Net Foreign Assets, Productivity and Real Exchange Rates in Constrained Economies

Empirical evidence suggests that real exchange rates (RER) behave differently in developed and developing countries. We develop an exogenous 2-sector growth model in which RER determination depends on the country's capacity to borrow from international capital markets. The country faces a constraint on capital inflows. With high domestic savings, the country converges to the world per capita income and RER only depends on productivity spread between sectors (Balassa-Samuelson effect). If the constraint is too tight and/or domestic savings too low, RER depends on both net foreign assets (transfer effect) and productivity. We then analyze the empirical implications of the model and find that, in accordance with the theory, RER is mainly driven by productivity and net foreign assets in constrained countries and exclusively by productivity in unconstrained countries.Real exchange rate; capital inflows constraint; overlapping generations

Efficiency and production frontiers in the aftermath of recessions: international evidence

The relationship between recessions and productivity growth has been the focus of an important body of theoretical and empirical research in the last two decades. We contribute to this literature by presenting new evidence on the evolution of productivity in the aftermath of recessions. Our method allows us to distinguish between frontier and (in-)efficiency effects of recessions. We present international evidence for a panel of 70 countries for the 1960-2000 period. Our results reveal that the average cumulative impact of recessions on productivity up to four years after its end is negative and significant. This, however, results from a mixture of mechanisms. The level of frontier production increases, but the rate of technical progress decreases, leading to a fall in frontier production. Efficiency also falls, lending support for the idea that recessions tend to reduce, rather than increase, economic restructuring. Long and deep recessions are also shown to have distinctive impacts on productivity

Identifying the Occurrence Time of the Destructive Kahramanmaraş-Gazientep Earthquake of Magnitude M7.8 in Turkey on 6 February 2023

Here, we employ natural time analysis of seismicity together with non-extensive statistical mechanics aiming at shortening the occurrence time window of the Kahramanmaraş-Gazientep M7.8 earthquake. The results obtained are in the positive direction pointing to the fact that after 3 February 2023 at 11:05:58 UTC, a strong earthquake was imminent. Natural time analysis also reveals a minimum fluctuation of the order parameter of seismicity almost three and a half months before the M7.8 earthquake, pointing to the initiation of seismic electrical activity. Moreover, before this earthquake occurrence, the detrended fluctuation analysis of the earthquake magnitude time-series reveals random behavior. Finally, when applying earthquake nowcasting, we find average earthquake potential score values which are compatible with those previously observed before strong (M≥7.1) earthquakes. The results obtained may improve our understanding of the physics of crustal phenomena that lead to strong earthquakes

A bio-inspired image coder with temporal scalability

We present a novel bio-inspired and dynamic coding scheme for static images. Our coder aims at reproducing the main steps of the visual stimulus processing in the mammalian retina taking into account its time behavior. The main novelty of this work is to show how to exploit the time behavior of the retina cells to ensure, in a simple way, scalability and bit allocation. To do so, our main source of inspiration will be the biologically plausible retina model called Virtual Retina. Following a similar structure, our model has two stages. The first stage is an image transform which is performed by the outer layers in the retina. Here it is modelled by filtering the image with a bank of difference of Gaussians with time-delays. The second stage is a time-dependent analog-to-digital conversion which is performed by the inner layers in the retina. Thanks to its conception, our coder enables scalability and bit allocation across time. Also, our decoded images do not show annoying artefacts such as ringing and block effects. As a whole, this article shows how to capture the main properties of a biological system, here the retina, in order to design a new efficient coder.Comment: 12 pages; Advanced Concepts for Intelligent Vision Systems (ACIVS 2011

Dry-reagent disposable dipstick test for visual screening of seven leukemia-related chromosomal translocations

We report the first dry-reagent, disposable, dipstick test for molecular screening of seven chromosomal translocations associated with acute and chronic leukemia. The dipstick assay offers about 10 times higher detectability than agarose gel electrophoresis and, contrary to electrophoresis, allows confirmation of the sequence of the polymerase chain reaction (PCR) product by hybridization within a few minutes without the need of instrumentation. Biotinylated amplified DNA is hybridized with a dA-tailed probe and applied to the strip, which contains oligo(dT)-conjugated gold nanoparticles in dry form. Upon immersion of the strip in the appropriate buffer, the solution migrates and the hybrids are captured by immobilized streptavidin at the test zone generating a characteristic red line. The excess nanoparticles are captured by oligo(dA) strands immobilized at the control zone of the strip producing a second red line. We studied the: t(9;22)(q34;q11), t(15;17)(q22;q21), t(11;17)(q23;q21), t(5;17)(q32;q21), t(11;17)(q13;q21), t(8,21)(q22;q22) and inv(16)(p13;q22) that generate the BCR-ABL, PML-RARa, PLZF-RARa, NPM-RARa, NuMA-RARa, AML1-ETO and CBFβ-MYH11 fusion genes, respectively. A single K562 cell was detectable amidst 10(6) normal leukocytes. A dipstick test was developed for actin, as a reference gene. The dipstick assay with appropriate probes can be used for identification of the fusion transcripts involved in the translocation

DFT insights into the electronic structure, mechanical behaviour, lattice dynamics and defect processes in the first Sc-based MAX phase Sc2SnC

Here we employed the density functional theory calculations to investigate some physical properties of first Sc-based MAX phase Sc(2)SnC including defect processes to compare with those of existing M(2)SnC phases. The calculated structural properties are in good agreement with the experimental values. The new phase Sc(2)SnC is structurally, mechanically and dynamically stable. Sc(2)SnC is metallic with a mixture of covalent and ionic character. The covalency of Sc(2)SnC including M(2)SnC is mostly controlled by the effective valence. Sc(2)SnC in M(2)SnC family ranks second in the scale of deformability and softness. The elastic anisotropy level in Sc(2)SnC is moderate compared to the other M(2)SnC phases. The hardness and melting point of Sc(2)SnC, including M(2)SnC, follows the trend of bulk modulus. Like other members of the M(2)SnC family, Sc(2)SnC has the potential to be etched into 2D MXenes and has the potential to be a thermal barrier coating material