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1.
Despite high economic growth over the past 30 years, China's substantial and persistent regional disparities have been the subject of continuing concern to policy makers, as well as the target of a wide variety of policies. An important issue in the policy debate about whether and how best to attack these disparities is whether measures designed to improve regional equality come at a cost to national development, i.e., whether there is a trade‐off between the level of national output and the equality of its distribution across the regions. There is little analysis of this issue in the literature. We help fill this gap by setting up a two‐region model designed to capture some of the salient features of the Chinese economy. We subject this model to a number of policy shocks and assess the effects on regional disparities in per capita output, on the one hand, and on aggregate output on the other to investigate the trade‐off. We also consider income and welfare as alternatives to output. We find, first, that disparities in per capita output, income, and welfare may move in different directions so that it is important to specify which disparity is being targeted. Second, since both disparities and aggregate outcomes are endogenous, how they move together depends on the nature of the shock driving the model. Thus, some policies designed to reduce disparities face a trade‐off and others do not. Only a reduction in internal migration restrictions unambiguously reduces all three disparity measures and increases aggregate output, income, and welfare. All other policies considered face a trade‐off in at least one dimension. Third, whether there is a trade‐off depends also on the time horizon—some policies face a trade‐off in the short run and not in the long run and vice versa.  相似文献   

2.
The literature includes a number of reports, relating to both crop and non-crop species, showing conflicting responses of developmental plasticity to nitrogen availability. We reviewed 1130 papers published from 1990 to 2010 drawn from 14 agriculture-themed journals and conducted a critical appraisal of the effects of fertiliser nitrogen on time to heading or anthesis in barley and wheat, species for which there is a good deal of data. Features of the analysis were the use of relative responses (respect to unfertilised controls) of yield and time to flowering to nitrogen as a proxy for crop nitrogen status and developmental differences, respectively, and the standardisation of the start point for calculating time (in both calendar and thermal units) to flowering in autumn-sown winter cultivars to March 1 (N Hemisphere). The resulting database (180 cases) covered a broad range of unfertilised crop yields (1–8 Mg ha−1), and times to flowering (47–168 days). In very few cases (19 out of 118), the relative time to flowering in fertilised crops differed by more than 5% from those of unfertilised crops across a range of yield responses to fertiliser nitrogen from negligible to three-fold. Currently available evidence does not provide solid support to a plastic response of time to flowering to nitrogen in these two species.  相似文献   

3.
Cyberjaya is one of a long line of aspiring science and technology parks in the Asia‐Pacific region that have attempted to create a successful technopole, and in doing so become the ‘Silicon Valley of Asia’. The paper attends to the place‐making strategies through which Cyberjaya was positioned as a new ‘global hub’ for information communication technology and multimedia industries, framed as an extremely ‘sticky place’ (Markusen, 1996). That is, a place within a global economic system where local skills, infrastructure and capital attracts and makes research and development and corporate headquarters reluctant to leave. The paper considers that despite considerable infrastructural investment and state‐led urban boosterism to ‘sell’ Cyberjaya to prospective investors, more than 10 years after its completion in 1999 the development has become little more than a zone of disconnected business process outsourcing industries comprising low value‐added outsourcing activities.  相似文献   

4.
Increasing air temperature due to changing climate is projected to decrease the length of the growing season, hasten vegetative development and maturation, and ultimately affect yield of many C3 crops. Previous multilocation trials highlighted strong relationships between thermal trends in the interval “beginning of flowering‐end of grain filling” and grain yield, and protein content in durum wheat (Triticum turgidum subsp. durum (Desf.) Husn.). With the aim to confirm these relationships, nine durum wheat genotypes, including old (Capeiti 8, Senatore Cappelli and Trinakria) and modern (Amedeo, Arcangelo, Mongibello, Simeto, and Svevo) varieties and a Sicilian landrace (Russello) were grown at three different sites representing a climate gradient in Sicily, Italy. Moreover, the effect of post‐anthesis heat stress on these durum wheats was further investigated in two contrasting environments: open‐field (control—C) and greenhouse heat stress (HS). HS shortened the interval “beginning‐end of flowering” of 1.5 days across genotypes, and the “end of flowering‐beginning of grain filling” and maturation of 4.9 days, with a range of 1 day in Arcangelo to 11 days in Cappelli. Advances in main phenophases significantly decreased kernel weight (KW) and grain yield (GY), whereas grain protein content (PC) increased. As expected, a negative relationship was observed between GY and PC, while positive relationships were found for GY and grain‐filling duration (GFD), and GY and KW. Genotypes responded differently to heat stress, as evidenced by the net photosynthesis, transpiration rate, instantaneous water use efficiency and dry matter accumulation in kernels. Genotypes were ranked according to the heat susceptibility index (HSI): Amedeo, Arcangelo, Capeiti 8, Svevo and Trinakria resulted heat‐tolerant. These varieties were characterized by an early trigger of dry matter accumulation in kernels under HS (Amedeo, Arcangelo and Trinakria), or showed similar length of the GFD (Capeiti 8) between environments. The multilocation trial confirmed a negative relationship between maximum temperatures and grain yield, and a positive relationship between minimum temperatures and protein content during grain–filling periods. Research focusing on agronomic strategies, phenology and breeding for tolerance to heat stress is of strategic importance to cope with the detrimental effect of global warming in semi‐arid climates.  相似文献   

5.
This study analyzes three national department store chains in order to identify the factors most associated with their store closures. A binary logistic regression revealed some consistencies and differences in the associations. Larger stores are less likely to close for all three chains. Macy's and Sears stores are less likely to close in large malls (than freestanding stores) and if they are located in the West. J.C. Penney stores in the west are also less likely to close than in other regions, but stores in large shopping centers are more likely to close than freestanding stores. Store age was only significant for J.C. Penney stores, and indicated that older stores are more likely to close. Implications for retail managers and city economic vitality are mentioned and future research possibilities are discussed.  相似文献   

6.
The nucleotide-binding site (NBS)-leucine-rich repeat (LRR) gene family comprises the largest number of known disease resistance (R) genes and is one of the largest gene families in plants. In the present study, the full-length cDNA of ZmNL (GenBank Accession Number KF765443) was isolated using Rapid Amplification of cDNA Ends. The nucleotide sequence of ZmNL contains an open reading frame of 3156 bp that encodes the ZmNL protein, which is comprised of 1051 amino acid residues. This putative protein has high homology to other known resistance proteins (84% to Triticum aestivum LR10) and belongs to the CC–NBS–LRR type R gene family. The ZmNL gene was introduced into the maize inbred line of Huangzao4 which was highly susceptible to head smut under the control of the maize ubiquitin promoter by Agrobacterium-mediated transformation. The head smut disease incidence of 3 T2 transgenic lines was significantly reduced (by 18.38–29.40%) compared with the wild type, which indicated that the overexpression of ZmNL gene in maize enhanced the resistance to the fungus Sporisorium reilianum (Kühn) Clint of these plants.  相似文献   

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