304 research outputs found
Ciudades en un mundo de ciudades: El gesto comparativo
Cities exist in a world of cities and thus routinely invite a comparative gesture in urban theorizing. However, for some decades, urban studies have analytically divided the world of cities into, for example, wealthier and poorer, capitalist and socialist, or into different regional groupings of cities, with subsequently very little comparative research across these divides. Interest in drawing comparisons among different cities has escalated in an era of “globalization”, as economic and social activities as well as governance structures link cities together through spatially extensive flows of various kinds and intense networks of communication. Nonetheless, scholars of urban studies have been relatively reluctant to pursue the potential for international comparative research that stands at the heart of the field. Where an interest in globalization has drawn authors to explicit exercises in comparison, both the methodological resources and the prevalent intellectual and theoretical landscape have tended to limit and even undermine these initiatives. This article seeks, first, to understand why it is that in an intrinsically comparative field with an urgent contemporary need for thinking across different urban experiences, there has been relatively little comparative research, especially comparisons that stretch across the global North-South divide, or across contexts of wealthier and poorer cities. Secondly, through a review of existing strategies for comparing cities, the article considers the potential for comparative methodologies to overcome their limitations to meet growing demands for international and properly post-colonial urban studies. Finally, it proposes a new phase of comparative urban research that is experimental, but with theoretically rigorous foundations
The Need for Predatory Mortgage Education: Expert Views
This article describes the results of an exploratory study of predatory mortgage lending. The purposes were to gain insights into the salient characteristics of victims of predatory mortgage lending and identify the most effective means of victim protection in order to guide Extension efforts to educate consumers. Twelve mortgage-lending professionals were interviewed in-depth. They identified educational efforts by Extension educators and other nonprofit organizations as the best and most effective means of reducing the losses caused by predatory mortgage lending. Study findings can help Extension staff identify target audiences and the most effective educational strategies concerning predatory mortgage lending practices
Variation in fine-scale genetic structure and local dispersal patterns between peripheral populations of a South American passerine bird
Indexación: Scopus.The distribution of suitable habitat influences natal and breeding dispersal at small spatial scales, resulting in strong microgeographic genetic structure. Although environmental variation can promote interpopulation differences in dispersal behavior and local spatial patterns, the effects of distinct ecological conditions on within-species variation in dispersal strategies and in fine-scale genetic structure remain poorly understood. We studied local dispersal and fine-scale genetic structure in the thorn-tailed rayadito (Aphrastura spinicauda), a South American bird that breeds along a wide latitudinal gradient. We combine capture-mark-recapture data from eight breeding seasons and molecular genetics to compare two peripheral populations with contrasting environments in Chile: Navarino Island, a continuous and low density habitat, and Fray Jorge National Park, a fragmented, densely populated and more stressful environment. Natal dispersal showed no sex bias in Navarino but was female-biased in the more dense population in Fray Jorge. In the latter, male movements were restricted, and some birds seemed to skip breeding in their first year, suggesting habitat saturation. Breeding dispersal was limited in both populations, with males being more philopatric than females. Spatial genetic autocorrelation analyzes using 13 polymorphic microsatellite loci confirmed the observed dispersal patterns: a fine-scale genetic structure was only detectable for males in Fray Jorge for distances up to 450 m. Furthermore, two-dimensional autocorrelation analyzes and estimates of genetic relatedness indicated that related males tended to be spatially clustered in this population. Our study shows evidence for context-dependent variation in natal dispersal and corresponding local genetic structure in peripheral populations of this bird. It seems likely that the costs of dispersal are higher in the fragmented and higher density environment in Fray Jorge, particularly for males. The observed differences in microgeographic genetic structure for rayaditos might reflect the genetic consequences of population-specific responses to contrasting environmental pressures near the range limits of its distribution.http://onlinelibrary.wiley.com/doi/10.1002/ece3.3342/epd
A renormalization procedure for tensor models and scalar-tensor theories of gravity
Tensor models are more-index generalizations of the so-called matrix models,
and provide models of quantum gravity with the idea that spaces and general
relativity are emergent phenomena. In this paper, a renormalization procedure
for the tensor models whose dynamical variable is a totally symmetric real
three-tensor is discussed. It is proven that configurations with certain
Gaussian forms are the attractors of the three-tensor under the renormalization
procedure. Since these Gaussian configurations are parameterized by a scalar
and a symmetric two-tensor, it is argued that, in general situations, the
infrared dynamics of the tensor models should be described by scalar-tensor
theories of gravity.Comment: 20 pages, 3 figures, references added, minor correction
Hyperbaric storage of raw milk at room temperature
info:eu-repo/semantics/publishedVersio
A microbiological perspective of raw milk preserved at room temperature using hyperbaric storage compared to refrigerated storage
The effects of hyperbaric storage (HS, 50–100 MPa) at room temperature (RT) on endogenous and inoculated pathogenic surrogate vegetative bacteria (Escherichia coli, Listeria innocua), pathogenic Salmonella enterica and bacterial spores (Bacillus subtilis) were assessed and compared with conventional refrigeration at atmospheric pressure for 60 days. Milk stored at atmospheric pressure and refrigeration quickly surpassed the acceptable microbiological limit within 7 days of storage, regarding endogenous microbiota, yet 50 MPa/RT slowed down microbial growth, resulting in raw milk spoilage after 28 days, while a significant microbial inactivation occurred under 75–100 MPa (around 4 log units), to counts below 1 log CFU/mL throughout storage, similar to what was observed for B. subtilis endospores. While inoculated microorganisms had a gradually counts reduction in all HS conditions. Results indicate that HS can not only result in the extension of milk shelf-life but is also able to enhance its safety and subsequent quality. Industrial relevance: This new preservation methodology could be implemented in the dairy farm storage tanks, or during milk transportation for further processing, allowing a better microbial control, than refrigeration. This methodology is very promising, and can improve food products shelf-life with a considerable lower carbon foot-print than refrigeration.info:eu-repo/semantics/publishedVersio
Infrared spectroscopy and flow analysis for the determination of chemical constituents in food products
Two analytical methods were proposed for
the determination of sodium chloride. A flow
injection turbidimetric determination, based
on the precipitation of silver chloride, was
found to be a simple methodology to be
implemented for routine analysis with a high
sampling frequency, low reagent consumption and waste production in comparison with the reference methodology. On the other hand, the
infrared methodology allowed NaCl
determination with no reagent consumption.
Both methodologies can be implemented
for routine chemical analysis determinations
in the food industry
Monitoring sodium chloride during cod fish desalting process by flow injection spectrometry and infrared spectroscopy
In order to adapt to the market trends that are moving towards ready-to-use products cod !sh industry is
including into their industrial operations as the desalting step. The desalting process is a high cost and
time demanding operation. The optimization of the desalting process is of vital importance for the !sh
industry in order to assure the homogeneity and predictable concentration of sodium chloride in the
!nal hydrated cod !sh product. On the other hand, consumers are more aware about the necessity to
bring sodium consumption down to healthy levels to prevent cardiovascular diseases. The application of
rapid and simple analytical methodologies that permit the control of the process and ensure food quality
is essential in the food industries.
This work reports the optimization and application of two analytical methodologies with the objective
of monitoring the variation of sodium chloride concentration during cod desalting process. A "ow
injection analysis system was developed based on the reaction between chloride and silver nitrate, and
the formed precipitate was assessed spectrophotometrically as a turbidity change. A Fourier-mid infrared
spectroscopy attenuated total re"ection method was also applied. Different chemical and physical
parameters of the "ow injection system were studied and the analytical characteristics of both systems
were compared.info:eu-repo/semantics/acceptedVersio
- …