28 research outputs found

    A new virus on maize in Nigeria: maize mild mottle virus

    No full text
    Maize (Zea mays) and itch grass (Rottboellia cochinchinensis) plants exhibiting a mild mosaic or mottle were collected from a farmer's field near Mokwa, Nigeria, in 1993. Icosahedral virions (approximately 28 to 30 nm) were purified from symptomatic tissue by differential centrifugation in 0.1 M phosphate buffer, pH 7.0. The virions are composed of one single-stranded positive-sense RNA of approximately 4,000 nucleotides and, as estimated by 12.5% sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), a capsid protein of approximately 28 kDa. The virus was readily detected in infected plants by enzyme-linked immunosorbent assay and immunoblot assays with a polyclonal rabbit antibody derived from purified virions. A partial cDNA library was generated with random primers. Sequence analyses of a cDNA clone representing a portion of the putative replicase gene aligned most closely with related sequences of viruses within the Tombusviridae. In particular, a region of 78 predicted amino acids surrounding the “GDD” replicase motif shares 73% identity with panicum mosaic virus and 61% identity with maize chlorotic mottle virus. The virus is readily transmitted by mechanical inoculation to sweet and dent corn, millet, and wheat. Currently it is not considered of economic importance in Nigeria. The data suggest that “maize mild mottle virus” is a newly identified virus infecting maize

    Rational suicide: uncertain moral ground

    No full text
    Background. The ambiguities involving end-of-life issues, such as physician-assisted suicide and voluntary stopping of eating and drinking, have caused a blurring of the definition of rational suicide and have prompted rich dialogue with moral deliberations that seem to be on disparate paths among bioethicists and other health care professionals. With the evolution of advanced medical technology extending life expectancy in older, disabled, and terminally ill people, rational suicide has become a critical issue of debate. Aim. The purpose of this article is to address the ethical positions supporting and opposing rational suicide and to consider whether coherence can be achieved through an ethic of care. Findings. Attitudes towards suicide have been controversial, varying from acceptance to non-acceptance depending on social, political and religious influences. Nursing attitudes are no different from general societal attitudes and, consequently, nurses are treading on uncertain moral ground. Conclusion. Nurses who have not reflected on the moral issues involved with rational suicide may be unprepared psychologically and professionally when working with patients who may be contemplating such actions
    corecore