On the Role of Imports in Enhancing Manufacturing Exports

Making use of a large panel data set on Italian manufacturing firms, we provide evidence on the effect of imports on the firm's export performance. We distinguish imports of intermediates according to their origin, and we find that inputs sourced from low labour cost countries promote the firm's export activity. Imports from high-income countries do not significantly contribute to the export orientation of firms, especially when both persistence in export and the possible endogeneity of the import measures are accounted for via system generalised method of moments (GMM) estimation of a linear probability model. Our evidence suggests that the impact of imports on the firms' export activity works through the cost-saving channel rather than the technology channel. © 2012 Blackwell Publishing Ltd

The plateau phase of growth of the L-M strain mouse cell in a protein-free medium : III. The effect of added glucose on protein and nucleic acid synthesis and on carborhydrate utilization

The addition of radioactive glucose to suspension cultures of L-M strain mouse cells during the plateau phase has been shown to extend the duration of this period from the normal 48-72 hr to 144-240 hr. Supplemental carbohydrate serves both as an energy source, as detected by the production of radioactive lactic acid and carbon dioxide, and as a precursor for nucleic acid and protein synthesis during this period. On the basis of the specific activities of the nucleic acids and proteins recovered from both the cells and the medium, possibilities of synthesis of multiple proteins and of extracellular RNA are discussed. The addition of radioactive homologous nucleic acidprotein fractions to culture in logarithmic growth is shown to reduce the mean generation time by 50 per cent. The recovery of 12 to 13 per cent of the radioactivity in these same fractions isolated from the cells at the end of logarithmic growth suggests that cells have the potential for re-utilization of cellular material release into the medium from other cells in the population.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32067/1/0000111.pd

Validation and benchmark of a novel low-cost measurement system of direct and diffuse irradiance at six sites worldwide

Direct normal irradiance (DNI) and diffuse horizontal irradiance (DHI) are important measurands to characterize atmospheric conditions. Several commercial measurement systems of DNI and DHI are available. Sun trackers with pyranometers and pyrheliometers are expensive and require constant maintenance due to their susceptibility to failures and soiling. Simpler, i.e. less expensive and more robust systems, that are commercially available, typically bring considerable deviations under certain atmospheric conditions. To meet such challenges, we developed PyranoCam, a novel measurement system for DNI, DHI and global horizontal irradiance (GHI). It consists of a pyranometer and an all-sky camera and uses a combined physical and machine-learning model. In our contribution we demonstrate PyranoCam's performance by a three-fold experimental campaign as follows. First, we validate PyranoCam at six sites around the world including various climates using sun trackers with ISO 9060:2018 Class A pyrheliometers and shaded pyranometers as references. PyranoCam exhibits competitive relative root mean square errors of 3.4% to 7.4% (DHI) and 2.1% to 4.5% (DNI) at all sites including four sites that were not used for training the model. Second, at two of the sites, we benchmark PyranoCam against three commercial systems (Rotating Shadowband Irradiometer, (RSI); Delta-T SPN1; EKO MS-90). PyranoCam is the most accurate system in the test. It is followed closely by the RSI. SPN1 and MS-90 show significant deviations. Third, by an extended measurement setup at one site, we investigate influences such as the spectral composition of GHI, DNI and DHI on the accuracy of each test system. The deviations of SPN1's DHI and DNI increase sharply in situations with high circumsolar irradiance. The MS-90's DNI errors strongly depend on the reference DNI. For RSP and PyranoCam, comparatively small deviations are found under all atmospheric conditions. In particular for PyranoCam, a high transferability between atmospheric conditions is indicated

Trade margins and exchange rate regimes: new evidence from a panel VAR

This paper studies how trade margins respond to output and terms of trade shocks in different exchange rate regimes within a panel of 23 OECD economies over the period 1988-2011. Using a panel VAR model, we confirm the predictions of entry models about the behaviour of export margins over the cycle. In addition, we find remarkable differences depending on the exchange rate regime. We document that fixed exchange rates have a positive effect on the extensive margin of trade in response to external shocks while flexible exchange rates have a pro-trade effect in response to output shocks. Our results imply that as long as extensive margins are a relevant portion of trade and external shocks are a major source of business cycle variability, the stabilization advantage of flexible exchange rates may be lower than previously thought

Comparative Transcriptome Analysis of Bacillus subtilis Responding to Dissolved Oxygen in Adenosine Fermentation

Dissolved oxygen (DO) is an important factor for adenosine fermentation. Our previous experiments have shown that low oxygen supply in the growth period was optimal for high adenosine yield. Herein, to better understand the link between oxygen supply and adenosine productivity in B. subtilis (ATCC21616), we sought to systematically explore the effect of DO on genetic regulation and metabolism through transcriptome analysis. The microarrays representing 4,106 genes were used to study temporal transcript profiles of B. subtilis fermentation in response to high oxygen supply (agitation 700 r/min) and low oxygen supply (agitation 450 r/min). The transcriptome data analysis revealed that low oxygen supply has three major effects on metabolism: enhance carbon metabolism (glucose metabolism, pyruvate metabolism and carbon overflow), inhibit degradation of nitrogen sources (glutamate family amino acids and xanthine) and purine synthesis. Inhibition of xanthine degradation was the reason that low oxygen supply enhanced adenosine production. These provide us with potential targets, which can be modified to achieve higher adenosine yield. Expression of genes involved in energy, cell type differentiation, protein synthesis was also influenced by oxygen supply. These results provided new insights into the relationship between oxygen supply and metabolism

Enhanced hydrogen production from thermochemical processes

To alleviate the pressing problem of greenhouse gas emissions, the development and deployment of sustainable energy technologies is necessary. One potentially viable approach for replacing fossil fuels is the development of a H2 economy. Not only can H2 be used to produce heat and electricity, it is also utilised in ammonia synthesis and hydrocracking. H2 is traditionally generated from thermochemical processes such as steam reforming of hydrocarbons and the water-gas-shift (WGS) reaction. However, these processes suffer from low H2 yields owing to their reversible nature. Removing H2 with membranes and/or extracting CO2 with solid sorbents in situ can overcome these issues by shifting the component equilibrium towards enhanced H2 production via Le Chatelier's principle. This can potentially result in reduced energy consumption, smaller reactor sizes and, therefore, lower capital costs. In light of this, a significant amount of work has been conducted over the past few decades to refine these processes through the development of novel materials and complex models. Here, we critically review the most recent developments in these studies, identify possible research gaps, and offer recommendations for future research

Phylogenetic and functional marker genes to study ammonia-oxidizing microorganisms (AOM) in the environment

The oxidation of ammonia plays a significant role in the transformation of fixed nitrogen in the global nitrogen cycle. Autotrophic ammonia oxidation is known in three groups of microorganisms. Aerobic ammonia-oxidizing bacteria and archaea convert ammonia into nitrite during nitrification. Anaerobic ammonia-oxidizing bacteria (anammox) oxidize ammonia using nitrite as electron acceptor and producing atmospheric dinitrogen. The isolation and cultivation of all three groups in the laboratory are quite problematic due to their slow growth rates, poor growth yields, unpredictable lag phases, and sensitivity to certain organic compounds. Culture-independent approaches have contributed importantly to our understanding of the diversity and distribution of these microorganisms in the environment. In this review, we present an overview of approaches that have been used for the molecular study of ammonia oxidizers and discuss their application in different environments