1. A description is given of the construction details and operation characteristics of an improved type of air-driven ultracentrifuge operating in vacuum and suitable for the determination of sedimentation constants of protein molecules. 2. The rotor of the centrifuge is made of a forged aluminum alloy; it is oval in shape, measures 185 mm. at its greatest diameter, and weighs 3,430 gm. It carr...

The alkaline-lysis mini-preparation method of isolating plasmid DNA includes several time-consuming steps. Here we provide a shortened protocol in which the volumes and incubation times have been altered (in particular the ethanol precipitation step) and the phenol extraction and RNAse digestion omitted completely. Recently a mini-prep method has been published requiring the use of caesium chlo...

This article presents an analytical model, originally developed in the 1980s, for the gas centrifuge and uses this methodology to determine the main design and operational characteristics of several hypothetical centrifuge designs. A series of simulations for a typical first-generation machine is used to assess the relevance of important breakout scenarios, including batch recycling and cascade...

The basic principles of rate centrifugation in the large volume zonal centrifuge and its application to the separation of abnormal or rarely occurring cells in the blood are described. Details of the method, gradient media, and collection and examination of the fractions obtained are given. A description of the cells found in normal human blood, in a subject undergoing known immunological stimu...

Purpose We test the ability of next-generation sequencing, combined with computational analysis, to identify a range of organisms causing infectious keratitis. Methods This retrospective study evaluated 16 cases of infectious keratitis and four control corneas in formalin-fixed tissues from the pathology laboratory. Infectious cases also were analyzed in the microbiology laboratory using cult...

The mechanical behavior of saturated soil is mainly governed by the interaction between the soil skeleton and the pore fluid, and this interaction may lead to significant loss of strength known as liquefaction under seismic loading conditions. The main objective of this paper is to implement a cyclic constitutive model based on fuzzy set plasticity theory, which is capable of modeling soil dila...