Ultrafilter
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. Topologias de grupo enumeravelmente compactas: MA, forcing e ultrafiltros seletivos / Countably compact group topologies: MA, forcing and selective ultrafilters
É bem conhecido o fato de que todo grupo compacto tem sequências não triviais convergentes. A existência de grupos enumeravelmente compactos sem sequências não triviais convergentes, foi provada usando axiomas adicionais à axiomática usual ZFC: A. Hajnal e I. Juhász sob CH, E. K. van Douwen sob MA, A. H. Tomita sob MA(sigma-centrada) e R.E. Madariag
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 07/11/2011
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2. A GENERAL APPROACH TO QUANTIFIERS IN NATURAL DEDUCTION / UMA ABORDAGEM GERAL PARA QUANTIFICADORES EM DEDUÇÃO NATURAL
There are many kinds of deductive calculus. The axiomatic ones are the more usual. However, from the point of view of proof theory, Natural Deduction systems seem to be more interesting. This is the motivation for developping a technique that aims to ease the transformation from deductive calculus to Natural Deduction style. This work concentrates on the asp
Publicado em: 2004
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3. Concentration and Purification of Poliovirus by Ultrafiltration and Isopycnic Centrifugation1
A method is described by which poliovirus can be rapidly and simply concentrated by the use of a Diaflo XM-50 ultrafilter membrane. Freon-extracted ultrafilter concentrates banded in CsCl provided a 1,724-fold volumetric concentration of poliovirus. During concentration, trypsin-digested cellular material can pass through the ultrafilter membrane, thus provi
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4. An Efficient Electro-Ultrafilter1
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5. Apoplasmic and Protoplasmic Water Transport through the Parenchyma of the Potato Storage Organ.
Stationary volume fluxes through living and denatured parenchyma slices of the potato (Solanum tuberosum L.) storage organ were studied to estimate the hydraulic conductivity of the cell wall and to evaluate the significance of water transport through protoplasts, cell walls, and intercellular spaces. Slices were placed between liquid compartments, steady-st
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6. Ultrafiltration to reject human interleukin-1-inducing substances derived from bacterial cultures.
Interleukin-1 (IL-1), a polypeptide cytokine, is an important mediator of host responses to infection and injury. Picogram per milliliter concentrations of bacterial products (endo- or exotoxins) stimulate human monocytes to produce IL-1 in vitro. The design of this study was based on the clinical model of bacterial contamination of fluid intended to be dire
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7. Ultrafiltration as a Method for Concentrating Rift Valley Fever Virus Grown in Tissue Culture
Filtration by means of a Diaflo ultrafilter was used to concentrate three 1,000-ml lots and one 3,000-ml lot of tissue culture-grown Rift Valley fever virus. Quantitation of both infectivity and total protein was achieved. Water treatment with continued ultrafiltration of the virus concentrate provided a final virus product approximately 99.25% free of low-m
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8. Limit, logic, and computation
We introduce “ultrafilter limits” into the classical Turing model of computation and develop a paradigm for interpreting the problem of distinguishing the class P from NP as a logical problem of decidability. We use P(NP) to denote decision problems which can be solved on a (nondeterministic) Turing machine in polynomial time. The concept is that in an a
The National Academy of Sciences.
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9. Concentration and Detection of Cryptosporidium Oocysts in Surface Water Samples by Method 1622 Using Ultrafiltration and Capsule Filtration
The protozoan parasite Cryptosporidium parvum is known to occur widely in both source and drinking water and has caused waterborne outbreaks of gastroenteritis. To improve monitoring, the U.S. Environmental Protection Agency developed method 1622 for isolation and detection of Cryptosporidium oocysts in water. Method 1622 is performance based and involves fi
American Society for Microbiology.
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10. Abundance of Virus-Sized Non-DNase-Digestible DNA (Coated DNA) in Eutrophic Seawater
Total DNA concentration in 0.2-μm-pore-size Nuclepore filter filtrates (<0.2-μm fraction) of Tokyo Bay water was estimated to be 9 to 19 ng/ml by an immunochemical quantification method. Almost 90% of the DNA in the <0.2-μm fraction was found in the size fractions larger than 3.0 × 105 Da and 0.03 μm, and most was not susceptible to DNase digestion, tha
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11. Optimization of a Reusable Hollow-Fiber Ultrafilter for Simultaneous Concentration of Enteric Bacteria, Protozoa, and Viruses from Water
The detection and identification of pathogens from water samples remain challenging due to variations in recovery rates and the cost of procedures. Ultrafiltration offers the possibility to concentrate viral, bacterial, and protozoan organisms in a single process by using size-exclusion-based filtration. In this study, two hollow-fiber ultrafilters with 50,0
American Society for Microbiology.