Climate Change, Aridity, and Internal Migration: Evidence from Census Microdata for 72 Countries

Whether and to what extent climatic factors influence migration has received widespread public and scientific attention. In this paper, we focus on the impacts of increased aridity and drought on internal migration using novel census-based data for 72 countries covering the period 1960-2016. Analyzing information on 107,916 interregional migration flows, we find that drought and aridity have a significant impact on human mobility, particularly in the hyper-arid and arid areas of Southern Europe, the Middle East and North Africa, and Southern Asia. Migration is shaped by the level of wealth, agricultural dependency, and urbanization in the area of origin. Different age and education groups respond differently to droughts and aridity highlighting the importance of differential mobility patterns across population groups in different geographic contexts

Plasmodium falciparum ligand binding to erythrocytes induce alterations in deformability essential for invasion

The most lethal form of malaria in humans is caused by Plasmodium falciparum. These parasites invade erythrocytes, a complex process involving multiple ligand-receptor interactions. The parasite makes initial contact with the erythrocyte followed by dramatic deformations linked to the function of the Erythrocyte binding antigen family and P. falciparum reticulocyte binding-like families. We show EBA-175 mediates substantial changes in the deformability of erythrocytes by binding to glycophorin A and activating a phosphorylation cascade that includes erythrocyte cytoskeletal proteins resulting in changes in the viscoelastic properties of the host cell. TRPM7 kinase inhibitors FTY720 and waixenicin A block the changes in the deformability of erythrocytes and inhibit merozoite invasion by directly inhibiting the phosphorylation cascade. Therefore, binding of P. falciparum parasites to the erythrocyte directly activate a signaling pathway through a phosphorylation cascade and this alters the viscoelastic properties of the host membrane conditioning it for successful invasion

Red blood cell invasion by Plasmodium vivax: Structural basis for DBP engagement of DARC

Plasmodium parasites use specialized ligands which bind to red blood cell (RBC) receptors during invasion. Defining the mechanism of receptor recognition is essential for the design of interventions against malaria. Here, we present the structural basis for Duffy antigen (DARC) engagement by P. vivax Duffy binding protein (DBP). We used NMR to map the core region of the DARC ectodomain contacted by the receptor binding domain of DBP (DBP-RII) and solved two distinct crystal structures of DBP-RII bound to this core region of DARC. Isothermal titration calorimetry studies show these structures are part of a multi-step binding pathway, and individual point mutations of residues contacting DARC result in a complete loss of RBC binding by DBP-RII. Two DBP-RII molecules sandwich either one or two DARC ectodomains, creating distinct heterotrimeric and heterotetrameric architectures. The DARC N-terminus forms an amphipathic helix upon DBP-RII binding. The studies reveal a receptor binding pocket in DBP and critical contacts in DARC, reveal novel targets for intervention, and suggest that targeting the critical DARC binding sites will lead to potent disruption of RBC engagement as complex assembly is dependent on DARC binding. These results allow for models to examine inter-species infection barriers, Plasmodium immune evasion mechanisms, P. knowlesi receptor-ligand specificity, and mechanisms of naturally acquired P. vivax immunity. The step-wise binding model identifies a possible mechanism by which signaling pathways could be activated during invasion. It is anticipated that the structural basis of DBP host-cell engagement will enable development of rational therapeutics targeting this interaction

Current trends on subtotal petrosectomy with cochlear implantation in recalcitrant chronic middle ear disorders

Objective. To establish the safety and effectiveness of subtotal petrosectomy with cochlear implantation in patients affected by chronic middle ear disorders to refractory to previous surgical treatments. Methods. A multicentre, retrospective study was conducted on patients affected by recalcitrant chronic middle ear disorders who underwent cochlear implantation in combi-nation with subtotal petrosectomy. Patients’ details were collected from databases of 11 Italian tertiary referral centres. Additionally, a review of the most updated literature was carried out. Results. 55 patients were included with a mean follow-up time of 44 months. Cholestea-toma was the most common middle ear recurrent pathology and 50.9% of patients had an open cavity. 80% of patients underwent a single stage surgery. One case of explantation for device failure was reported among the 7 patients with post-operative complications. Conclusions. Subtotal petrosectomy with cochlear implantation is a benchmark for management of patients with recalcitrant chronic middle ear disorders. A single stage procedure is the most recommended strategy. Optimal follow-up is still debated. Further studies are required to investigate the role of this surgery in paediatric patients

Aridification, precipitations and crop productivity: evidence from the aridity index

The economic effects of global warming have gained considerable attention in the recent economic literature. While the relationship between rainfall and agriculture is well known, precipitations alone do not capture the soil water availability, which depends on the evaporation of the water (potential evapotranspiration [PET]). This paper presents evidence of the relationship between aridification and agricultural productivity. We show that areas that have experienced increased precipitations have become arider due to increased PET. We then project future aridification patterns. We find that the global arid area will increase by 3.9 per cent by 2040. This implies a global loss of about 20 million tons of maize, 19 million tons of rice, 8 million tons of soybeans and 21 million tons of wheat until 2040 if no action to combat desertification is taken

Developments of an Interactive Sail Design Method

This paper presents a new tool for performing the integrated design and analysis of a sail. The features of the system are the geometrical definition of a sail shape, using the Bezier surface method, the creation of a finite element model for the non-linear structural analysis and a fluid-dynamic model for the aerodynamic analysis. The system has been developed using MATLAB(r). Recent sail design efforts have been focused on solving the aeroelastic behavior of the sail. The pressure distribution on a sail changes continuously, by virtue of cloth stretch and flexing. The sail shape determines the pressure distribution and, at the same time, the pressure distribution on the sail stretches and flexes the sail material determining its shape. This characteristic non-linear behavior requires iterative solution strategies to obtain the equilibrium configuration and evaluate the forces involved. The aeroelastic problem is tackled by combining structural with aerodynamic analysis. Firstly, pressure loads for a known sail-shape are computed (aerodynamic analysis). Secondly, the sail-shape is analyzed for the obtained external loads (structural analysis). The final solution is obtained by using an iterative analysis process, which involves both aerodynamic and the structural analysis. When the solution converges, it is possible to make design modifications

The long-term economic effects of aridification

We conduct a disaggregated empirical analysis of the economic effects of desertification, exploiting a novel grid-cell global dataset from 1990 to 2015. Our measure of desertification combines annual variation in precipitation and potential evapotranspiration of the soil. To ensure accuracy, we employed advanced spatial econometric techniques to account for the interdependence between economic development and both time and location. Our results indicate that a one standard deviation increase in desertification is associated with a 0.6% to 0.9% decrease in GDP per capita. Based on these estimates, we have predicted the potential impact of future desertification on economic development, with a particular focus on Africa and Southeast Asia

Climate, desertification, and local human development: evidence from 1564 regions around the world

How global warming affects human development is a central question for economists as well as social scientists. While most of the literature has focused on the impact of weather on income, less is known on the relationship between climate and local human development. This paper considers shocks in precipitation, temperature, and an original measure of soil aridity to first exploit the association between climate warming and human development, and second, on its dimensions. We show that while precipitations do not have a significant long-term impact on human development growth, variations in temperature and potential evapotranspiration negatively affect two of the three determinants of the Human Development Index, namely life expectancy at birth and education. These results suggest that other climate indicators, such as the potential evapo-transpiration of the soil, should be considered in addition to the standard indicators, when evaluating the localized economic effects of climate change

Lockdown measures and air quality: evidence from Italian provinces

The aim of this short communication is to estimate the effects of the implementation of more restrictive lockdown measures on pollution levels in Italy. Using a time series of weekly concentrations of PM10, PM2.5 and NO2 for the period 2016–2020 across 71 provinces, we find that the introduction of lockdown measures reduced the air concentration levels of PM10 and NO2 by 17–18%, while their effect on PM2.5 remains unclear. These results indicate that the lockdown had a significant positive impact in terms of lives saved and improved air quality

Developments of an Interactive Sail Design Method

This paper presents a new tool for performing the integrated design and analysis of a sail. The features of the system are the geometrical definition of a sail shape, using the Bezier surface method, the creation of a finite element model for the non-linear structural analysis and a fluid-dynamic model for the aerodynamic analysis. The system has been developed using MATLAB(r). Recent sail design efforts have been focused on solving the aeroelastic behavior of the sail. The pressure distribution on a sail changes continuously, by virtue of cloth stretch and flexing. The sail shape determines the pressure distribution and, at the same time, the pressure distribution on the sail stretches and flexes the sail material determining its shape. This characteristic non-linear behavior requires iterative solution strategies to obtain the equilibrium configuration and evaluate the forces involved. The aeroelastic problem is tackled by combining structural with aerodynamic analysis. Firstly, pressure loads for a known sail-shape are computed (aerodynamic analysis). Secondly, the sail-shape is analyzed for the obtained external loads (structural analysis). The final solution is obtained by using an iterative analysis process, which involves both aerodynamic and the structural analysis. When the solution converges, it is possible to make design modifications