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<jats:p> Novel vaccines are urgently needed to reduce the burden of severe malaria. Using a differential whole-proteome screening method, we identified <jats:italic>Plasmodium falciparum</jats:italic> schizont egress antigen-1 (PfSEA-1), a 244-kilodalton parasite antigen expressed in schizont-infected red blood cells (RBCs). Antibodies to PfSEA-1 decreased parasite replication by arresting schizont rupture, and conditional disruption of PfSEA-1 resulted in a profound parasite replication defect. Vaccination of mice with recombinant <jats:italic>Plasmodium berghei</jats:italic> PbSEA-1 significantly reduced parasitemia and delayed mortality after lethal challenge with the <jats:italic>Plasmodium berghei</jats:italic> strain ANKA. Tanzanian children with antibodies to recombinant PfSEA-1A (rPfSEA-1A) did not experience severe malaria, and Kenyan adolescents and adults with antibodies to rPfSEA-1A had significantly lower parasite densities than individuals without these antibodies. By blocking schizont egress, PfSEA-1 may synergize with other vaccines targeting hepatocyte and RBC invasion. </jats:p>

<jats:p> The mineralogical constitution of the Earth’s mantle dictates the geophysical and geochemical properties of this region. Previous models of a perovskite-dominant lower mantle have been built on the assumption that the entire lower mantle down to the top of the D″ layer contains ferromagnesian silicate [(Mg,Fe)SiO <jats:sub>3</jats:sub> ] with nominally 10 mole percent Fe. On the basis of experiments in laser-heated diamond anvil cells, at pressures of 95 to 101 gigapascals and temperatures of 2200 to 2400 kelvin, we found that such perovskite is unstable; it loses its Fe and disproportionates to a nearly Fe-free MgSiO <jats:sub>3</jats:sub> perovskite phase and an Fe-rich phase with a hexagonal structure. This observation has implications for enigmatic seismic features beyond ~2000 kilometers depth and suggests that the lower mantle may contain previously unidentified major phases. </jats:p>

<jats:p>Black holes have been predicted to radiate particles and eventually evaporate, which has led to the information loss paradox and implies that the fundamental laws of quantum mechanics may be violated. Superstring theory, a consistent theory of quantum gravity, provides a possible solution to the paradox if evaporating black holes can actually be described in terms of standard quantum mechanical systems, as conjectured from the theory. Here, we test this conjecture by calculating the mass of a black hole in the corresponding quantum mechanical system numerically. Our results agree well with the prediction from gravity theory, including the leading quantum gravity correction. Our ability to simulate black holes offers the potential to further explore the yet mysterious nature of quantum gravity through well-established quantum mechanics.</jats:p>

<jats:p>The arrangement of atoms and bonds in a molecule influences its physical and chemical properties. The scanning tunneling microscope can provide electronic and vibrational signatures of single molecules. However, these signatures do not relate simply to the molecular structure and bonding. We constructed an inelastic tunneling probe based on the scanning tunneling microscope to sense the local potential energy landscape of an adsorbed molecule with a carbon monoxide (CO)–terminated tip. The skeletal structure and bonding of the molecule are revealed from imaging the spatial variations of a CO vibration as the CO-terminated tip probes the core of the interactions between adjacent atoms. An application of the inelastic tunneling probe reveals the sharing of hydrogen atoms among multiple centers in intramolecular and extramolecular bonding.</jats:p>