Foreign direct investment and trade: complements or substitutes?

This paper examines the relationship between international production and exports for a number of countries. In the theoretical literature the relationship between direct investment and trade is not certain apriori: some works emphasize their complementarity, others their reciprocal substitutability, depending on the aim of the investment (e.g. to serve the local market, to transfer production phases to low-wage countries, to circumvent trade barriers, to acquire natural or technological resources). The empirical investigation performed finds that the hypothesis of complementarity is more robust than that of substitutability, albeit with pronounced differences between areas. A panel econometric analysis of an “enlarged” gravitational model, performed on the markets of five industrial countries for the period 1985-94, shows that the imports of market i from country j are positively correlated with the sales of the foreign affiliates of country j that are present in market i, after controlling for the effect of the ordinary variables of scale, economic similarity and relative distance. However, an alternative analysis, using appropriate “indices of relative geographical orientation” constructed for the exports and direct investment flows of the leading investor countries towards the main areas of the world in 1982-94, shows that the complementarity hypothesis is not confirmed in equal measure for all the flows examined. In particular, complementarity is greater for flows between the United States and the European Union than for those between European countries and those between North America and Japan, where a possible substitution of direct investment for exports is found.direct investment, trade

Controlling a Van Hove singularity and Fermi surface topology at a complex oxide heterostructure interface.

The emergence of saddle-point Van Hove singularities (VHSs) in the density of states, accompanied by a change in Fermi surface topology, Lifshitz transition, constitutes an ideal ground for the emergence of different electronic phenomena, such as superconductivity, pseudo-gap, magnetism, and density waves. However, in most materials the Fermi level, [Formula: see text], is too far from the VHS where the change of electronic topology takes place, making it difficult to reach with standard chemical doping or gating techniques. Here, we demonstrate that this scenario can be realized at the interface between a Mott insulator and a band insulator as a result of quantum confinement and correlation enhancement, and easily tuned by fine control of layer thickness and orbital occupancy. These results provide a tunable pathway for Fermi surface topology and VHS engineering of electronic phases

Enhanced osteogenic differentiation in zoledronate-treated osteoporotic patients

Bisphosphonates are well known inhibitors of osteoclast activity and thus may be employed to influence osteoblast activity. The present study was designed to evaluate the in vivo effects of zoledronic acid (ZA) on the proliferation and osteoblastic commitment of mesenchymal stem cells (MSC) in osteoporotic patients. We studied 22 postmenopausal osteoporotic patients. Densitometric, biochemical, cellular and molecular data were collected before as well as after 6 and 12 months of ZA treatment. Peripheral blood MSC-like cells were quantified by colony-forming unit fibroblastic assay; their osteogenic differentiation potential was evaluated after 3 and 7 days of induction, respectively. Circulating MSCs showed significantly increased expression levels of osteoblastic marker genes such as Runt-related transcription factor 2 (RUNX2), and Osteonectin (SPARC) during the 12 months of monitoring time. Lumbar bone mineral density (BMD) variation and SPARC gene expression correlated positively. Bone turnover marker levels were significantly lowered after ZA treatment; the effect was more pronounced for C terminal telopeptide (CTX) than for Procollagen Type 1 N-Terminal Propeptide (P1NP) and bone alkaline phosphatase (bALP). Our findings suggest a discrete anabolic activity supported by osteogenic commitment of MSCs, consequent to ZA treatment. We confirm its anabolic effects in vivo on osteogenic precursors

Importancia de mencionar las porciones en las características de intervención dietética para poder extrapolar el estudio en distintos medios

[email protected] al editorRevisión por pare

Observation of a flat and extended surface state in a topological semimetal

A topological flatband, also known as drumhead states, is an ideal platform to drive new exotic topological quantum phases. Using angle-resolved photoemission spectroscopy experiments, we reveal the emergence of a highly localized possible drumhead surface state in a topological semimetal BaAl4 and provide its full energy and momentum space topology. We find that the observed surface state is highly localized in momentum, inside a square-shaped bulk Dirac nodal loop, and in energy, leading to a flat band and a peak in the density of state. These results establish this class of materials as a possible experimental realization of drumhead surface states and provide an important reference for future studies of fundamental physics of topological quantum phase transition

Public Engagement Provides First Insights on Po Plain Ant Communities and Reveals the Ubiquity of the Cryptic Species Tetramorium immigrans (Hymenoptera, Formicidae)

Ants are considered a useful model for biodiversity monitoring and several of their characteristics make them promising for citizen science (CS) projects. Involving a wide range of public figures into collecting valuable data on the effect of human impact on ant biodiversity, the School of Ants (SoA) project represents one of the very few attempts to explore the potential of these insects in CS. Through the collaboration with the "BioBlitz Lombardia" project, we tested the SoA protocol on 12 Northern Italy parks, ranging from urban green to subalpine protected sites. As a result, we obtained some of the very first quantitative data characterizing the ants of this region, recording 30 species and highlighting some interesting ecological patterns. These data revealed the ubiquitous presence of the recently taxonomically defined cryptic species Tetramorium immigrans, which appears to be probably introduced in the region. We also discuss advantages and criticisms encountered applying the SoA protocol, originally intended for schools, to new categories of volunteers, from BioBlitz participants to park operators, suggesting best practices based on our experience