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Recent scholarship has revised the once pessimistic view of the Chinese economy in the late 19th and early 20th centuries, but controversy surrounds the distribution effects of economic growth. Did livelihoods improve? Who benefited from the growth? Which regions were better off? Past studies infer an improved standard of living based on sparse data for wages, the output of cotton textiles and movements in grain prices. Height data provide an additional measure of the change in welfare, specifically the biological standard of living. This paper draws on the health examination records conducted at various Chinese government enterprises and agencies during the 1930s and 1940s, and shows a modest improvement in this measure of human welfare in some regions of China from the 1890s to the 1920s.  相似文献   

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Major disjunctions among marine communities in southeastern Australia have been well documented, although explanations for biogeographic structuring remain uncertain. Converging ocean currents, environmental gradients, and habitat discontinuities have been hypothesized as likely drivers of structuring in many species, although the extent to which species are affected appears largely dependent on specific life histories and ecologies. Understanding these relationships is critical to the management of native and invasive species, and the preservation of evolutionary processes that shape biodiversity in this region. In this study we test the direct influence of ocean currents on the genetic structure of a passive disperser across a major biogeographic barrier. Donax deltoides (Veneroida: Donacidae) is an intertidal, soft‐sediment mollusc and an ideal surrogate for testing this relationship, given its lack of habitat constraints in this region, and its immense dispersal potential driven by year‐long spawning and long‐lived planktonic larvae. We assessed allele frequencies at 10 polymorphic microsatellite loci across 11 sample locations spanning the barrier region and identified genetic structure consistent with the major ocean currents of southeastern Australia. Analysis of mitochondrial DNA sequence data indicated no evidence of genetic structuring, but signatures of a species range expansion corresponding with historical inundations of the Bassian Isthmus. Our results indicate that ocean currents are likely to be the most influential factor affecting the genetic structure of D. deltoides and a likely physical barrier for passive dispersing marine fauna generally in southeastern Australia.  相似文献   

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This paper illustrates the use of tree-ring indices as an indicator of economic stress. In the 19th century the rural economy in the Puna of Jujuy, Northwestern Argentina was based on livestock (llamas and sheep), and was heavily dependant on the availability of pasture and water in this arid landscape. In the absence of traditional indicators of socioeconomic stress, we used tree-ring indices from moisture sensitive trees (Juglans australis Griseb. and Polylepis tarapacana Phil.) as a proxy for droughts and their related economic stresses. Examining the relationship between population mortality and ring-width indices allows inferences to be drawn about the relative importance of environmental and sociopolitical factors in determining mortality patterns that contributed to the depopulation of this area in the late 19th century.  相似文献   

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Aim We deconstructed the mammal species richness pattern in Europe to assess the importance of large‐scale gradients in current macroclimate relative to biogeographic history, habitat heterogeneity and human influence (HHH variables) as richness determinants for total species, and for widespread and endemic species separately. Location Europe, west of 30° E. Methods We deconstructed total species richness (50‐km resolution) into its widespread and endemic species richness components. We used simultaneous autoregressive modelling (SAR) with information‐theoretic model selection and variation partitioning to assess the importance of macroclimate and HHH variables. The HHH variables included two historical factors, estimated by novel methodologies: (1) ice‐age‐driven dynamics, represented by accessibility to recolonization from hindcasting‐estimated glacial refugia, and (2) biogeographic peninsular dynamics, represented by distance to the entry region for the main European faunal source in western Asia. Results A large fraction of explained variation was shared between macroclimate and HHH in the SAR models. For total species richness, more variation could be uniquely attributed to macroclimate than to HHH, whereas for the deconstructed patterns (widespread and endemic species) the opposite was the case. Considering the individual factors, there was a strong peninsula effect on both widespread and endemic species richness but not on total richness. Main conclusions Both macroclimate and HHH variables (history, habitat heterogeneity and human influence) proved important predictors of species richness, but also difficult to disentangle. Notably, biogeographic history, in particular peninsular dynamics, is an important determinant of widespread and endemic species richness.  相似文献   

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The widespread production of cash crops can result in the decline of forests, peatlands, rice fields and local community land. Such unwanted land‐use and land‐cover (LULC) change can lead to decreased carbon stocks, diminished biodiversity, displaced communities and reduced local food production. In this study, we analysed to what extent four main commodities, namely, palm oil, pulpwood, rice and rubber, can be produced in North and East Kalimantan in Indonesia without such unwanted LULC change. We investigated the technical potential of four measures to mitigate unwanted LULC change between 2008 and 2020 under low, medium and high scenarios, referring to the intensities of the mitigation measures compared with those implemented in 2008. These measures are related to land sparing through (i) the improvements of yields, (ii) chain efficiencies, (iii) chain integration and (iv) the steering of any expansion of these commodities to suitable and available underutilised (potentially degraded) lands. Our analyses resulted in a land‐sparing potential of 0.4–1.2 Mha (i.e. 24–62% of the total land demand of the commodities) between 2008 and 2020, depending on the land‐use projection of the four commodities and the scenario for implementing the mitigation measures. Additional expansion on underutilised land is the most important mitigation measure (45–62% of the total potential), followed by yield improvements as the second most important mitigation measure (32–46% of the total potential). Our study shows that reconciling the production of palm oil, pulpwood, rice and rubber with the maintenance of existing agricultural lands, forests and peatlands is technically possible only (i) under a scenario of limited agricultural expansion, (ii) if responsible land zoning is applied and enforced and (iii) if the yields and chain efficiencies are strongly improved.  相似文献   

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A simple, rapid and sensitive chemiluminescent (CL) method for the assay of venlafaxine (VEN) in pharmaceutical formulations and serum samples by a two‐chip device is proposed. The method is based on the reaction of this drug with a tris(2,2′‐bipyridyl) ruthenium(II)–peroxydisulphate CL system. The optimum chemical conditions for CL emission were investigated. The calibration graph was linear for the concentration range 0.02–8.0 µg/mL. The detection and quantification limits were found to be 0.006 and 0.018 µg/mL, respectively, while the relative standard deviation (RSD) was <2.0%. The present CL procedure was applied to the determination of VEN in pharmaceutical formulations and serum samples; the recovery levels were in the range 96.5–101.2%. The results suggest that the method is unaffected by the presence of common formulation excipients found in these samples. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

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