Factor Proportions and the Growth of World Trade

Most of the expansion of global trade during the last three decades has been of the North-South kind - between capital-abundant developed and labour-abundant developing countries. Based on this observation, I argue that the recent growth of world trade is best understood from a factor-proportions perspective. I present novel evidence documenting that differences in capital-labour ratios across countries have increased in the wake of two shocks to the global economy: i) the opening up of China and ii) financial globalisation and the resulting upstream capital flows towards capital-abundant regions. I analyse their impact on specialisation and the volume of trade in a dynamic model which combines factor-proportions trade in goods with international trade in financial assets. Calibrating this model, I find that it can account for 60% of world trade growth between 1980 and 2007. It is also capable of predicting international investment patterns which are consistent with the data

The international trade as the sole engine of growth for an economy

Can international trade act as the sole engine of growth for an economy? If yes, what are the mechanisms through which trade operates in transmitting permanent growth? This paper answers these questions with two simple two-country models, in which only one country enjoys sustained growth in autarky. The models differ in the assumptions on technical change, which is either labour- or capital-augmenting. In both cases, the stagnant economy imports growth by trading. In the first model, growth is transmitted because of permanent increases in the trade volume. In the alternative framework, the stagnant economy imports sustained growth because its terms of trade permanently improve.

Comparative studies on the growth and reproductive performances of Rhodnius prolixus reared on different blood sources

Host blood source was found to affect both the development and the reproductive performance of Rhodnius prolixus. The insects were reared on citrated human, rabbit, chicken, sheep and horse blood sources, through a membrane feeder, during an entire life cycle, from eggs to adults. Development and reproduction in terms of the number of unfed insects, number of moulting, mortality intermoulting period, number of egg/female, conversion of blood into egg (mg meal/egg) and percentage of hatch as effective physiological parameters were investigated. Our results showed that human or rabbit blood meals were more nutritionally efficient than the other blood samples used because (i) the insects developed faster, presented low mortality and about 80% of them reached the adult stage; and (ii) females oviposited an average of at least 100% more eggs. The inefficiency of chicken and horse blood sources as diets for R. prolixus was manifested in (i) a decrease of the amount of ingested blood and (ii) only a reasonable nutritional quality. The inadequacy of sheep blood was observed by a mortality extremely high, poor moulting response and drastic reduction in egg production.

The Growth in Inter-connectedness in the Scottish Economy 1998-2007; a disaggregated analysis.

The measurement of inter-connectedness in an economy using input-output tables is not new, however much of the previous literature has not had any explicit dynamic dimension. Studies have tried to estimate the degree of inter-relatedness for an economy at a given point in time using one input-output table, some have compared different economies at a point in time but few have looked at the question of how interconnectedness within an economy changes over time. The publication in 2010 of a consistent series of input-output tables for Scotland offers the researcher the opportunity to track changes in the degree of inter-connectedness over the seven year period 1998 to 2007. The paper is in two parts. A simple measure of inter-connectedness is introduced in the first part of the paper and applied to the Scottish tables. In the second part of the paper an extraction method is applied to sector by sector to the tables in order to estimate how interconnectedness has changed over time for each industrial sector.

The Emperor Has New Clothes: Empirical Tests of Mainstream Theories of Economic Growth

Modern macroeconomic theory utilises optimal control techniques to model the maximisation of individual well-being using a lifetime utility function. Agents face choices over current and future consumption (with resultant implied savings decisions) seeking to maximise the present value of current plus future well-being. However, such inter-temporal welfare-maximising assumptions remain empirically untested. In the work presented here we test whether welfare was in (historical) fact maximised in the US between 1870-2000 and find empirical support for the optimising basis of growth theory, but only once a comprehensive view of what constitutes a country’s wealth or capital is taken into account.

Nowcasting Scottish GDP Growth

The delays in the release of macroeconomic variables such as GDP mean that policymakers do not know their current values. Thus, nowcasts, which are estimates of current values of macroeconomic variables, are becoming increasingly popular. This paper takes up the challenge of nowcasting Scottish GDP growth. Nowcasting in Scotland, currently a government office region within the United Kingdom, is complicated due to data limitations. For instance, key nowcast predictors such as industrial production are unavailable. Accordingly, we use data on some non-traditional variables and investigate whether UK aggregates can help nowcast Scottish GDP growth. Such data limitations are shared by many other sub-national regions, so we hope this paper can provide lessons for other regions interested in developing nowcasting models.

Are the high-growth recovery periods over?

We present evidence about the loss of the so-called "plucking effect", that is, a high-growth phase of the cycle typically observed at the end of recessions. This result matches the popular belief, presented informally by different authors, that the current recession will have permanent effects, or that the current recession will have an L shape versus the old-time recessions that have always had a V shape. Furthermore, we show that the loss of the "plucking effect" can explain part of the Great Moderation. We postulate that these two phenomena may be due to changes in inventory management brought about by improvements in information and communications technologies.

Asynchronous growth and competition in a two-sex age-structured population model

Asynchronous exponential growth has been extensively studied in population dynamics. In this paper we find out the asymptotic behaviour in a non-linear age-dependent model which takes into account sexual reproduction interactions. The main feature of our model is that the non-linear process converges to a linear one as the solution becomes large, so that the population undergoes asynchronous growth. The steady states analysis and the corresponding stability analysis are completely made and are summarized in a bifurcation diagram according to the parameter R0. Furthermore the effect of intraspecific competition is taken into account, leading to complex dynamics around steady states.

A two-sector growth model with institutional saving and investment

This paper develops a two-sector growth model in which institutional investors play a significant role. A necessary and sufficient condition is established under which these investors own the entire capital stock in the long run. The dependence of the long-run growth rate on the behaviour of such investors, and the effects of a productivity increase are analysed.

Coloration signals the ability to cope with elevated stress hormones: effects of corticosterone on growth of barn owls are associated with melanism.

Stressful situations during development can shape the phenotype for life by provoking a trade-off between development and survival. Stress hormones, mainly glucocorticoids, play an important orchestrating role in this trade-off. Hence, how stress sensitive an animal is critically determines the phenotype and ultimately fitness. In several species, darker eumelanic individuals are less sensitive to stressful conditions than less eumelanic conspecifics, which may be due to the pleiotropic effects of genes affecting both coloration and physiological traits. We experimentally tested whether the degree of melanin-based coloration is associated with the sensitivity to an endocrine response to stressful situations in the barn owl. We artificially administered the mediator of a hormonal stress response, corticosterone, to nestlings to examine the prediction that corticosterone-induced reduction in growth rate is more pronounced in light eumelanic nestlings than in darker nest mates. To examine whether such an effect may be genetically determined, we swapped hatchlings between randomly chosen pairs of nests. We first showed that corticosterone affects growth and, thus, shapes the phenotype. Second, we found that under corticosterone administration, nestlings with large black spots grew better than nestlings with small black spots. As in the barn owl the expression of eumelanin-based coloration is heritable and not sensitive to environmental conditions, it is therefore a reliable, genetically based sign of the ability to cope with an increase in blood corticosterone level.

Outcome of Patients with Platelet-Derived Growth Factor Receptor Alpha-Mutated Gastrointestinal Stromal Tumors in the Tyrosine Kinase Inhibitor Era.

PURPOSE: Platelet-derived growth factor receptor-alpha (PDGFRA) mutations are found in approximately 5% to 7% of advanced gastrointestinal stromal tumors (GIST). We sought to extensively assess the activity of imatinib in this subgroup. EXPERIMENTAL DESIGN: We conducted an international survey among GIST referral centers to collect clinical data on patients with advanced PDGFRA-mutant GISTs treated with imatinib for advanced disease. RESULTS: Fifty-eight patients were included, 34 were male (59%), and median age at treatment initiation was 61 (range, 19-83) years. The primary tumor was gastric in 40 cases (69%). Thirty-two patients (55%) had PDGFRA-D842V substitutions whereas 17 (29%) had mutations affecting other codons of exon 18, and nine patients (16%) had mutation in other exons. Fifty-seven patients were evaluable for response, two (4%) had a complete response, eight (14%) had a partial response, and 23 (40%) had stable disease. None of 31 evaluable patients with D842V substitution had a response, whereas 21 of 31 (68%) had progression as their best response. Median progression-free survival was 2.8 [95% confidence interval (CI), 2.6-3.2] months for patients with D842V substitution and 28.5 months (95% CI, 5.4-51.6) for patients with other PDGFRA mutations. With 46 months of follow-up, median overall survival was 14.7 months for patients with D842V substitutions and was not reached for patients with non-D842V mutations. CONCLUSIONS: This study is the largest reported to date on patients with advanced PDGFRA-mutant GISTs treated with imatinib. Our data confirm that imatinib has little efficacy in the subgroup of patients with D842V substitution in exon 18, whereas other mutations appear to be sensitive to imatinib. Clin Cancer Res; 18(16); 4458-64. ©2012 AACR.

Small firms, growth and financial constraints

This paper analyses the impact of different sources of finance on the growth of firms. Using panel data from Spanish manufacturing firms for the period 2000-2006, we investigate the effects of internal and external finances on firm growth. In particular, we examine three dimensions of these financial sources: a) the performance of the firms’ capital structure in accordance with firm size; b) the effects of internal and external financial sources on growth performance; c) the combined effect of equity, external debt and cash flow on firm growth. We find that low-growth firms are sensitive to cash flow and short-term bank debt, while high-growth firms are more sensitive to long-term debt. Furthermore, equity capital seems to reduce barriers to external finance. Our main conclusion is that during the start-up phase, firms are unable to increase their financial leverage and so their capital structure fails to promote correct investment strategies. However, as their equity capital increases, alternative financial mechanisms, in particular long-term debt, become available, which have a positive impact on firm growth.

Drosophila Myc interacts with host cell factor (dHCF) to activate transcription and control growth.

The Myc proto-oncoproteins are transcription factors that recognize numerous target genes through hexameric DNA sequences called E-boxes. The mechanism by which they then activate the expression of these targets is still under debate. Here, we use an RNAi screen in Drosophila S2 cells to identify Drosophila host cell factor (dHCF) as a novel co-factor for Myc that is functionally required for the activation of a Myc-dependent reporter construct. dHCF is also essential for the full activation of endogenous Myc target genes in S2 cells, and for the ability of Myc to promote growth in vivo. Myc and dHCF physically interact, and they colocalize on common target genes. Furthermore, down-regulation of dHCF-associated histone acetyltransferase and histone methyltransferase complexes in vivo interferes with the Myc biological activities. We therefore propose that dHCF recruits such chromatin-modifying complexes and thereby contributes to the expression of Myc targets and hence to the execution of Myc biological activities.

Phytochrome interacting factors 4 and 5 control seedling growth in changing light conditions by directly controlling auxin signaling.

Plant growth is strongly influenced by the presence of neighbors that compete for light resources. In response to vegetational shading shade-intolerant plants such as Arabidopsis display a suite of developmental responses known as the shade-avoidance syndrome (SAS). The phytochrome B (phyB) photoreceptor is the major light sensor to mediate this adaptive response. Control of the SAS occurs in part with phyB, which controls protein abundance of phytochrome-interacting factors 4 and 5 (PIF4 and PIF5) directly. The shade-avoidance response also requires rapid biosynthesis of auxin and its transport to promote elongation growth. The identification of genome-wide PIF5-binding sites during shade avoidance revealed that this bHLH transcription factor regulates the expression of a subset of previously identified SAS genes. Moreover our study suggests that PIF4 and PIF5 regulate elongation growth by controlling directly the expression of genes that code for auxin biosynthesis and auxin signaling components.