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91.
商业秘密能够给权利人带来巨大的经济价值或竞争优势,因此要加强对商业秘密的保护,尤其是要加强对雇佣关系中的商业秘密的保护。在雇佣关系中,商业秘密权的保护与 择业自由权的保护存在着冲突,是保护商业秘密的难点。竞业禁止作为保护商业秘密的手段,同时存在于在职期间和离职后,雇主通常与雇员签订竞业禁止协议来保护商业秘密,如何确认竞业禁止协议的合法性、合理性问题是保护商业秘密的又一个难点。  相似文献   
92.
Knowledge of the ecology of Alliaria petiolata, an alien invasive species in the USA, is essential to predict the efficacy of introduced biological control agents. Accordingly, we examined the growth and reproduction of second‐year A. petiolata rosettes under natural and manipulated density regimes. Plant survival was also studied under natural conditions. Similar survivorship patterns were observed for high‐ and low‐density populations, although survival in the low‐density populations was c. 10% higher. Under natural conditions, low‐density plants were larger and more fecund, on average, than high‐density plants; however, on a per‐area basis, high‐density populations were much more productive. When plant density was experimentally reduced, average seed production and plant size increased with thinning intensity, suggesting that thinning released plants from intra‐specific competition. Additionally, plants in thinned plots were able to recover from past competition and could approach production of the plants in un‐thinned lower density plots that had not experienced prior competition. However, seed production per unit area was lower in thinned versus un‐thinned plots of the same initial density. Results suggest herbivore‐induced plant mortality late in the life cycle, as might occur following the introduction of biological control agents, may reduce the contribution to the A. petiolata seedbank.  相似文献   
93.
从国际竞争的高度研究中国先进生产力发展问题 ,探讨国际市场对中国先进生产力发展的作用及“入世”对中国发展的历史  相似文献   
94.
This study was conducted to investigate whether density, above-ground biomass and nitrogen (N) concentration of Cirsium arvense (L.) Scop. cause serious reductions in faba bean ( Vicia faba L.) yield. A 2-year field experiment (1991–93) with four Cirsium densities (0, 4, 16, 64 plants m–2) was carried out. Statistical analysis showed a significant effect of Cirsium density on faba bean yield. Multiple regression analysis showed that the main factors causing faba bean yield losses were the density and above-ground biomass of Cirsium . The results of this study demonstrate that Cirsium competition reduces faba bean yield. The mean faba bean yield losses over the 2 years were 10, 12 and 8% for above-ground biomass, seed and stem, respectively, for a Cirsium density of 16 plants m–2.  相似文献   
95.
分权化改革导致了地区间的竞争,地区间竞争有利于市场化,资源市场化流动在部分地区内可以促使政府改制的出现。但资源市场化流动还取决于其他客观条件,对于资源行政化流动和客观条件落后吸引不到资源的地区,政府则没有改制的动力,这解释了现实中改制与否两种情况并存的局面,而通过财政转移支付改进落后地区客观条件具有促进当地政府改制的作用。  相似文献   
96.
H. Vermeer 《Euphytica》1991,53(2):151-157
Summary A model for optimising single-stage and single-trait selection is presented. The model is based on the expected selection response model, extended with parameters describing the nature of the environment and with variables allowing a manipulation of selection schemes. As an example, the model is used to optimize tuber yield selection in potato breeding.Estimated parameter values have an uncertainty, which may bias the model outcome. Sensitivity analysis shows that the sensitivity to unrealistic parameter values for optimal allocation is less than the sensitivity for the selection response.  相似文献   
97.
Summary Pollen competition in vivo was studied by placing two pollen samples on one stigma and comparing the length of the tubes under a U.V. microscope. Comparisons involving pollen of Solanum tuberosum and S. phureja showed that 2x pollen grew faster than x pollen, both in 2x and x styles. Consequences for induction of dihaploids in S. tuberosum are discussed.  相似文献   
98.
J. Hill 《Plant Breeding》1993,110(3):212-219
Analysis of a half diallel cross among four white clover cultivars, grown as monocultures and in mixtures (duocultures) with two separate perennial rye-grass cultivars, confirmed that for stolon and leaf number a higher proportion of the genetic variance in duocultures was non-additive. For canopy height and dry weight, however, this proportion was less affected by inter-specific competition. An additive-dominance model of gene action sufficed for all four characters in monocultures, but in duocultures epis-tasis was just one of the factors complicating the genetic picture. This, coupled with short-term reversals in the direction of dominance, merely illustrates the complexity of breeding white clover cultivars. Possible future developments in the breeding of white clover are discussed in the light of these results.  相似文献   
99.
China's stock market enters a stage where the competition's rules as well as the competition's environment are changing continuously,Under such circumstances,to gain the competition advantages is of vital importarce to the existence and development of China's stock companies themselves. As a result, the stock companies should have a thorough analysis of the RBV theory at present, and evaluate its applicability to China's stock companies, Then they should come up with some reformational measures,aiming at improving the competition advantages of domestic stock companies. There fore they are able to make measonable use of the company's resources and accomplish the organic unity combination of the company's valued resources and its strategic administration. These are the key measures used by stock companies to gain the competition cedvantges.  相似文献   
100.
The impacts of nonindigenous species on native ecosystems can be severe, sometimes leading to the extinction of native taxa. Interspecific competition is a potential mechanism of negative impact of invasive species, but few studies have conclusively demonstrated competition between native and nonindigenous taxa. In this study I used experimental manipulations to examine the competitive effects of the larvae of two widely introduced anurans, the cane toad, Bufo marinus, and the Cuban treefrog, Osteopilus septentrionalis, on the growth and development of the larvae of two native anurans (the southern toad, Bufo terrestris, and the green treefrog, Hyla cinerea). The presence of O. septentrionalis larvae consistently impacted growth and development of native larvae, resulting in reduced growth rates and delayed metamorphosis of both native species and smaller mass at metamorphosis of B. terrestris. Hyla cinerea larvae transformed at greater body masses when reared with the rapidly transforming nonindigenous species as a result of competitive release. The negative effects of O. septentrionalis on native larvae were generally significant whether native tadpoles were exposed to O. septentrionalis alone or in combination with B. marinus. In contrast, B. marinus tadpoles did not significantly impact the growth or development of either native species. Neither nonindigenous species significantly decreased the survivorship of native larvae, although a trend toward decreased survivorship was evident for H. cinerea. These results suggest that nonindigenous larval anurans may adversely impact native tadpole communities as a result of interspecific competition.  相似文献   
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