3,543 research outputs found
Letter from Edwin E. Ferguson, Regional Attorney, War Relocation Authority, to Ernest Besig, Director, American Civil Liberties Union of Northern California, November 25, 1942
No full textLetter from Edwin E. Ferguson to Ernest Besig, in which Ferguson writes that the San Francisco War Relocation Authority office will be moving to Washington. Ferguson expresses fondness for Besig.The ACLU-Northern California case file records contain legal documents and correspondence pertaining to the case argued before the Supreme Court in Korematsu v. United States (1944), challenging the constitutionality of Executive Order 9066
Ferguson School District No. 4573
No full textPhotograph - A view of Ferguson School building near Athabasca, Alberta. ATS 24-66-21-W
Characteristics of distributed parameter isolators
No full textThe widely used traditional massless isolator model is only valid at relatively low frequencies. In this paper two classes of distributed parameter isolator, non-dispersive and dispersive, which are valid over a wide range of frequencies, are studied and compared. The important characteristics of such distributed parameter isolators in isolating a mass are given, as are the parameters which control the isolator performance at various frequencies. The theoretical findings for one distributed parameter isolator are validated experimentally using a helical spring, as an example of a non-dispersive isolator
Velocity feedback control for vibration isolation systems containing a distributed parameter system
No full textActive vibration isolation of a system with a distributed parameter isolator using absolute velocity feedback control
No full textThis paper is concerned with the active isolation of a system containing a distributed parameter isolator using absolute velocity feedback control. The main differences between this type of system and one with a massless isolator, is that there are isolator resonances. It is shown that the vibration at these resonance frequencies cannot be suppressed using a simple velocity feedback control strategy. Moreover, it is found that the isolator resonances can cause the control system to become unstable, if the isolated equipment is supported on a flexible base. A stability criterion based on the mode shapes of the system is presented. Two techniques to stabilise the system are investigated and compared. The first involves the addition of mass on the base structure, and the second involves an electronic lead compensator. Experimental results are presented to support the theoretical findings. It is shown that even if the instability due to the isolator resonances and flexibility of the base can be prevented, the instability due to the flexibility of the equipment remains a proble
Biochemistry and molecular biology of nitrification.
No full textThe biochemistry and molecular biology of nitrification are poorly understood, almost certainly related to the difficult problem of growing large enough quantities of cells from which to prepare vesicular membranes and purified proteins. This chapter explains the biochemistry and molecular biology of nitrification. Nitrosomonas and Nitrobacter depend on a chemiosmotic mechanism of energy transduction. Many of the special biochemical features of Nitrosomonas and Nitrobacter need to be understood in the context of the ability of the electron transport system to catalyze reversed electron transfer. The demonstration of H_ pumping by intact cells fed with electrons from the nonphysiological donor ascorbate can be taken as support for the H_ pumping activity. The genome sequence clearly shows two reading frames, designated NorA and NorB on the basis of earlier partial sequence information. Bioenergetic arguments have suggested a location at the cytoplasmic surface, but immunolabeling studies have indicated the opposite. The oxidation of ammonia to NO2- by Nitrosomonas is not a straightforward process. The idea that ubiquinol provides electrons for the ammonia mono-oxygenase is supported by the fact that partially purified preparations of the enzyme can use duroquinol as electron donor
Introduction to the biochemistry and molecular biology of denitrification.
No full textThis chapter provides an overview of the biochemistry and genetics of denitrification in such organisms. It considers the aspects of denitrification that occur in archaea and certain fungi. Denitrification has been mostly studied in Paracoccus denitrificans and Pseudomonas stutzeri and so it describes denitrification for each of these organisms in turn before considering to what extent general principles can be discerned. In recent years, high-resolution crystal structures have become available for these enzymes with the exception of the structure for NO-reductase. In general, the proteins required for denitrification are only produced under (close to) anaerobic conditions, and if anaerobically grown, cells are exposed to O2 and then the activities of the proteins are inhibited. Specialized denitrifiers, such as P. denitrificans and the denitrifying Pseudomonads, contain more than 40 genes, which encode the proteins that make up a full denitrification pathway. They include the structural genes for the enzymes and e- donors, their regulators as well as many accessory genes required for assembly, cofactor synthesis, and insertion into the enzymes. In contrast, some denitrifiers can only carry out the two central reactions of the pathway and use these activities to support growth, but the cost of maintaining this capability is a very small amount of genome space. It provides insights into the regulation of gene expression and the way in which some denitrification enzymes play different roles in bacteria
The prokaryotic nitrate reductases.
No full textThis chapter reviews the structural organization and bioenergetics of the four prokaryotic NO3 reductases and the eukaryotic enzyme and explores the possible mechanisms of NO3 transport. The membrane-bound NO3- reductase with the active site facing the cytoplasm is usually a three-subunit enzyme composed of NarGHI. The Mo ion of NarG is coordinated by an aspartate ligand provided by the polypeptide chain. Adjacent to the structural genes of NarGHI in many denitrifying bacteria are one or two members of genes encoding transport proteins generally known as NarK family proteins. Where respiratory NO3 reduction has been identified in Archaea, it is predicted to take place in a catalytic subunit with a twin arginine-dependent translocase (TAT) signal peptide, which may serve to export folded redox proteins across the cytoplasmic membrane. Periplasmic NO3 reductases (Nap) are also linked to quinol oxidation in respiratory electron transport chains but do not transduce the free energy in the QH2NO3 coupled into an H motive force. Bioinformatic analyses reveal that the Nap is phylogenetically widespread in proteobacteria, but detailed biochemical and spectroscopic studies have been restricted to enzymes from relatively few species. Some fungi have the capacity to reduce NO3 as part of a denitrification process and here the NO3 reductase is located in the mitochondrial membrane and is likely to emerge as being a prokaryotic pNar or nNar type
Letter from Robert Jemison, Jr., Tuskaloosa, Alabama to Mr. S. J. Ferguson, Alabama, August 2, 1862
No full text- …
