The Escape Probability of Some Ions from Mars and Titan Ionospheres

The Kinetic Energy Release (KER) for various ionic species coming from two-body dissociations reactions, induced by double photoionization of CO 2, C2H2 and N2O neutral precursors of interest in planetary atmospheres, are reported. The KER distributions as a function of the VUV photon energy in the range of 30-65 eV are extracted from the coincidences spectra obtained by using tunable synchrotron radiation and electron-ion-ion coincidences coupled with ion imaging techniques. This experimental method, coupled with a computational analysis of the data based on a Monte Carlo trajectoriy simulation, allows to discuss about the probability for some ionic species to escape the upper atmosphere of Mars and Titan. In fact, the KER measured for H+, C+, CH+, CH , N+, O+ and CO+ fragment ions are ranging between 1.0 and 6.0 eV, and these translational energy contents are large enough to allow these ionic species in participating in the atmospheric escape from Mars and Titan into space. © 2014 Springer International Publishing

Genome-wide association study identifies human genetic variants associated with fatal outcome from Lassa fever.

Infection with Lassa virus (LASV) can cause Lassa fever, a haemorrhagic illness with an estimated fatality rate of 29.7%, but causes no or mild symptoms in many individuals. Here, to investigate whether human genetic variation underlies the heterogeneity of LASV infection, we carried out genome-wide association studies (GWAS) as well as seroprevalence surveys, human leukocyte antigen typing and high-throughput variant functional characterization assays. We analysed Lassa fever susceptibility and fatal outcomes in 533 cases of Lassa fever and 1,986 population controls recruited over a 7 year period in Nigeria and Sierra Leone. We detected genome-wide significant variant associations with Lassa fever fatal outcomes near GRM7 and LIF in the Nigerian cohort. We also show that a haplotype bearing signatures of positive selection and overlapping LARGE1, a required LASV entry factor, is associated with decreased risk of Lassa fever in the Nigerian cohort but not in the Sierra Leone cohort. Overall, we identified variants and genes that may impact the risk of severe Lassa fever, demonstrating how GWAS can provide insight into viral pathogenesis

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

The past 2 years, during which waves of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants swept the globe, have starkly highlighted health disparities across nations. Tegally et al. show how the coordinated efforts of talented African scientists have in a short time made great contributions to pandemic surveillance and data gathering. Their efforts and initiatives have provided early warning that has likely benefited wealthier countries more than their own. Genomic surveillance identified the emergence of the highly transmissible Beta and Omicron variants and now the appearance of Omicron sublineages in Africa. However, it is imperative that technology transfer for diagnostics and vaccines, as well the logistic wherewithal to produce and deploy them, match the data-gathering effort