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1.
Although existing studies questioned the simple positive correlation between the technology transfer speed and the benefits, they have been widely condemned for lacking empirical evidence. Using the patent transfer data at the city scale in China, and distinguishing fast from slow by dividing technology transfer speed into four levels, this paper attempts to answer the question in terms of city economic growth, which is whether the faster is the better. Panel regression results show that for economic growth of city, the speed of technology transfer does not mean that faster is better. In other words, technology transfer maintaining a relatively rapid speed (more than 1 year and less than 2 years) can promote city economic growth, although the evidence is weak.  相似文献   

2.
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   

3.
This paper highlights the evolution of the relations between highlanders and lowlanders that took place in one of the Mekong's riparian eastern territories in Ratanakiri province. It contributes to knowledge and debate on the impacts of landscape transformation and dispossession on indigenous peoples and their culture in upland Cambodia. The first section considers the legacy of the past and emphasises successive attempts of resistance. It contributes to an understanding of why highlanders opted to live in a forest milieu, not isolated from outsiders but careful to maintain some distance. The second section delineates the evolution of the interactions between natural ecosystems and social ecosystems in the changing tributary region. The last section documents major changes that have recently occurred under the guise of development. It questions the remaining possibilities for indigenous people to continue living with dignity in a shrunken territory in the present socio‐political environment. The conclusion proposes research orientations focusing on some neglected dimensions of indigenous cultures dealing with new forms of resistances.  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.
Elevated CO2 stimulates crop yields but leads to lower tissue and grain nitrogen concentrations [N], raising concerns about grain quality in cereals. To test whether N fertiliser application above optimum growth requirements can alleviate the decline in tissue [N], wheat was grown in a Free Air CO2 Enrichment facility in a low‐rainfall cropping system on high soil N. Crops were grown with and without addition of 50–60 kg N/ha in 12 growing environments created by supplemental irrigation and two sowing dates over 3 years. Elevated CO2 increased yield and biomass (on average by 25%) and decreased biomass [N] (3%–9%) and grain [N] (5%). Nitrogen uptake was greater (20%) in crops grown under elevated CO2. Additional N supply had no effect on yield and biomass, confirming high soil N. Small increases in [N] with N addition were insufficient to offset declines in grain [N] under elevated CO2. Instead, N application increased the [N] in straw and decreased N harvest index. The results suggest that conventional addition of N does not mitigate grain [N] depression under elevated CO2, and lend support to hypotheses that link decreases in crop [N] with biochemical limitations rather than N supply.  相似文献   

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