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31.
ABSTRACT This paper surveys recent evidence on the determinants of (national and/or foreign) industrial location. We find that the basic analytical framework has remained essentially unaltered since the early contributions of the early 1980s while, in contrast, there have been advances in the quality of the data (more firm and plant level information, geographical disaggregation, panel structure, etc.) and, to a lesser extent, the econometric modeling. We also identify certain determinants (neoclassical and institutional factors) that tend to provide largely consistent results across the reviewed studies. In light of this evidence, we finally suggest future lines of research.  相似文献   
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33.
Small mammals are considered to be good indicators of ancient environments. One particular layer in a fortification tower of a Mediterranean Iberian village, Alorda Park (4th century BC), provided a large amount of well-preserved small mammal bones (about 19,200 remains) probably accumulated by barn owls (Tyto alba). Such an accumulation is rarely available from the Iron Age. It provides not only palaeoenvironmental data, but also further information about other studies such as morphometrics, ancient DNA and zoogeography. This article focuses on the ecological data, and attempts to develop an accurate taphonomic study to assess the reliability and statistical significance of this archaeological sample.  相似文献   
34.
This article comments upon the situation of sprawl in Spain and Madrid, especially residential sprawl. It does not appear to be a serious problem due to its low starting point, but artificial surface and residential sprawl is growing rapidly. For that reason, it may be an issue in the future. Between 2000 and 2006, urban residential land use grew 0.4% in Spain and 0.2% in Europe per year, land use of industrial and commercial areas grew 2.3% in Spain and 0.4% in Europe and total artificial surface grew 2.7% in Spain and 0.6% in Europe (EEA, 2010). Further, we will study the legislation on maximum and minimum urban density in Spain. The highest maximum urban density is established by the Basque Country, with 230 dwellings per hectare, and the highest minimum urban density is established by Catalonia, with 50 dwellings per hectare. In both cases, it is applied to only certain types of territories. Finally, we will analyse what happens in the Region of Madrid in relation to sprawl. It has very similar patterns compared with the rest of Spain, although more pronounced.  相似文献   
35.
This article analyzes the mechanisms through which metropolitan governance is established in Montreal's aeronautics sector, one of the most important and innovative industries in the region. The article also examines the role of lead firms, socio‐economic actors, and public agencies from a territorial point of view. It is established that on the one hand the existence of a small number of prime producers at the local level facilitates productive linkages among businesses through subcontracting, and on the other hand, the intensive participation of intermediate socio‐economic agencies and organizations ensures a metropolitan anchoring of the sector and creates a strong territorial identity among the players.  相似文献   
36.
This paper argues that observing neighborhood movements through the lens of territorial state restructuring holds theoretical promise. Contemporary struggles over municipal decentralization need to be located within broader state re-scaling processes. Seeking to contribute a Latin American perspective to the largely Anglo-American field of urban neoliberalization research, this study engages with the emergence of local autonomy claims in Buenos Aires, Argentina. Middle-class activists and organizations advanced such claims against the background of thorough transnationalism, in what may be interpreted as a localist political reaction to the socio-spatial consequences of urban and state restructuring. Field evidence is used to assess the ultimate political efficacy and democratic implications of their political agency, particularly in what concerns municipal decentralization. It is argued that curtailing the empowerment of barrio districts were the following conditions: mayoral opposition to communal reforms; ongoing cross-scalar tensions between the city and national government; and the barrio-centric issue framings of activists, which hampered social recruitment in an increasingly heterogeneous and transnationalized urban space.  相似文献   
37.
Bones treated at low temperature do not present major modifications although, macroscopically, boiled bones may be distinguished from unboiled ones as they are smoother, lighter and more transparent. Such observations should correspond to textural modifications at a nanometric level and should depend on boiling time. In this study, contemporary human bones, boiled during various time intervals, were characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and nitrogen adsorption (BET). The results were used to estimate the boiling time in four archaeological samples (Neolithic bones from Malalmuerzo cave, Spain). It is concluded, comparing Neolithic bones to contemporary ones and from the textural characterization at a nanometrical level, that two of the archaeological bones were boiled and that they were boiled for less than 6 hours.  相似文献   
38.
We present a scheme to modify empirical Green's functions by attenuation considering: (1) geometrical spreading; (2) decay in high frequency; (3) regional attenuation; and (4) phase of the signal. The accelerograms computed with the proposed simulation method are compared, in time and frequency domains, with strong ground motions from subduction and intermediate-depth earthquakes recorded in Mexico. It is shown that this simple empirical Green's functions technique can synthesize both the shape and amplitude of the response spectra in the site, considering a postulated seismic source located at different distances from the original one.  相似文献   
39.
Ground-supported steel tanks experienced extensive damage in past earthquakes. The failure of tanks in earthquakes may cause severe environmental damage and economic losses. This study deals with the evaluation of the elastic buckling of above-ground steel tanks anchored to the foundation due to seismic shaking. The proposed nonlinear static procedure is based on the capacity spectrum method (CSM) utilized for the seismic evaluation of buildings. Different from the standard CSM, the results are not the base shear and the maximum displacement of a characteristic point of the structure but the minimum value of the horizontal peak ground acceleration (PGA) that produces buckling in the tank shell. Three detailed finite element models of tank-liquid systems with height to diameter ratios H/D of 0.40, 0.63, and 0.95 are used to verify the methodology. The 1997 UBC design spectrum and response spectra of records of the 1986 El Salvador and 1966 Parkfield earthquakes are used as seismic demand. The estimates of the PGA for the occurrence of first elastic buckling obtained with the proposed nonlinear static procedure were quite accurate compared with those calculated with more elaborate dynamic buckling studies. For all the cases considered, the proposed methodology yielded slightly smaller values of the critical PGA for the first elastic buckling compared to the dynamic buckling results.  相似文献   
40.
Abstract

Multiple sclerosis (MS) was first presented in a clinical setting in 1838. In this paper the presentation and treatment of a transient hemiparesis in a drummer in 1789 is discussed. This may have been an early case of MS and presents evidence against the theory that MS is an infectious disease beginning in the 19th century.  相似文献   
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