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Abstract

The sustainable development model has largely failed to address the social and environmental challenges of the 21st century. True sustainability will only occur when it is valued as a part of the taken-for-granted daily life of individuals and cultures across the globe. This has not yet happened because humanity has not evolved a global consciousness quickly enough to match the global advances in telecommunications and transportation technologies that have created a socially and economically ever-shrinking planet. Travel and tourism contributes to the expansion of global consciousness, although only in a haphazard and unintentional manner. The COVID-19 pandemic is a result of planetary time-space compression and is forcing an expansion in human consciousness that will make humankind better able to address global problems. There will still be considerable diversity on the planet, as now, but the pandemic will stimulate growing numbers of people, businesses and governments to adopt new ways of thinking, behaving and operating that are more closely aligned with the goals of sustainable development. This could be further enhanced if travel and tourism were to adopt the expansion and awakening of global conscious as a fundamental and transformational value in the products and experiences that it offers.  相似文献   
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The goal of this paper is to assess the variation in the proportional contribution of diverse resources to the diet of human populations from northwest Patagonia (Argentina) throughout the Middle-Late Holocene. Particularly, we assessed the variation among three geographic areas and two periods. We first estimated the expected proportions of terrestrial animals and plants and aquatic resources for each area according to the Binford’s frames of references approach. A Bayesian mixing method was then applied to calculate the proportion of plants and animals in the diets from stable isotopes (δ13C and δ15N) of human bone collagen. The isotope values suggest that the composition of diets differed spatially and temporally. Diets of South Mendoza were mainly composed of terrestrial animals (Rhea-Lama and rodents) with a greater incorporation of C3 plants towards the later Late Holocene; in North Neuquén, Rhea and Lama represent a proportion of 0.84 of the diet consumed; and finally, the sample of Center Neuquén is the only one with high values of Araucaria in the diet. The isotopic values obtained for the three studied areas did not fit to the expectations of Binford’s model, North Neuquén being the area that departs most from the predicted proportions of terrestrial animals and plants and aquatic organisms in the diet. These findings open up new questions about the local conditions that influenced regional variation in the diet of prehistoric hunter-gatherers.  相似文献   
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This article presents the results of a 1991 household income survey of the three main groups in Cuban agriculture: wage workers on state farms, members of production co-operatives, and peasant producers. It is shown that since the 1959 revolution household income levels in the agricultural sector have improved dramatically, while regional differences have been ameliorated considerably. Households in the private sector of Cuban agriculture have fared the best. It is also demonstrated that agricultural households rely on multiple sources of income to generate their livelihood. Rather than being strictly proletarian, collective, or petty commodity producers, these households are best characterized by the multiple class relations in which they participate.  相似文献   
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The bioarchaeological record of South America is characterized by the high frequency of individuals with a variety of cranial deformations concentrated in three areas (North-West, Central-West and South) of this subcontinent. The general purpose of this paper is to study the variation in artificial cranial deformation in several regions of Central-West and South of South America. Cranial variation related to artificial deformation of human cranial remains is analyzed by means of geometric morphometrics and multivariate statistic methods. The results of this work show that there are no large differences in variation among states, chiefdoms and bands of hunter-gatherers. The pattern of variation observed in cranial deformation among regions can be interpreted principally according to the chronological and spatial distribution of the cranial samples analyzed.  相似文献   
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A simple and general method based on well-known random vibration theory is used to compute spectral attenuation relations at soft sites based on existing spectral attenuation relations at rock sites. The method consists of: (1) computation, for given magnitude and distance, of the expected Fourier amplitude spectrum associated with the median rock response spectrum computed with the attenuation relation; (2) inclusion of site effects characterized by a frequency-dependent, linear, or nonlinear transfer function; and (3) computation of the response spectrum at the soft site.  相似文献   
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