Resilience of rice (Oryzaspp.) pollen germination and tube growth to temperature stress

Resilience of rice cropping systems to potential global climate change will partly depend on temperature tolerance of pollen germination (PG) and tube growth (PTG). Germination of pollen of high temperature susceptible Oryza glaberrima Steud. (cv. CG14) and O. sativa L. ssp. indica (cv. IR64) and high temperature tolerant O. sativa ssp. aus (cv. N22), was assessed on a 5.6-45.4°C temperature gradient system. Mean maximum PG was 85% at 27°C with 1488 μm PTG at 25°C. The hypothesis that in each pollen grain, minimum temperature requirements (Tn) and maximum temperature limits (Tx) for germination operate independently was accepted by comparing multiplicative and subtractive probability models. The maximum temperature limit for PG in 50% of grains (Tx(50)) was lowest (29.8°C) in IR64 compared with CG14 (34.3°C) and N22 (35.6°C). Standard deviation (sx) of Tx was also low in IR64 (2.3°C) suggesting that the mechanism of IR64's susceptibility to high temperatures may relate to PG. Optimum germination temperatures and thermal times for 1mm PTG were not linked to tolerating high temperatures at anthesis. However, the parameters Tx(50) and sx in the germination model define new pragmatic criteria for successful and resilient PG, preferable to the more traditional cardinal (maximum and minimum) temperatures.

Age and firm growth: evidence from three European countries

This article provides new insights into the dependence of firm growth on age along the entire distribution of growth rates, and conditional on survival. Using data from the European firms in a global economy survey, and adopting a quantile regression approach, we uncover evidence for a sample of French, Italian and Spanish manufacturing firms with more than ten employees in the period from 2001 to 2008. We find that: (1) young firms grow faster than old firms, especially in the highest growth quantiles; (2) young firms face the same probability of declining as their older counterparts; (3) results are robust to the inclusion of other firms’ characteristics such as labor productivity, capital intensity and the financial structure; (4) high growth is associated with younger chief executive officers and other attributes that capture the attitude of the firm toward growth and change. The effect of age on firm growth is rather similar across countries.

The interface between organizational learning capability, entrepreneurial orientation, and SME growth

This paper investigates the interface between organizational learning capability, entrepreneurial orientation (EO), and small business performance. It reports on the findings from 350 small and medium enterprises (SMEs) in North Cyprus operating in the services and retailing sectors. The findings indicate a positive relationship between EO and sales and market share growth, but not between EO and employment growth. There is also a positive relationship between organizational learning capability and EO. This paper contributes to the small business management literature by providing a holistic analysis of the interface between organizational learning capability, EO, and growth.

Endothelin-1 and fibroblast growth factors stimulate the mitogen-activated protein kinase signaling cascade in cardiac myocytes. The potential role of the cascade in the integration of two signaling pathways leading to myocyte hypertrophy.

Maximally effective concentrations of endothelin-1 (ET-1), acidic FGF (aFGF), or 12-O-tetradecanoylphorbol-13-acetate (TPA) activated mitogen-activated protein kinase (MAPK) by 3-4-fold in crude extracts of myocytes cultured from neonatal rat heart ventricles. Maximal activation was achieved after 5 min. Thereafter, MAPK activity stimulated by ET-1 or aFGF declined to control values within 1-2 h, whereas activation by TPA was more sustained. Two peaks of MAPK activity (a 42- and a 44-kDa MAPK) were resolved in cells exposed to ET-1 or aFGF by fast protein liquid chromatography on a Mono Q column. One major and one minor peak of MAPK kinase (MAPKK) was stimulated by ET-1 or aFGF. Cardiac myocytes expressed protein kinase C (PKC)-alpha, -delta, -epsilon and -zeta as shown immunoblotting. Exposure to 1 microM TPA for 24 h down-regulated PKC-alpha, -delta, and -epsilon, but not PKC-zeta. This maneuver wholly abolished the activation of MAPK on re-exposure to TPA but did not affect the response to aFGF. The effect of ET-1 was partially down-regulated. ET-1 stimulated phospho[3H]inositide hydrolysis 18-fold, whereas aFGF stimulated by only 30%. Agonists which initially utilize dissimilar signaling pathways may therefore converge at the level of MAPKK/MAPK and this may be relevant to the hypertrophic response of the heart.

Finite-dimensional non-associative algebras and codimension growth

Let A be a (non-necessarily associative) finite-dimensional algebra over a field of characteristic zero. A quantitative estimate of the polynomial identities satisfied by A is achieved through the study of the asymptotics of the sequence of codimensions of A. It is well known that for such an algebra this sequence is exponentially bounded. Here we capture the exponential rate of growth of the sequence of codimensions for several classes of algebras including simple algebras with a special non-degenerate form, finite-dimensional Jordan or alternative algebras and many more. In all cases such rate of growth is integer and is explicitly related to the dimension of a subalgebra of A. One of the main tools of independent interest is the construction in the free non-associative algebra of multialternating polynomials satisfying special properties. (C) 2010 Elsevier Inc. All rights reserved.

Employment Protection Legislation and Firm Growth : Evidence from a Natural Experiment

A natural experiment is used to identify the causal relationship between employment protection legislation and fi…rm growth. The natural experiment occurred in Sweden in 2001, when an exemption made it possible for fi…rms with less than eleven employees to exclude two workers from the last-in-fi…rst-out principle when dismissing personnel. The estimated average treatment effect of the reform show that the number of employees increased with 0.135 percent in fi…rms with 5-9 employees relative to fi…rms with 10-15 employees, which corresponds to over 5,000 additional jobs per year created by the reform. Firms with ten employees, just below the size threshold, became 3.4 percent less likely to increase their workforce to a level surpassing the threshold, indicating that the last-in-…first-out rule prevented these …firms from growing. Thus, employment protection legislation seems to act as a growth barrier for small fi…rms.

The effects of Ikea and external shopping centers on regional trade and retail growth : A comparative analysis of Ikea’s establishment in Kalmar and Karlstad

This paper examines the effects of Ikea store establishment in Kalmar and Karlstad on the trade and retail inside the two cities, and as well on the trade and retail in the close neighboring municipalities and in further peripheral municipalities in both regions. After the establishment of Ikea store, Kalmar and Karlstad have experienced significant growth in trade and retail. The question, however, is how big this growth is in both cities? And how different locations on different distances from Ikea have been affected? What impact there was on different segments of the retail? How different business branches have been affected? How large the catchment area for the emerging new large-scale retail locations is? These questions, in addition to few others, are investigated in this paper. The thesis starts with an introduction chapter containing a background of the topic, problem description, the investigated questions, the purpose, and the outline of the paper. The next chapter includes the frame of reference which consists of literature review and theoretical framework about the external shopping centers and their impact on retail and regional trade development. It includes also information gathered from previous studies technical reports and other available sources about the subject. The third chapter includes description for the methods used to collect the primary and secondary data needed for the purpose of this study. Then the empirical framework which demonstrates the results of the conducted research followed by analysis and concluded in discussion and conclusion. Mixed methods are used as research strategy in this thesis, and the method to conduct the research is based on telephone interviews for the primary (qualitative) data, and documents and desk research for the secondary (quantitative) data. The gathered data is analyzed and designed in a way that allows the usage of comparative analysis technique to present the findings and draw conclusions. The results showed that new established Ikea retail store outside the city boundaries results with many effects on the city center and on the neighboring municipalities as well. The city center seems not to be affected negatively, but on the contrary positive effects were witnessed in both regions, these positive effects are linked to the increase inflow of customers from the external retail area which is known as spillover effect. III On the other hand, the neighboring towns and municipalities are more negatively affected especially with the trade of con-convenience goods as the consumers in these towns and municipalities start to go to the area of Ikea and the large external retail center to do their purchasing, the substitution effect is then said to be occurred. Moreover, the further far municipalities do not seem to be significantly affected by the establishment of Ikea. These effects whether positive or negative could be monitored by looking to few trade parameters such as the turnover, the sales index, and the consumers’ expenditure, these parameters can be very useful to measure the developments and changes in the trade and retail in a given place. 

A note on policy, the composition of public expenditures and economic growth

In this article we study the growth and welfare effects of fiscal and monetary policies in economies where public investment is part of the productive process we present four different models that share the same technology with public infrastructure as a separate argument of the production function. We show that growth is maximized at positive levels of income tax and inflation. However, unless there are no transfers or public goods in the economy, maximization of growth does not imply welfare maximization we show that the optimal tax rate is greater than the rate that maximizes growth and the optimal rate of money creation is below the growth maximizing rate. With public infrastructure in the production function we no longer obtain superneutrality in the Sidrausky model.

Inequality and economic growth in Latin

Latin America is the region that bears the highest rates of inequality in the world. Deininger and Squire (1996) showed that Latin American countries achieved only minor reductions in inequality between 1960 and 1990. On the other hand, East Asian countries, recurrently cited in recent literature on this issue, have significantly narrowed the gap in income inequality, while achieving sustained economic growth. These facts have triggered a renewed discussion on the relationship between income inequality and economic growth. According to the above literature, income inequality could have an adverse effect on countries’ growth rates. The main authors who spouse this line of thinking are Persson and Tebellini (1994), Alesina and Rodrik (1994), Perotti (1996), Bénabou (1996), and Deininger and Squire (1996, 1998). More recently, however, articles were published that questioned the evidence presented previously. Representatives of this new point of view, namely Li and Zou (1998), Barro (1999), Deininger and Olinto (2000) and Forbes (2000), believe that the relation between these variables can be positive, i.e., income inequality can indeed foster economic growth. Using this literature as a starting point, this article seeks to evaluate the relation between income inequality and economic growth in Latin America, based on a 13-country panel, from 1970 to 1995. After briefly reviewing the above articles, this study estimates the per capita GDP and growth rate equations, based on the neoclassical approach for economic growth. It also estimates the Kuznets curve for this sample of countries. Econometric results are in line with recent work conducted in this area – particularly Li and Zou (1998) and Forbes (2000) – and confirm the positive relation between inequality and growth, and also support Kuznets hypothesis.

Environmental protection and economic growth

This paper explores the link between environmental policy and economic growth by employing an extension of the AK Growth Model. We include a state equation for renewable natural resources. We assume that the change in environmental regulations induces costs and that economic agents also derive some utility from capital stock accumulation vis-`a-vis the environment. Using the Hopf bifurcation theorem, we show that cyclical environmental policy strategies are optimal, providing theoretical support for the Environmental Kuznets Curve.

Public investment in basic education and economic growth

The main objective of this paper was to visualize the relation between government spending on basic education and the human capital accumulation process, observing the impacts of this spending on individual investments in higher education, and on economic growth. It is used an overlapping-generations model where the government tax the adult generation and spent it in basic education of the next generations. It was demonstrated that the magnitude of the marginal effect of government spending in basic education on growth crucially depends on public budget constrains. The paper explains why some countries with a lot of public investment in basic education growth at low rates. In that sense if a country has only a lot of public investment in basic education without investment in higher education it may growth at low rates because the taxation can cause distortions in the agents incentives to invest in higher education.