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Some active asteroids have been proposed to be the result of impact events. Because active asteroids are generally discovered serendipitously only after their tail formation, the process of the impact ejecta evolving into a tail has never been directly observed. NASA's Double Asteroid Redirection Test (DART) mission, apart from having successfully changed the orbital period of Dimorphos, demonstrated the activation process of an asteroid from an impact under precisely known impact conditions. Here we report the observations of the DART impact ejecta with the Hubble Space Telescope (HST) from impact time T+15 minutes to T+18.5 days at spatial resolutions of ~2.1 km per pixel. Our observations reveal a complex evolution of ejecta, which is first dominated by the gravitational interaction between the Didymos binary system and the ejected dust and later by solar radiation pressure. The lowest-speed ejecta dispersed via a sustained tail that displayed a consistent morphology with previously observed asteroid tails thought to be produced by impact. The ejecta evolution following DART's controlled impact experiment thus provides a framework for understanding the fundamental mechanisms acting on asteroids disrupted by natural impact., accepted by Nature

THE success of adenoviral vectors for gene therapy of lung disease in cystic fibrosis (CF) depends on efficient transfer of the complementary DNA encoding the correct version of the cystic fibrosis transmembrane regulator (CFTR) to the affected columnar epithelial cells lining the airways of the lung. Pre-clinical studies in vitro suggest that low doses of adenovirus vectors carrying this CFTR cDNA can correct defective Cl− transport in cultured human CF airway epithelia1. Here we use mice carrying the disrupted CF gene2 to test the efficacy of this transfer system in vivo. We find that even repeated high doses can only partially (50%) correct the CF defect in Cl− transport in vivo and do not correct the Na+ transport defect at all. We investigated this discrepancy between the in vivo and in vitro transfer efficiency using CF mouse and human samples, and found that it reflects a difference in the susceptibility to adenovirus-5 transduction of the epithelial cell types dosed in vivo (columnar) and in vitro (basal-cell-like). These studies indicate that more efficient adenoviral gene-transfer vectors and/or refinement of dosing strategies are needed for therapy of CF lung disease.

HYPERGAMMAGLOBULINAEMIA is a prominent feature of human malaria. Serum levels of IgM and IgG rise rapidly in acute infections1, and malaria has been implicated as an important cause of the raised levels of these immunoglobulins and the increased prevalence of rheumatoid factor and other autoantibodies found in healthy subjects in many parts of the tropics. Only a small proportion of the immunoglobulin produced in malaria can be shown to be specific antibody2. The mechanisms underlying the production of large amounts of nonspecific immunoglobulin in malaria have not been established. Excessive immunoglobulin production could result from a breakdown in normal control mechanisms, perhaps as a consequence of the deletion of suppressor T cells. Alternatively, it could be due to the production during malarial infection of a substance capable of stimulating lymphocytes nonspecifically3. Here we present evidence for the production of a mitogen in children with acute Plasmodium falciparum malaria.

RABIES virus has occasionally been isolated from feral rats1 and yet rodents are not considered to be a significant reservoir of sylvatic rabies2. These conclusions are based on negative results of surveys of small mammal species in areas in which rabies is endemic2,3. The isolation of rabies virus from a field rat, Bandicoota indicus, in the course of routine diagnostic procedures prompted a survey of several small mammals in Thailand, a country where rabies is endemic. When it was certain that the virus was present in a number of Bandicoota indicus, it then became important to determine whether overt disease occurred and if virus was being transmitted as an inapparent infection in the species. The results of the survey and preliminary data on the epidemiology of rabies in Bandicoota indicus are the subject of this report.

THE transmission of rabies by bats was first reported in 1921 (ref. 1). Vampire bats (Desmodus rotundus murinus) have been found to be an important carrier of sylvatic rabies in South America2, and they have been known to shed the virus in their saliva for long periods of time without apparent illness3. Since 1953, when the first rabies isolate from bats in the United States was made from a yellow bat (Dasypterus floridanus) in Florida, there have been more than five hundred isolates from bats in at least thirty-six States4. A survey of the literature has failed to reveal reports of rabies in bats in south-east Asia, and publications of the World Health Organization5,6 state that surveys of bat rabies in Asia have been consistently negative. The same statement about bat rabies in Europe, however, was refuted by Pitzschke7, who isolated rabies virus from a wide-winged bat (Epitescus serotinus) in Thuringia, Germany. The high prevalence of rabies in Thailand and the dense bat population prompted us to investigate the disease in bats in this area.

THE effects of a lethal injection of cobra venom, rattlesnake venom, or E. coli endotoxin on the cardiovascular system of the dog and monkey have been described previously in detail. The administration of endotoxin results in hypotension, acidosis, haemolysis, and renal failure1–4. A similar effect is seen following the administration of snake venom5,6. No reports, however, describe the effects of these compounds on the central nervous system. The purpose of work recorded here, therefore, was to determine if a change in cortical electrical activity follows a lethal injection of these toxins.