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1.
The most significant environmental benefit of recycling or reusing a wide range of products and materials is typically the potential to displace primary material production; lack of displacement significantly reduces the environmental benefits of these activities. Because no consensus method to estimate displacement rate has emerged, environmental assessments have tended to assume that displacement occurs on a one‐to‐one basis. However, displaced production is a complex phenomenon governed primarily by market mechanisms, rather than physical relationships. This article advances the understanding of displacement by presenting a market‐based framework describing the displacement relationship and a methodology for quantifying displacement rate based on partial equilibrium modeling. Using this methodology, a general symbolic equation for displacement rate after an increase in recycling is derived. The model highlights the market mechanisms that govern displaced production and identifies five price response parameters that affect displacement rate. Results suggest that one‐to‐one displacement occurs only under specific parameter restrictions that are unlikely in competitive commodity markets, but zero displacement is possible if secondary materials are poor substitutes for primary materials; displacement is likely to be reduced if secondary materials have inferior technical properties. The presented methodology can be generally applied to any system in which recycled or reused materials are substitutes or complements for primary materials. Implications for improving recycling and reuse efficacy and environmental assessment methodology are discussed, and suggestions are presented for expanding the displacement methodology in future research.  相似文献   

2.
Cultural homogenization has accompanied many of the most destructive processes of mass displacement during the Twentieth century. Its goal has been to make polity and citizens ethnically and culturally ‘congruent’. This article questions the explanatory power of traditional accounts linking cultural homogenization with industrialization during state-building processes and the emergence of nationalism. It suggests that further attention must be paid to the role of the military as an essential institution in both of these processes. Finally, the ‘egalitarian’ rhetoric and legitimizing rationale underpinning both militarization and cultural homogenization is assessed as a most powerful nationalist tool for imposing new hierarchical structures.  相似文献   

3.
Much has been written about how law as an institution has developed to solve many problems that human societies face. Inherent in all of these explanations are models of how humans make decisions. This article discusses what current neuroscience research tells us about the mechanisms of human decision making of particular relevance to law. This research indicates that humans are both more capable of solving many problems than standard economic models predict, but also limited in ways those models ignore. This article discusses how law is both shaped by our cognitive processes and also shapes them. The article considers some of the implications of this research for improving our understanding of how our current legal regimes operate and how the law can be structured to take advantage of our neural mechanisms to improve social welfare.  相似文献   

4.
Focusing on Lakatoro, a provincial centre in Vanuatu, this article explores the ways in which a state institution may allow kastom‐based sociality to proceed for the local population. Rather than considering kastom and the state as necessarily separate, it is demonstrated that the institutions of the state can provide the objective forms needed for kastom to exist in urban space. The article discusses three ways in which this happened—through a staff handbook, daily prayer meetings, and a court case—arguing that ‘the province’s’ polyvalence provided a means by which Lakatoro could be experienced as a place. And that this, in turn, provided a way in which the local population could understand the town to be imbued with appropriate sociality, as measured by kastom.  相似文献   

5.
Long bones respond to mechanical loading through functional adaptation in a suite of morphological characteristics that together ensure structural competence to in vivo loading. As such, adult bone structure is often used to make inferences about past behavior from archaeological remains. However, such biomechanical approaches often investigate change in just one aspect of morphology, typically cross‐sectional morphology or trabecular structure. The relationship between longitudinal bone curvature and mobility patterns is less well understood, particularly in the tibia, and it is unknown how tibial curvature and diaphyseal cross‐sectional geometry interact to meet the structural requirements of loading. This study examines tibial curvature and its relationship with diaphyseal cross‐sectional geometry (CSG) and body size in preindustrial Central Europeans spanning ~6150 years following the introduction of agriculture in the region. Anteroposterior centroid displacement from the proximo‐distal longitudinal axis was quantified at nine diaphyseal section locations (collectively representative of diaphyseal curvature) in 216 tibial three‐dimensional laser scans. Results documented significant and corresponding temporal declines in midshaft centroid displacement and CSG properties. Significant correlations were found between mid‐diaphyseal centroid displacement and all mobility‐related CSG properties, while the relationship weakened toward the diaphyseal ends. No significant relationship was found between centroid displacement and body size variables with the exception of the most distal section location. Results support a relationship between tibial curvature and cross‐sectional geometry among prehistoric Central European agricultural populations, and suggest that changes in mechanical loading may have influenced a suite of morphological features related to bone adaptation in the lower limb. Am J Phys Anthropol 157:260–275, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   

6.
Research into the character of social relationships in psychiatric inpatient facilities has focused on face-to-face interaction between individuals and within groups in the communal areas of wards. Using theories developed in material culture and media studies, this article argues that patients’ relationships to goods, namely, photographs, cards and gifts from family or friends, televisions and radios, are important mediators and constituents of sociability. In an ethnographic study of a medium-secure psychiatric unit, I show how these goods are put to use in private space in ways that reflect and mitigate the constraints of incarceration and stigmatization. The data were derived from 3 months of participant observation on a male and a female ward at a unit in the south of England, including a series of anthropological interviews with 19 patients. This article highlights two important findings. First, potentially isolating activities are perceived by patients as sociable, in that watching television and looking at photographs in their room helps to counter feelings of loneliness and isolation. Second, potentially sociable activities, exchanging goods or watching the communal television, are often practiced in such a way as to maintain distance between patients in acknowledgment of the constrained and volatile nature of these relationships. This suggests that patients aspire to retain a sense of the artificiality of their situation, preferring to confine their notion of ‘real’ relationships to those that exist outside the institution.  相似文献   

7.
In this article I use an ethnographic approach to consider the causes and consequences of a focus on ‘survivor’ experience in Canada's Truth and Reconciliation Commission (TRC) on Indian residential schools. In this Truth Commission, the interconnected concepts of ‘survivor’, ‘cultural genocide’, ‘trauma’, and ‘healing’ became reference points for much of the testimony that was presented and the ways the schools were represented. Canada's Truth Commission thus offers an example of the consequences of ‘victim centrism’, including the ways that ‘truth‐telling’ can be influenced by the affirmation of particular survivor experiences and the wider goal of reforming the dominant historical narrative of the state through public education. Canada's TRC was limited by its mandate to a particular kind of institution and scope of collective harm. It was at the same time active in its creation of narrative templates, which guided the expression of traumatic personal experience and affirmed the category of residential school ‘survivor’ as the focal point for understanding policy‐driven loss of language, tradition, and political integrity.  相似文献   

8.
This article addresses experiences of belonging and place-making among indigenous Mapuche youths in Santiago, Chile. Moving from a collaborative ethnography, it elaborates on the emplacement of the tuwün (place of origin) – usually linked to ancestral territories – within the city, and the meanings this shift entails. Furthering knowledge on indigenous spatiality by addressing migration, the analysis focuses on the ambivalent ways in which memory, affect, and power relations are embedded in urban materialities, and are negotiated through ‘acts of traversing’. The significant relationship between persons and places is conceived as mediated by movement, expanding on the creative possibilities of routing. Moreover, drawing on practice-based methods, the article argues for a shared engagement with research participants in order to gain a deeper understanding of the ways in which place- and self-making in contexts of migration encompass both rupture and creative reappropriation, contributing to current debates on displacement and the sense of place.  相似文献   

9.
Substance flow analysis (SFA) is a frequently used industrial ecology technique for studying societal metal flows, but it is limited in its ability to inform us about future developments in metal flow patterns and how we can affect them. Equation‐based simulation modeling techniques, such as dynamic SFA and system dynamics, can usefully complement static SFA studies in this respect, but they are also restricted in several ways. The objective of this article is to demonstrate the ability of agent‐based modeling to overcome these limitations and its usefulness as a tool for studying societal metal flow systems. The body of the article summarizes the parallel implementation of two models—an agent‐based model and a system dynamics model—both addressing the following research question: What conditions foster the development of a closed‐loop flow network for metals in mobile phones? The results from in silico experimentation with these models highlight three important differences between agent‐based modeling (ABM) and equation‐based modeling (EBM) techniques. An analysis of how these differences affected the insights that could be extracted from the constructed models points to several key advantages of ABM in the study of metal flow systems. In particular, this analysis suggests that a key advantage of the ABM technique is its flexibility to enable the representation of societal metal flow systems in a more native manner. This added flexibility endows modelers with enhanced leverage to identify options for steering metal flows and opens new opportunities for using the metaphor of an ecosystem to understand metal flow systems more fully.  相似文献   

10.
Elucidating the relationship between genetic and cultural evolution is important in understanding speciation, as learned premating barriers might be involved in maintaining species differences. Here, we test this relationship by examining a widely recognized premating barrier, bird song, in a hybrid zone between black‐throated green (Setophaga virens) and Townsend's warblers (S. townsendi). We use song analysis, genomic techniques and playback experiments to characterize the cultural and genetic backgrounds of individuals in this region, expecting that if song is an important reproductive barrier between these species, there should be a strong relationship between song and genotype. We show that songs in the hybrid zone correspond to the distinctly different songs found in allopatry but that song and genotype are not tightly coupled in sympatry. Allopatric individuals responded only to local songs, indicating that individuals may have learned to respond to songs they commonly hear. We observed discordance between song and genotype clines; a narrower cline suggests that cultural selection on song is stronger than natural selection on genotype. These findings indicate that song is unlikely to play a role in reproductive isolation between these species, and we suggest that spatial variation in song may nonetheless be maintained by frequency‐dependent cultural selection. This decoupling of genes and culture may contribute to hybridization in this region.  相似文献   

11.
Bridget Pratt 《Bioethics》2019,33(7):805-813
Undertaking engagement in public health research is ethically essential. There is a growing emphasis on practicing engagement as the co‐construction of knowledge, which goes beyond other common forms of engagement in health research practice: consulting and informing. Taking such an approach means researchers jointly construct knowledge with research users and beneficiaries; all parties design and conduct research together and share decision‐making power. This article makes the normative argument that such engagement is necessary to achieve the foundational moral aims of public health research—building relations of equality and addressing the health needs of those considered disadvantaged—which reflect the field's underlying commitment to social justice. It next identifies and discusses three ways in which co‐constructing knowledge advances those moral aims: by facilitating self‐determination, supporting individuals’ right to research, and maximizing social knowledge to address cognitive and epistemic injustice. Objections to the arguments presented in the article are then articulated and defended against.  相似文献   

12.
The mean annual rainfall in southern Africa is found to explain over half of the observed variance in the stable nitrogen (N) isotopic signatures of C3 vegetation in southern Africa (r2=0.54, P<0.01). The inverse relationship between the stable N isotopic signatures of foliar samples from C3 vegetation and long‐term southern African rainfall is found on a scale larger than previously observed. A modest relationship is found between stable carbon (C) isotopic signatures of C3 vegetation and rainfall across the region (r2=0.20, P<0.01). No such relationship is found between stable C and N isotopic signatures of C4 vegetation and rainfall. The explanation of the relationship between 15N in C3 vegetation and the mean annual rainfall presented here is that nutrient availability varies inversely with water availability. This suggests that water‐limited systems in southern Africa are more open in terms of nutrient cycling and therefore the resulting natural abundance of foliar 15N in these systems is enriched. The use of this relationship may be of value to those researchers modeling both the dynamics of vegetation and biogeochemistry across this region. The use of the isotopic enrichment in C3 vegetation as a function of rainfall may provide an insight into nutrient cycling across the semi‐arid and arid regions of southern Africa. This finding has implications for the study of global change, especially as it relates to vegetation responses to changing regional rainfall regimes over time.  相似文献   

13.
While end capping in α‐helices is well understood, the concept of capping a β‐hairpin is a relatively recent development; to date, favorable Coulombic interactions are the only example of sidechains at the termini influencing the overall stability of a β‐hairpin. While cross‐strand hydrophobic residues generally provide hairpin stabilization, particular when flanking the turn region, those remote from this location appear to provide little stabilization. While probing for an optimal residue at a hydrogen bond position near the terminus of a designed β‐hairpin a conservative, hydrophobic, V → I mutation was observed to not only result in a significant change in fold population but also effected major changes in the structuring shifts at numerous sites in the peptide. Mutational studies reveal that there is an interaction between the sidechain at this H‐bonded site and the sidechain at the C‐terminal non‐H‐bonded site of the hairpin. This interaction, which appears to be hydrophobic in character, requires a highly twisted hairpin structure. Modifications at the C‐terminal site, for example an E → A mutation (ΔΔGU = 6 kJ/mol), have profound affects on fold structure and stability. The data suggests that this may be a case of hairpin end capping by the formation of a hydrophobic cluster. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 557–564, 2009. This article was originally published online as an accepted preprint. The “Published Online”date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com  相似文献   

14.
Ecological speciation appears to contribute to the diversification of insect herbivores and other parasites, which together comprise a major component of Earth's biodiversity. Host shifts are likely an important step in ecological speciation, and understanding how such shifts occur is critical to forming and testing hypotheses explaining parasite diversity. In this article, I argue that phenotypic variation in hosts arising from environmental variation (phenotypic plasticity) can promote shifts in parasites by bridging both spatiotemporal and phenotypic gaps between ancestral and novel hosts. This hypothesis, which I call the ‘plastic‐bridge hypothesis’, is conceptually distinct from those invoking genetic variation in bridging these gaps. I describe the mechanistic basis of plastic bridges, review circumstantial evidence in support of the hypothesis and suggest strategies for testing it. I use herbivorous insects and their host plants as a model, but the proposed ideas apply to any system fitting a broad definition of a host‐parasite relationship. The plastic‐bridge perspective suggests that parasite diversity is not only due to divergent selection provided by hosts, but also to the intraspecific variation that facilitates shifts between them. This view is timely, as biological invasion and range shifts associated with climate change foster novel interactions between parasites and hosts.  相似文献   

15.
Abstract I investigated the relationship between species richness and composition of ant faunas, and sampling intensity in two regions with different long‐term histories of grazing intensity in mulga (Acacia aneura) woodlands in northern New South Wales. There were two aims: (i) to examine the relationship between sampling intensity and species richness and composition; and (ii) to explore the differences in ant assemblages from two regions of markedly different grazing intensity when sampled at different intensities (i.e. when a higher proportion of the local ant fauna were collected). Ants were sampled in pit traps (120‐mm diameter) at densities of two, four, six and nine pits per 100 m2. Each sampling‐intensity treatment was replicated three times within each region. Pit traps filled with preservative were opened for 3 days. Species richness was higher with each successive increase in sampling intensity but was not different between regions for a given trapping intensity. There was no obvious asymptote of the curve relating trapping intensity to cumulative species richness suggesting that even greater trap densities than those used in the present study would be needed to collect most of the species of ants using a patch of ground over a few days. Spatial replication of a low‐intensity sampling design did not capture as many species as one higher‐intensity sampling array with the same total number of pit traps. This result can be explained by aggressive numerically dominant species of ants monopolizing access to a greater proportion of the traps in low‐density arrays. Ordination reveals that regions and sampling‐intensity treatments could be discriminated and that differences between regions with different grazing histories were less apparent with high‐intensity sampling arrays than they were with low‐intensity sampling arrays. This suggests that differences between locations in space (or potentially samples in time) could be exaggerated by incomplete sampling of the patch‐scale fauna. Comparison of the present study with other studies suggests that most studies to date have used sampling intensities that would not give a thorough assessment of the patch‐scale ground‐dwelling fauna if sampled only by pit traps. The implications of the results for programmes of ant monitoring in rangelands are discussed.  相似文献   

16.
World-wide, diabetes is taking on epidemic proportions. This is a debilitating disease that damages and destroys bodily systems unless blood sugar levels are kept close to normal, and patients are therefore urged to practise attentive self-management. Among people with type II diabetes in Vietnam, such everyday attentiveness seems to far exceed clinical recommendations, suffusing daily lives in pervasive and yet elusive ways. Drawing on ethnographic fieldwork conducted in northern Vietnam, this article aims to depict the lifeworlds in which diabetes attentiveness unfolds. Seeking to capture the inchoate ways in which diabetes alters everyday lives, the article develops literary displacement as an experimental mode of writing-cum-inquiry that combines standard ethnography with ethnographic fiction. Taking diabetes in Vietnam as its case, the article shows how literary displacement can contribute to cultivating ethnographic as well as analytical sensibilities, strengthening the capacity of anthropology to capture subtle and subdued layers of life.  相似文献   

17.
Kemalism in Turkey is often presented as an exemplary case of paternalistic and authoritarian modernisation from above, and lauded or condemned for that very reason. Represented in these terms, certain analytic and political binaries are also activated: state versus society; world‐view versus life‐world; universality versus particularity; inauthenticity versus indigeneity; homogeneity versus heterogeneity/resistance. By contrast, in this paper I seek to sidestep these organising categories to focus on Kemalism and Islamism as rival forms of the same social imaginary signification, and not as shorthand for these polarities. Using a number of representative texts, I argue that the extravagance of Islamist resistance in Turkey post‐1980 brings to light the fantastical power of Kemalism itself, exposed as a project of the triumph of the will. This being the case, what has been written in anthropology about acts of ‘self‐institution’? The work of Nigel Rapport and Cornelius Castoriadis emphasises, in different ways, the arbitrariness and gratuity of social creation out of nothing or self‐institution. Pierre Bourdieu's work, on the other hand, is radically contrary to Rapport's in its structuralist elaboration of agency as guided action. My analysis of processes of change within both the Islamist and Republican social movements in Turkey from the early 1990s to the present seeks a temporary rapprochement, at least in this case, between Rapport's methodological individualism and Bourdieu's methodological holism.  相似文献   

18.
Variation in cranial robusticity among modern human populations is widely acknowledged but not well‐understood. While the use of “robust” cranial traits in hominin systematics and phylogeny suggests that these characters are strongly heritable, this hypothesis has not been tested. Alternatively, cranial robusticity may be a response to differences in diet/mastication or it may be an adaptation to cold, harsh environments. This study quantifies the distribution of cranial robusticity in 14 geographically widespread human populations, and correlates this variation with climatic variables, neutral genetic distances, cranial size, and cranial shape. With the exception of the occipital torus region, all traits were positively correlated with each other, suggesting that they should not be treated as individual characters. While males are more robust than females within each of the populations, among the independent variables (cranial shape, size, climate, and neutral genetic distances), only shape is significantly correlated with inter‐population differences in robusticity. Two‐block partial least‐squares analysis was used to explore the relationship between cranial shape (captured by three‐dimensional landmark data) and robusticity across individuals. Weak support was found for the hypothesis that robusticity was related to mastication as the shape associated with greater robusticity was similar to that described for groups that ate harder‐to‐process diets. Specifically, crania with more prognathic faces, expanded glabellar and occipital regions, and (slightly) longer skulls were more robust than those with rounder vaults and more orthognathic faces. However, groups with more mechanically demanding diets (hunter‐gatherers) were not always more robust than groups practicing some form of agriculture. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

19.
The mutational landscape model of adaptive sequence evolution has been used to explain an unexpected strong positive linear relationship between marginal fitness and mean site‐specific amino acid frequency in the functionally important HIV‐1 gp120 V3 protein region. The model predicts a positive linear relationship between the probability that a particular beneficial allele, among several, is the next to spread to fixation during an adaptive walk, its transition probability, and the allele's selection coefficient. Here, stochastic simulation is used to confirm the intuition that the linear relationship between transition probabilities and selection coefficients, predicted by the model, should, under fluctuating selection, produce a linear relationship between allele frequency, averaged across populations, and fitness. In addition, these relationships hold for the effective population size and mutation rate of HIV‐1 and for the moderately strong selection observed for V3. A survey of the strength of mutation for diverse organisms suggests that these relationships may be widely applicable.  相似文献   

20.
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