scholarly journals Convergence in Growth Rates: The Role of Capital Mobility and International Taxation

10.3386/w4214 ◽  
1992 ◽  
Author(s):  
Assaf Razin ◽  
Chi-Wa Yuen
Keyword(s):  
Growth Rates ◽  
Capital Mobility ◽  
International Taxation

scholarly journals Role of carbon allocation efficiency in the temperature dependence of autotroph growth rates

2018 ◽  
Vol 115 (31) ◽  
pp. E7361-E7368 ◽  
Author(s):  
Bernardo García-Carreras ◽  
Sofía Sal ◽  
Daniel Padfield ◽  
Dimitrios-Georgios Kontopoulos ◽  
Elvire Bestion ◽  
...  
Keyword(s):  
Growth Rate ◽  
Temperature Dependence ◽  
Growth Rates ◽  
Carbon Allocation ◽  
Thermal Sensitivity ◽  
Potential Growth ◽  
Allocation Efficiency ◽  
Population Growth Rates ◽  
Performance Curves

Relating the temperature dependence of photosynthetic biomass production to underlying metabolic rates in autotrophs is crucial for predicting the effects of climatic temperature fluctuations on the carbon balance of ecosystems. We present a mathematical model that links thermal performance curves (TPCs) of photosynthesis, respiration, and carbon allocation efficiency to the exponential growth rate of a population of photosynthetic autotroph cells. Using experiments with the green alga, Chlorella vulgaris, we apply the model to show that the temperature dependence of carbon allocation efficiency is key to understanding responses of growth rates to warming at both ecological and longer-term evolutionary timescales. Finally, we assemble a dataset of multiple terrestrial and aquatic autotroph species to show that the effects of temperature-dependent carbon allocation efficiency on potential growth rate TPCs are expected to be consistent across taxa. In particular, both the thermal sensitivity and the optimal temperature of growth rates are expected to change significantly due to temperature dependence of carbon allocation efficiency alone. Our study provides a foundation for understanding how the temperature dependence of carbon allocation determines how population growth rates respond to temperature.

scholarly journals Functional Ecology of Iceplant Taxa and Their Role in Eco-restoration of New Zealand Sand Dunes

2021 ◽  
Author(s):  
◽  
Guyo Duba Gufu
Keyword(s):  
New Zealand ◽  
Plant Species ◽  
Plant Communities ◽  
Growth Rates ◽  
Sand Dunes ◽  
Intergeneric Hybrid ◽  
Leaf Production ◽  
Natural Plant ◽  
Carpobrotus Edulis

<p>Biological invasion by non-native plant species has often been cited as a cause of native biodiversity loss. While the outcome of species invasions depends on interactions between exotic and resident native species, most studies of biological invasions have focused solely on the direct negative impacts of non-indigenous species on native biota. Although investigations of the role of competition in shaping natural plant communities were dominant in the previous generations and are still popular, more recent experimental research has uncovered the striking influence of facilitation on community dynamics. This thesis aims to investigate competitive and facilitative influence of the invasive South African iceplant (Carpobrotus edulis) on Spinifex sericeus, a native foredune grass species, with particular reference to implications of these interactions for dune restoration in New Zealand. It further explores the growth rates, substrate preferences and mating systems of the exotic and native iceplant taxa found in New Zealand. I begin by briefly outlining the influence of competition and facilitation on natural plant communities with reference to the role of facilitation in eco-restoration. I also give a few examples where exotic species have been found to facilitate native ones. Secondly, a neighbour removal experiment was conducted on coastal sand dunes with the main aim of studying the effects of Carpobrotus edulis on establishment of Spinifex sericeus at the foredune region. Finally, I compared the growth rates of the most widely distributed iceplant taxa in New Zealand in different substrates and the breeding systems of the exotic Carpobrotus.  Examples abound in literature of exotic plant species facilitating native ones especially in forestry. In the neighbour removal study, Carpobrotus edulis protected Spinifex seedlings against storm erosion, sandblasting and salt sprays while at the same time suppressing its leaf production. Suppression of Spinifex leaf production was more pronounced at top of the dune where stress elements is presumably more benign. There was no evidence of allelopathic suppression of Spinifex by C. edulis. Only Carpobrotus chilensis displayed some level of substrate preference by putting on relatively lower biomass in gravel. The exotic Carpobrotus spp. put on greater dry matter content than the native Disphyma australe and the Carpobrotus-x-Disphyma hybrid. The hybrid displayed a faster vegetative growth rate whereas D. australe allocated relatively more biomass to the roots than the shoot. Both Carpobrotus spp. are self compatible and highly capable of intrageneric and intergeneric hybridisation. Mass removal of the existing exotic iceplant stands from foredunes along high energy coasts is not advisable as they serve as useful stabilisers. The intergeneric hybrid is sexually sterile with sparsely spread stolons that could allow co-occurrence with other species and therefore is more suitable for foredune stabilisation. However, more research needs to be conducted on the ecology of the intergeneric hybrid.</p>

THE ROLE OF TRANSITORY AND PERSISTENT SHOCKS IN THE CONSUMPTION CORRELATION AND INTERNATIONAL COMOVEMENT PUZZLES

2013 ◽  
Vol 18 (6) ◽  
pp. 1234-1270 ◽  
Author(s):  
Tatsuma Wada
Keyword(s):  
Growth Rate ◽  
Learning Process ◽  
Productivity Growth ◽  
Growth Rates ◽  
Imperfect Information ◽  
Transitory Shocks ◽  
Technological Growth ◽  
No Consumption

We study a two-country model with changes in the technological growth rate. Such changes are attributed to transitory and persistent shocks in the growth rate of technology. Cases are considered in which agents in two countries do not have enough information to distinguish between the two types of shocks; gradually, however, the persistence of the shock is recognized through the learning process. Utilizing a set of parameters obtained from U.S. and European productivity growth rates, it is then shown that (i) when persistent shocks affect the two countries identically, there is no consumption-correlation puzzle, and the international comovement puzzle becomes imperceptible; and (ii) even when persistent shocks affect the two countries differently, imperfect information plays an important role in explaining both the consumption-correlation puzzle and the international comovement puzzle (provided transitory shocks are strongly internationally correlated and are relatively larger than persistent shocks).

E-Government Practices in Regional Context

2008 ◽  
pp. 2771-2790
Author(s):  
Derya Altunbas ◽  
Elif Tosun
Keyword(s):  
Regional Development ◽  
Information And Communication Technologies ◽  
Growth Rates ◽  
Communication Technologies ◽  
Development Programs ◽  
Government Programs ◽  
Socioeconomic Transformation ◽  
National Economic ◽  
Information And Communication

This chapter introduces the importance of the Information and Communication Technologies on the regional development in Turkey. Socioeconomic transformation can be done with the efficient service opportunities in regions that have different growth rates. Specially, some regions have migration problems for economic and employment reasons in Turkey. Growth poles are a typical development style for Turkey. Therefore, less developed regions should have more advantage from national economic programs. In this chapter, included in Regional development programs of Turkey in the context of Information and Communication Technologies. The objective of this chapter is to point out importance of improvements of Information and Communication Technologies and e-government programs in Turkey. At this time, it is defined the role of e-government programs on social, economic and political structures of the regions in Turkey.

scholarly journals The role of coccoliths in protecting <i>Emiliania huxleyi</i> against stressful light and UV radiation

2016 ◽  
Vol 13 (16) ◽  
pp. 4637-4643 ◽  
Author(s):  
Juntian Xu ◽  
Lennart T. Bach ◽  
Kai G. Schulz ◽  
Wenyan Zhao ◽  
Kunshan Gao ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Uv Radiation ◽  
Growth Rates ◽  
Emiliania Huxleyi ◽  
Photochemical Quenching ◽  
Visible Radiation ◽  
Light Levels ◽  
Relative Electron ◽  
Non Photochemical Quenching

Abstract. Coccolithophores are a group of phytoplankton species which cover themselves with small scales (coccoliths) made of calcium carbonate (CaCO3). The reason why coccolithophores form these calcite platelets has been a matter of debate for decades but has remained elusive so far. One hypothesis is that they play a role in light or UV protection, especially in surface dwelling species like Emiliania huxleyi, which can tolerate exceptionally high levels of solar radiation. In this study, we tested this hypothesis by culturing a calcified and a naked strain under different light conditions with and without UV radiation. The coccoliths of E. huxleyi reduced the transmission of visible radiation (400–700 nm) by 7.5 %, that of UV-A (315–400 nm) by 14.1 % and that of UV-B (280–315 nm) by 18.4 %. Growth rates of the calcified strain (PML B92/11) were about 2 times higher than those of the naked strain (CCMP 2090) under indoor constant light levels in the absence of UV radiation. When exposed to outdoor conditions (fluctuating sunlight with UV radiation), growth rates of calcified cells were almost 3.5 times higher compared to naked cells. Furthermore, the relative electron transport rate was 114 % higher and non-photochemical quenching (NPQ) was 281 % higher in the calcified compared to the naked strain, implying higher energy transfer associated with higher NPQ in the presence of calcification. When exposed to natural solar radiation including UV radiation, the maximal quantum yield of photosystem II was only slightly reduced in the calcified strain but strongly reduced in the naked strain. Our results reveal an important role of coccoliths in mitigating light and UV stress in E. huxleyi.

Relationship between some Staphylococcus aureus pathogenic factors and growth rates and somatic cell counts

2005 ◽  
Vol 72 (2) ◽  
pp. 203-208 ◽  
Author(s):  
Alfonso Zecconi ◽  
Enrica Binda ◽  
Vitaliano Borromeo ◽  
Renata Piccinini
Keyword(s):  
Growth Rate ◽  
Inflammatory Response ◽  
Growth Rates ◽  
Protein Gene ◽  
The Other ◽  
Staph Aureus ◽  
Pathogenic Factors ◽  
Binding Protein Gene ◽  
The One

Staphylococcus aureus isolates produce several pathogenic factors. The combination of these products influences the pathogenic role of different isolates, but their specific effects are well known in the pathogenesis of udder infections. This study focused on the association of polymorphism of the coagulase gene, protein A gene, collagen-binding protein gene, and of fibrinogen-binding protein gene on somatic cell count (SCC) and on Staph. aureus growth rate. Fifty Staph. aureus isolates from 13 dairy cow herds, located in seven different provinces, were considered. The results showed a low frequency of cna gene, similar to the one observed in human isolates. Meanwhile, the high frequency of efb gene indirectly confirmed the role of this factor in bacterial pathogenesis, being associated with adhesion to epithelia. The association of these two single genes with SCC and growth rate showed to be not significant. The polymorphism of spa gene was confirmed to be significantly associated with inflammatory response and growth rate, albeit with a pattern different from the one suggested for human isolates. Sorting of isolates based on the clusters obtained by combining polymorphisms of spa and coa genes and the presence of cna and efb genes, showed that a single cluster (cluster V) was prevalent in the different herds and provinces, while the other six clusters identified were widely spread among the remaining 60% of the isolates. Results showed that clusters VI and VII had significantly higher growth rates at 3, 4, and 6 h in comparison with the other clusters. Meanwhile, quarters infected with these strains showed significantly lower SCC levels. The frequency of isolates from cluster V, suggested that they should possess pathogenic factors increasing their invasiveness, even if in the presence of a stronger inflammatory response. These results indirectly confirm previous findings on the different interactions between isolates and the udder immune system. They also suggest that isolates with higher growth rates and inducing a lower inflammatory response have better chances to spread among the herd. The relatively simple genomic method proposed in this study could be applied by an increasing number of diagnostic laboratories and could be useful in studying the epidemiology of Staph. aureus intramammary infections in dairy herds when collecting data from the field.

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