alignment, more sensitive detectors, brighter sources, increasing scanning speed, development of focal plane array detectors, flexible spectral manipulations and data handling, etc.) in the last decade, this method has offered a great number of unique applications. In this review article, attempt to summarize the results of the most significant and frequent applications of FTIR spectroscopy to the study of the atmosphere. The possibilities of techniques applied in this field, the extractive and open path measurement methods, and the in situ IR absorption measurements such as remote sensing using the sun, the sky, or natural hot objects as IR sources of radiation are discussed. We have made a special focus to FTIR emission spectroscopy, the so-called passive technique, since there are a number of originally hot gaseous samples such as volcanic plumes, automobile gases, stack gas plumes, or flames. Most of the subjects discussed in this article can be closely related to environmental analysis of the atmosphere. There is a wide range of atmospheric environmental applications of FTIR spectroscopy; therefore, we have focused our attention in the second part of the article on applications of FTIR spectroscopy in the atmosphere (troposphere) and stratosphere. We have summarized the basic literature in the field of special environmental applications of FTIR spectroscopy, such as power plants, petrochemical and natural gas plants, waste disposals, agricultural, and industrial sites, and the detection of gases produced in flames, in biomass burning, and in flares

Radiograma de tórax e tomografia computadorizada na avaliação do enfisema pulmonar Chest X-ray and computed tomography in the evaluation of pulmonary emphysema

O enfisema é uma condição do pulmão, caracterizada pelo aumento acima do normal no tamanho dos espaços aéreos distais ao bronquíolo terminal. Atualmente, o enfisema é a quarta causa de morte nos EUA, afetando 14 milhões de pessoas. O presente artigo descreve as principais ferramentas no diagnóstico por imagem do enfisema, desde o início até os dias de hoje. Relata as técnicas tradicionais, como radiograma de tórax, e as evoluções no campo da tomografia computadorizada (TC), como a TC de alta resolução e a densitovolumetria pulmonar por TC tridimensional.<br>Emphysema is a condition of the lung, characterized by the abnormal increase in the size of the airspace distal to the terminal bronchioles. Currently, emphysema is the fourth leading cause of death in the USA, affecting 14 million people. The present article describes the principal tools in the imaging diagnosis of emphysema, from the early days until the present. We describe traditional techniques, such as chest X-ray, together with the evolution of computed tomography (CT) to more advanced forms, such as high resolution CT, as well as three-dimensional CT densitometry and volumetric assessment