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Influenza A viruses are highly infectious respiratory pathogens that can infect many species. Birds are the reservoir for all known influenza A subtypes; and novel influenza viruses can emerge from birds and infect mammalian species including humans. Because swine are susceptible to infection with both avian and human influenza viruses, novel reassortant influenza viruses can be generated in this mammalian species by reassortment of influenza viral segments leading to the 'mixing vessel' theory. There is no direct evidence that the reassortment events culminating in the 1918, 1957 or 1968 pandemic influenza viruses originated from pigs. Genetic reassortment among avian, human and/or swine influenza virus gene segments has occurred in pigs and some novel reassortant swine viruses have been transmitted to humans. Notably, novel reassortant H2N3 influenza viruses isolated from the US pigs, most likely infected with avian influenza viruses through surface water collected in ponds for cleaning barns and watering animals, had a similar genetic make-up to early isolates (1957) of the H2N2 human pandemic. These novel H2N3 swine viruses were able to cause disease in swine and mice and were infectious and highly transmissible in swine and ferrets without prior adaptation. The preceding example shows that pigs could transmit novel viruses from an avian reservoir to other mammalian species. Importantly, H2 viruses pose a substantial risk to humans because they have been absent from mammalian species since 1968 and people born after 1968 have little preexisting immunity to the H2 subtype. It is difficult to predict which virus will cause the next human pandemic and when that pandemic might begin. Importantly, the establishment and spread of a reassorted mammalian-adapted virus from pigs to humans could happen anywhere in the world. Therefore, both human and veterinary research needs to give more attention to potential cross-species transmission capacity of influenza A viruses. Keyswords: Swine, influenza A virus, mixing vessel, genetic reassortment, human pandemic, INTRODUCTION The ecology of influenza A viruses The presence of all subtypes influenza A viruses in wild aquatic birds poses serious health risks to a wide range of animal species. [...]

In September 2008, scientists from all across the globe gathered at Oxford to consider five related themes in combating avian influenza; epidemiology, vaccines, virulence and pathogenicity, immunology, and antivirals. Overarching [...]

Includes four articles that discuss the use of digital objects to represent value in a network environment; digital library initiatives at the central public funding organization for academic research in Germany; an application of the Digital Object Identifier System; and the Web site of the Fermi National Accelerator Laboratory. (LRW)

This article focuses on an unpublished paper on Pigouvian taxation, which was presented by economist William Vickrey at the economics session of the Air Pollution Control Association annual meeting in Cleveland on June 11, 1967. Mimeographed copies of it were distributed to the small audience of mostly engineers, and thereafter made no further effort to promulgate the piece. Nor does it appear that anyone outside original audience in Cleveland saw the pa- per, for no mention is made of it, or of any other paper by Vickrey. Had Vickrey's paper been circulated or properly published, some issues that proved to be very important in this area might have been investigated and argued five to ten years earlier than they actually were. Vickrey was the first to specifically address the "theoretical difficulty in the application of effluent charges posed by the problem of nonconvexity or concavity of the cost function." He cautioned that "Where concavities exist, there will in general be the possibility that there may be a number of "local maxima" at each of which the local equilibrium conditions may be satisfied."

Several information processing technologies which are capable of augmenting human performance in handling a range of emergency situations are featured in this discussion. Among the more sophisticated systems which have proven useful in enhancing information collection, transmission, and selective processing are packet radio networks, “expert planning systems,” multiple‐satellite technology, and such related emerging developments as “internetting” and “machine intelligence.” [ABSTRACT FROM PUBLISHER]

Because of the high complication rate encountered in performing intracardiac selective angiocardiography in infants using the concentrated and hence viscid radiopaque agents, 50 per cent sodium diatrizoate was employed in 65 consecutive infants under 20 lb for a total of 101 intracardiac injections, including 7 left ventricular injections. A comparison was made between this group and an earlier series consisting of 28 patients, for a total of 53 intracardiac injections of a more concentrated opaque. It was concluded that the administration of 2.5 to 9 ml of 50 per cent sodium diatrizoate, rarely exceeding 1 ml per kg, has resulted in excellent opacification of intracardiac structures. The low viscosity of this medium has yielded an increased flow rate at significantly decreased injection pressures, assuring delivery of the total bolus in 0.5 to 0.8 sec, i.e., within approximately one to two cardiac cycles. This contrast medium has proven successful in all infants under 15 lb, independent of age. It may be employed in babies between 15 to 20 lb, whose hearts are normal in size or only slightly enlarged; for infants weighing over 20 lb a more concentrated medium is preferred. No major complications were encountered. This technique has given good results even in the presence of large left-to right intracardiac shunts, and good opacification of the left heart chambers from pulmonary venous return flow has been obtained following right ventricular injections. [ABSTRACT FROM AUTHOR]

Influenza A viruses are highly infectious respiratory pathogens that can infect many species. Birds are the reservoir for all known influenza A subtypes; and novel influenza viruses can emerge from birds and infect mammalian species including humans. Because swine are susceptible to infection with both avian and human influenza viruses, novel reassortant influenza viruses can be generated in this mammalian species by reassortment of influenza viral segments leading to the "mixing vessel" theory. There is no direct evidence that the reassortment events culminating in the 1918, 1957 or 1968 pandemic influenza viruses originated from pigs. Genetic reassortment among avian, human and/or swine influenza virus gene segments has occurred in pigs and some novel reassortant swine viruses have been transmitted to humans. Notably, novel reassortant H2N3 influenza viruses isolated from the US pigs, most likely infected with avian influenza viruses through surface water collected in ponds for cleaning barns and watering animals, had a similar genetic make-up to early isolates (1957) of the H2N2 human pandemic. These novel H2N3 swine viruses were able to cause disease in swine and mice and were infectious and highly transmissible in swine and ferrets without prior adaptation. The preceding example shows that pigs could transmit novel viruses from an avian reservoir to other mammalian species. Importantly, H2 viruses pose a substantial risk to humans because they have been absent from mammalian species since 1968 and people born after 1968 have little preexisting immunity to the H2 subtype. It is difficult to predict which virus will cause the next human pandemic and when that pandemic might begin. Importantly, the establishment and spread of a reassorted mammalian-adapted virus from pigs to humans could happen anywhere in the world. Therefore, both human and veterinary research needs to give more attention to potential cross-species transmission capacity of influenza A viruses.