Debt Intolerance

This paper introduces the concept of "debt intolerance," which manifests itself in the extreme duress many emerging market economies experience at levels of indebtedness that would seem manageable by advanced country standards. The paper argues that "safe" external debt-to-GNP thresholds for debt-intolerant countries depend on the country's default and inflation history and may be as low as 15 percent in some cases. Debt intolerance is linked to the phenomenon of serial default that has plagued many countries over the past two centuries. Understanding and measuring debt intolerance is fundamental to assessing the problems of debt sustainability, debt restructuring, capital market integration, and the scope for international lending to ameliorate crises. The paper makes a first pass at quantifying debt intolerance, including delineating debtors' "clubs" and regions of vulnerability, based on a history of credit events for a large number of countries going back to the 1820s.macroeconomics, Debt Intolerance

Addicted to Dollars

Dollarization, in a broad sense, is increasingly a defining characteristic of many emerging market economies. How important is this trend quantitatively and how important is it for the conduct of monetary policy and the choice of exchange rate regimes? Though these questions have become a hot topic in both the theory and policy literature, most efforts are remarkably uninformed by evidence, in no small part because meaningful data has been lacking, except for a very narrow range of assets. This paper attempts to move the discussion forward and shed light on the critical questions by proposing a measure of dollarization that is broad both conceptually and in terms of country coverage. We use this measure to identify trends in the evolution of dollarization in the developing world in the last two decades, and to ascertain the consequences that dollarization has had on the effectiveness of monetary and exchange rate policy. We find that, contrary to the general presumption in the literature, a high degree of dollarization does not seem to be an obstacle to monetary control or to disinflation. A level of dollarization does, however, appear to increase exchange rate pass-through, reinforcing the claim that fear of floating' is a greater problem for highly dollarized economies. We also review the developing countries' record in combating their addiction to dollars. Concretely, we try to explain why some countries have been able to avoid certain forms of the addiction, and examine the evidence on successful de-dollarization.

Retromode imaging modality of epiretinal membranes

(1) Purpose: To determine the characteristics of macular epiretinal membranes (ERM) using non-invasive retromode imaging (RMI) and to compare retromode images with those acquired via fundus autofluorescence (FAF) and fundus photography. (2) Methods: Prospective observational case-series study including patients with macular ERM with no other ocular disease affecting their morphology and/or imaging quality. We compared RMI, FAF and fundus photography features by cropping and overlapping images to obtain topographic correspondence. (3) Results: In total, 21 eyes (21 patients) affected by ERM were included in this study. The mean area of retinal folds detected by RMI was significantly higher than that detected by FAF (11.85 ± 3.92 mm2 and 5.67 ± 2.15 mm2, respectively, p < 0.05) and similar to that revealed by fundus photography (11.85 ± 3.92 mm2 and 10.58 ± 3.45 mm2, respectively, p = 0.277). (4) Conclusions: RMI appears to be a useful tool in the evaluation of ERMs. It allows for an accurate visualization of the real extension of the retinal folds and provides a precise structural assessment of the macula before surgery. Clinicians should be aware of RMI's advantages and should be able to use them to warrant a wide range of information and, thus, a more personalized therapeutic approach

Nucleocapsid protein of SARS-CoV-2 phase separates into RNA-rich polymerase-containing condensates

The etiologic agent of the Covid-19 pandemic is the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The viral membrane of SARS-CoV-2 surrounds a helical nucleocapsid in which the viral genome is encapsulated by the nucleocapsid protein. The nucleocapsid protein of SARS-CoV-2 is produced at high levels within infected cells, enhances the efficiency of viral RNA transcription, and is essential for viral replication. Here, we show that RNA induces cooperative liquid–liquid phase separation of the SARS-CoV-2 nucleocapsid protein. In agreement with its ability to phase separate in vitro, we show that the protein associates in cells with stress granules, cytoplasmic RNA/protein granules that form through liquid-liquid phase separation and are modulated by viruses to maximize replication efficiency. Liquid–liquid phase separation generates high-density protein/RNA condensates that recruit the RNA-dependent RNA polymerase complex of SARS-CoV-2 providing a mechanism for efficient transcription of viral RNA. Inhibition of RNA-induced phase separation of the nucleocapsid protein by small molecules or biologics thus can interfere with a key step in the SARS-CoV-2 replication cycle

Contributions of the N-terminal intrinsically disordered region of the severe acute respiratory syndrome coronavirus 2 nucleocapsid protein to RNA-induced phase separation

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein is an essential structural component of mature virions, encapsulating the genomic RNA and modulating RNA transcription and replication. Several of its activities might be associated with the protein's ability to undergo liquid–liquid phase separation. NSARS-CoV-2 contains an intrinsically disordered region at its N-terminus (NTE) that can be phosphorylated and is affected by mutations found in human COVID-19 infections, including in the Omicron variant of concern. Here, we show that NTE deletion decreases the range of RNA concentrations that can induce phase separation of NSARS-CoV-2. In addition, deletion of the prion-like NTE allows NSARS-CoV-2 droplets to retain their liquid-like nature during incubation. We further demonstrate that RNA-binding engages multiple parts of the NTE and changes NTE's structural properties. The results form the foundation to characterize the impact of N-terminal mutations and post-translational modifications on the molecular properties of the SARS-CoV-2 nucleocapsid protein

Liquid–liquid phase separation of tau: From molecular biophysics to physiology and disease

Biomolecular condensation via liquid–liquid phase separation (LLPS) of intrinsically disordered proteins/regions (IDPs/IDRs), with and without nucleic acids, has drawn widespread interest due to the rapidly unfolding role of phase-separated condensates in a diverse range of cellular functions and human diseases. Biomolecular condensates form via transient and multivalent intermolecular forces that sequester proteins and nucleic acids into liquid-like membrane-less compartments. However, aberrant phase transitions into gel-like or solid-like aggregates might play an important role in neurodegenerative and other diseases. Tau, a microtubule-associated neuronal IDP, is involved in microtubule stabilization, regulates axonal outgrowth and transport in neurons. A growing body of evidence indicates that tau can accomplish some of its cellular activities via LLPS. However, liquid-to-solid transition resulting in the abnormal aggregation of tau is associated with neurodegenerative diseases. The physical chemistry of tau is crucial for governing its propensity for biomolecular condensation which is governed by various intermolecular and intramolecular interactions leading to simple one-component and complex multi-component condensates. In this review, we aim at capturing the current scientific state in unveiling the intriguing molecular mechanism of phase separation of tau. We particularly focus on the amalgamation of existing and emerging biophysical tools that offer unique spatiotemporal resolutions on a wide range of length- and time-scales. We also discuss the link between quantitative biophysical measurements and novel biological insights into biomolecular condensation of tau. We believe that this account will provide a broad and multidisciplinary view of phase separation of tau and its association with physiology and disease

On the oxygen reduction reaction mechanism catalyzed by pd complexes on 2d carbon. A theoretical study

Oxygen Reduction Reaction (ORR) is the bottle-neck strategic reaction ruling the fuel cell efficiency process. The slow kinetics of the reaction require highly effective electrocatalysts for proper boosting. In this field, composite catalysts formed by carbon nanotubes functionalized with palladium(II) complexes showed surprising catalytic activity comparable to those of a commercial Pt electrode, but the catalytic mechanisms of these materials still remain open to discussion. In this paper, we propose the combination of experimental and theoretical results to unfold the elementary reaction steps underlying the ORR catalysis

Various applications of processing of olive leaves waste extracted with RSLDE: a green technology

There is no waste in nature. Everything that is produced has a purpose and everything that becomes waste can be transformed into a new resource, triggering a virtuous circuit that feeds itself. The circular economy of waste means a system in which the production-consumption-disposal process is overcome to replace it with a circular model, where the final waste product is re-introduced into the circulation as a secondary raw material. The logic to follow is that after consumption and before any disposal, it is necessary to activate virtuous processes such as reduce, reuse and recycling. This work focuses on the possible uses of a vegetable waste matrix, such as olive leaves. The olive tree (Olea europaea) is a fruit tree, cultivated for more than 3,500 years for its fruits and edible oil. However, just like oil, olive leaf contains a high amount of polyphenols, in particular oleuropein, one of the most powerful natural antioxidants known and hydroxytyrosol, which also has powerful antiseptic properties. Therefore, olive leaf extracts, thanks to the presence of oleuropein associated with hydroxytyrosol, represent a powerful natural antioxidant, a valid ally of the cardiovascular system. In addition, olive leaves are an excellent regulator of the digestive system: they regulate intestinal transit and above all eliminate fungi and other unwanted parasites from our body. Starting from these premises, in this work, a green extraction technique such as rapid solid liquid dynamic extraction (RSLDE) is compared with conventional maceration to obtain an olive leaf extract rich in antioxidants to be used in various sectors