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11.
When traditional methods for measuring economic welfare are scarce or unreliable, heights and BMIs are now well-accepted measurements that represent biological conditions during economic development. Weight, after controlling for height, is an additional measure for current net nutrition. Little is known about how weights varied among Mexicans living in the nineteenth century American West. Between 1870 and 1920, average Mexican weight was low and remained constant. Mexican farmers had the heaviest weights, and unskilled worker weights were low. Weight of Mexican-born individuals were higher than Mexicans born in the United States at low weights but lower at high weights. For combined characteristics, weight varied the most with age, an uncontrollable characteristic, indicating that nineteenth century Mexican current net nutrition varied the most with factors over which they had no control.  相似文献   
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Residential field courses are important and should be designed and delivered to maximize their value to students, staff and institutions. In this context, we use a novel approach involving analysis of the daily affective and conative reflections of students immersed in the field course experience to better understand student engagement with fieldwork. We show that students base their field course choice on a range of factors (costs and benefits) and that these choices subsequently influence student expectations and motivation to engage with fieldwork. We also show that the motivation of students to engage with fieldwork-based learning varies from person to person and from day to day. Our findings suggest that having a more nuanced understanding of the decisions students make when deciding which field course to enrol upon would enhance our ability to design attractive, accessible and useful field courses; that having an awareness of the expectations of students around field courses would enable us to better prepare them to undertake them; and that students are more motivated when they are afforded an opportunity to work independently and perceive themselves to have ownership of their learning.  相似文献   
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Despite its rich tradition, there are key limitations to researchers' ability to make generalizable inferences about state policy innovation and diffusion. This paper introduces new data and methods to move from empirical analyses of single policies to the analysis of comprehensive populations of policies and rigorously inferred diffusion networks. We have gathered policy adoption data appropriate for estimating policy innovativeness and tracing diffusion ties in a targeted manner (e.g., by policy domain, time period, or policy type) and extended the development of methods necessary to accurately and efficiently infer those ties. Our state policy innovation and diffusion (SPID) database includes 728 different policies coded by topic area. We provide an overview of this new dataset and illustrate two key uses: (i) static and dynamic innovativeness measures and (ii) latent diffusion networks that capture common pathways of diffusion between states across policies. The scope of the data allows us to compare patterns in both across policy topic areas. We conclude that these new resources will enable researchers to empirically investigate classes of questions that were difficult or impossible to study previously, but whose roots go back to the origins of the political science policy innovation and diffusion literature.  相似文献   
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In Scotland, the shooting industry has a significant impact on the economy, the environment and rural communities. However, styles of land management vary widely, and this is likely to have an effect on the benefits of shooting management. Here we construct a typology of management models, and test its utility in explaining economic benefits. Based on semi-structured interviews with 24 stakeholders representing 28 estates, three management models were defined: ‘Commercial Shooting Estates’ (CSE), ‘Non-commercial Shooting Estates’ (NSE) and ‘Diversified Estates’ (DE). DEs are differentiated from the other models as forestry, farming or biodiversity conservation, rather than shooting, is the main management objective. CSE and NSE are differentiated based on the degree of commercialisation of the shooting: CSEs let almost all of their shooting whereas NSEs do not let any shooting. Were the typology to be applied to a wider, systematic sample of estates, other factors may become more clearly differentiated. We found little variation between the three models in terms of spending and employment directly related to shooting activities. This study presents a typology of shooting management models that can be used to help identify pathways towards a new social contract between Scottish society and its landowners and managers.  相似文献   
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Communities living on remote islands are often viewed as among the most exposed and vulnerable to climate change impacts. This study uses the Sustainable Livelihoods Framework to investigate how indigenous communities living on two physically different islands in Torres Strait, Australia, experience what they consider to be the impacts of climate change in relation to their daily lives. During this process, a series of natural, physical, and socio‐cultural limits and barriers to climate change adaptation were identified on Boigu, a low‐lying mud island inundated by the sea during high tides and storm surges. As a volcanic island, Erub's elevation is higher but significant community infrastructure, housing, and cultural sites are located on the low coastal fringe. No immediate limits to climate change adaptation were identified on Erub, but physical and socio‐cultural barriers were revealed. Limits to climate change adaptation occur when adaptation actions fail to protect the things valued by those affected, or few adaptation options are available. Barriers to climate change adaptation may be overcome if recognised and addressed but can become entrenched limits if they are ignored. Within the participating communities, such limits and barriers included (a) restricted adaptation options due to limited access to particular livelihood assets; (b) difficulty engaging with government processes to secure external support; and (c) people's place‐based values, which evoke a reluctance to relocate or retreat.  相似文献   
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