Peter O. Muller

SUBURBAN DOWNTOWNS AND THE TRANSFORMATION OF METROPOLITAN ATLANTA'S BUSINESS LANDSCAPE

The suburbanization of economic activity reached massive proportions in recent years and contributed significantly to the spatial restructuring of the American metropolis. One of the most important geographic expressions in the emergence of the outer suburban city is the clustering of high-order activities in new metropolitan-level urban centers. These complexes are here defined as suburban downtowns, and their rapid evolution since the 1960s is traced through a number of developmental stages. Two of metropolitan Atlantas suburban downtowns, which -ank among the largest in the United States, are highlighted in case studies in order to demonstrate the still-evolving dynamics that shape the functioning and internal structuring of these first-order activity complexes.

The Suburban Transformation of the Globalizing American City

As the American metropolis has turned inside out since 1970, the emerging outer suburban city has captured critical masses of leading urban activities from the central city that spawned it. Globalization increasingly shapes U.S. urban development in the 1990s, yet research to date has focused on the central city and mainly ignores the outer ring, where a growing majority of metropolitan residents live and work. Following a brief review of the unprecedented recent suburbanization of major economic activities, this article explores the rapidly expanding international role of suburban business complexes in large metropolitan areas, particularly Greater New York. Among the perspectives discussed are the world city hypothesis, relationships between telecommunications and urban form, high-technology industrial location processes, the influence of corporate headquarters on global information-flow networks, and the foreign presence in suburban America. It is concluded that globalization forces intensify and accelerate the suburban transformation of the American city. A new urban future is being shaped as fully developed suburbs become the engine driving metropolitan and world city growth.

Estimating regions of air trapping from electrical impedance tomography data

OBJECTIVE Electrical impedance tomography (EIT) has been shown to be a viable non-invasive, bedside imaging modality to monitor lung function. This paper introduces a method for identifying regions of air trapping from EIT data collected during tidal breathing and breath-holding maneuvers. APPROACH Ventilation-perfusion index maps are computed from dynamic EIT images. These maps are then used to identify regions of air trapping in the area of the lung as regions that are poorly ventilated but well perfused throughout the breathing and cardiac cycles. These EIT-identified regions are then compared with independently identified regions of low attenuation, or air trapping, on chest CT. Results of this method are demonstrated in two children with cystic fibrosis and on a healthy control subject. MAIN RESULTS In both CF children, the EIT-identified regions of air trapping matched the regions indicated from the chest CT. The EIT-based method is only validated with CT scans within 4 cm of the chest cross-section defined by the electrode plane. SIGNIFICANCE The results indicate the potential use of EIT-derived ventilation-perfusion index maps as a non-invasive method for identifying regions of air trapping.

Harm J. de Blij, 1935–2014

What Carl Sagan did for cosmology, Harm de Blij is doing for geography. See, hear, or read him and you will sign on for a continuing course in a subject that he has brought alive like no one else i...

Palimpsests: Biographies of 50 City Districts

The opening words of Paul Knox’s concise introductory essay get right at the heart of what this remarkable book is all about: “Cities reveal themselves in the moods and personalities of their districts” (p. 8). With the subtitle clarified, I’ll save you toggling over to the online dictionary (as the author thoughtfully did for his hard-copy readers). A palimpsest is “a manuscript written over a partly erased older manuscript in such a way that the old words can be read beneath the new” (p. 8).