46 research outputs found

    Size Doesn't Matter: Towards a More Inclusive Philosophy of Biology

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    notes: As the primary author, O’Malley drafted the paper, and gathered and analysed data (scientific papers and talks). Conceptual analysis was conducted by both authors.publication-status: Publishedtypes: ArticlePhilosophers of biology, along with everyone else, generally perceive life to fall into two broad categories, the microbes and macrobes, and then pay most of their attention to the latter. ‘Macrobe’ is the word we propose for larger life forms, and we use it as part of an argument for microbial equality. We suggest that taking more notice of microbes – the dominant life form on the planet, both now and throughout evolutionary history – will transform some of the philosophy of biology’s standard ideas on ontology, evolution, taxonomy and biodiversity. We set out a number of recent developments in microbiology – including biofilm formation, chemotaxis, quorum sensing and gene transfer – that highlight microbial capacities for cooperation and communication and break down conventional thinking that microbes are solely or primarily single-celled organisms. These insights also bring new perspectives to the levels of selection debate, as well as to discussions of the evolution and nature of multicellularity, and to neo-Darwinian understandings of evolutionary mechanisms. We show how these revisions lead to further complications for microbial classification and the philosophies of systematics and biodiversity. Incorporating microbial insights into the philosophy of biology will challenge many of its assumptions, but also give greater scope and depth to its investigations

    The effects of amphotericin b, fluconazole and miconazole on neutrophil and lymphocyte function in a Guinea pig model

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    We studied the effects of amphotericin B, fluconazole and miconazole on Guinea pig neutrophil and lymphocyte function. Neutrophil adherence, chemotaxis, and deoxyglucose uptake and mitogen-induced lymphocyte proliferation were examined. The drugs were administered intraperitoneally in varying dosages based on those used therapeutically, either as a single infusion or daily for 3 days. Miconazole at high dosage (60 mg/kg) suppressed mitogen-induced lymphocyte proliferation, otherwise a single dose of any of the drugs had no effect on neutrophil or lymphocyte function irrespective of concentration used. Variable stimulative or suppressive effects on neutrophil and lymphocyte function were observed after three daily doses of each drug, but there was no dose-response pattern and the effects were erratic. The data show that, contrary to previous findings in vitro, amphotericin B, fluconazole and miconazole were not consistently immunosuppressive in vivo in this animal model

    Test of 6-inch-thick pressure vessels. Series 1: intermediate test vessels V-1 and V-2

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    The intermediate vessel tests have been subdivided into four seriesi flaws in cylindrical vessels, A508, class 2 forging steel-two vessels; flaws in cylindrical vessels with longitudinal weld seams, A508, class 2 forging steel, submerged-arc welds-three vessels; flaws in cylindrical vessels wlth longitudinal weld seams, A533, grade B, class l plate steel, submerged-arc weld-two vessels; and cylindrical vessels with radially attached nozzles, vessels of A508, chass 2 forging steel and A533, grade B, class 1 plate steel; nozzle of A508 class 2 forging steel-three vessels. A comprehensive description of the pertinent factors considered in the design of the vessels is presented. Construction of the test facility and documentation of test results and fracture predictions are included. Emphasis is placed on providing the test results in such a manner that they form a resource for amy investigators interested in the problem of fracture. (auth

    Test of 6-in. -thick pressure vessels. Series 3: intermediate test vessel V-7A under sustained loading. [BWR; PWR]

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    HSST intermediate test vessel V-7 was repaired after being tested hydrostatically to leakage and was retested pneumatically as vessel V-7A. Except for the method of applying the load, the conditions in both tests were nearly identical. In each case, a sharp outside surface flaw 547 mm long (18 in.) by about 135 mm deep (5.3 in.) was prepared in the 152-mm-thick (6-in.) test cylinder of A533, grade B, class 1 steel. The inside surface of vessel V-7A was sealed in the region of the flaw by a thin metal patch so that pressure could be sustained after rupture. Vessel V-7A failed by rupture of the flaw ligament without burst, as expected. Rupture occurred at 144.3 MPa (20.92 ksi), after which pressure was sustained for 30 min without any indication of instability. The rupture pressure of vessel V-7A was about 2 percent less than that of vessel V-7

    Optimization of experimental designs by incorporating NIF facility impacts

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    For experimental campaigns on the National Ignition Facility (NIF) to be successful, they must obtain useful data without causing unacceptable impact on the facility. Of particular concern is excessive damage to optics and diagnostic components. There are 192 fused silica main debris shields (MDS) exposed to the potentially hostile target chamber environment on each shot. Damage in these optics results either from the interaction of laser light with contamination and pre-existing imperfections on the optic surface or from the impact of shrapnel fragments. Mitigation of this second damage source is possible by identifying shrapnel sources and shielding optics from them. It was recently demonstrated that the addition of 1.1-mm thick borosilicate disposable debris shields (DDS) blocks the majority of debris and shrapnel fragments from reaching the relatively expensive MDS's. However, DDS's cannot stop large, fast moving fragments. We have experimentally demonstrated one shrapnel mitigation technique showing that it is possible to direct fast moving fragments by changing the source orientation, in this case a Ta pinhole array. Another mitigation method is to change the source material to one that produces smaller fragments. Simulations and validating experiments are necessary to determine which fragments can penetrate or break 1-3 mm thick DDS's. Three-dimensional modeling of complex target-diagnostic configurations is necessary to predict the size, velocity, and spatial distribution of shrapnel fragments. The tools we are developing will be used to assure that all NIF experimental campaigns meet the requirements on allowed level of debris and shrapnel generation
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