Phylogenetic identification and in situ detection of individual microbial cells without cultivation.

1. Discussion Alkalinity of a water is its acid-neutralizing capacity. It is the sum of all the titratable bases. The measured value may vary significantly with the end-point pH used. Alkalinity is a measure of an aggregate property of water and can be interpreted in terms of specific substances only when the chemical composition of the sample is known. Alkalinity is significant in many uses and treatments of natural waters and wastewaters. Because the alkalinity of many surface waters is primarily a function of carbonate, bicarbonate, and hydroxide content, it is taken as an indication of the concentration of these constitutents. The measured values also may include contributions from borates, phosphates, silicates, or other bases if these are present. Alkalinity in excess of alkaline earth metal concentrations is significant in determining the suitability of a water for irrigation. Alkalinity measurements are used in the interpretation and control of water and wastewater treatment processes. Raw domestic wastewater has an alkalinity less than, or only slightly greater than, that of the water supply. Properly operating anaerobic digesters typically have supernatant alkalinities in the range of 2000 to 4000 mg calcium carbonate (CaCO3)/L. 1

Standard methods for the examination of water and waste water.

What do a seventeenth-century mortality table (whose causes of death include "fainted in a bath," "frighted," and "itch"); the identification of South Africans during apartheid as European, Asian, colored, or black; and the separation of machine- from hand-washables have in common? All are examples of classification -- the scaffolding of information infrastructures. In Sorting Things Out, Geoffrey C. Bowker and Susan Leigh Star explore the role of categories and standards in shaping the modern world. In a clear and lively style, they investigate a variety of classification systems, including the International Classification of Diseases, the Nursing Interventions Classification, race classification under apartheid in South Africa, and the classification of viruses and of tuberculosis. The authors emphasize the role of invisibility in the process by which classification orders human interaction. They examine how categories are made and kept invisible, and how people can change this invisibility when necessary. They also explore systems of classification as part of the built information environment. Much as an urban historian would review highway permits and zoning decisions to tell a city's story, the authors review archives of classification design to understand how decisions have been made. Sorting Things Out has a moral agenda, for each standard and category valorizes some point of view and silences another. Standards and classifications produce advantage or suffering. Jobs are made and lost; some regions benefit at the expense of others. How these choices are made and how we think about that process are at the moral and political core of this work. The book is an important empirical source for understanding the building of information infrastructures.

https://www.reciis.icict.fiocruz.br/index.php/reciis/article/download/794/1436

Sorting Things Out: Classification and Its Consequences

Overview of membrane science and technology membrane transport theory membrane and modules concentration polarization reverse osmosis ultrafiltration microfiltration gas separation pervaporation ion exchange membrane processes - electrodialysis carrier facilitated transport medical applications of membranes other membranes processed.

Membrane Technology and Applications

Bacteriocins of gram-positive bacteria.

A molecular model for chemical and biological differences between streptomycin and dihydrostreptomycin.

Novobiocin affects a wide variety of biochemical and biological processes in bacteria, whereas most other antibiotics seem to affect one specific process. All of the processes known to be affected by novobiocin require magnesium ions, and in a number of cases magnesium deficiency mimics the action of the antibiotic. Evidence is presented that novobiocin complexes with magnesium ions.

http://science.sciencemag.org/content/sci/136/3513/316.full.pdf

Magnesium binding as an explanation of the mode of action of novobiocin.

Methods are described for measuring the concentration and vertical distribution of sulfide, elemental sulfur, and sulfate in benthic mats consisting of blue-green algae and photosynthetic bacteria. For visualizing microzonation of sulfide production, cores of the mat are placed in ferrous ammonium sulfate agar and incubated for 24 h. Zones of sulfide production are then revealed as black bands of ferrous sulfide of varying thickness. For quantitative measurement, cores are cut into segments, extracted, and assayed by colorimetric methods. Sulfide formation never occurs in the top 3 mm of the mat and occurs mainly in a thick rather diffuse zone between about 3-10 mm, below which extremely thin laminae of sulfide production are seen. The techniques reported should have wider utility and are especially useful in revealing location of reducing conditions within stratified mats.

https://aslopubs.onlinelibrary.wiley.com/doi/pdf/10.4319/lo.1976.21.2.0237

Vertical distribution of sulfur species in benthic algal mats1

Brock, Thomas D. (Indiana University, Bloomington). Biochemical and cellular changes occurring during conjugation in Hansenula wingei. J. Bacteriol. 90:1019–1025. 1954.—A technique has been devised for deagglutinating mixed populations of conjugating cells so as to be able to visualize microscopically early stages of the conjugation process. A cell can form a conjugation tube only when in contact with a cell of opposite mating type, but may do so even if the mate is unresponsive or ultraviolet-inactivated. Cell fusion occurs, however, only when both cells are able to form conjugation tubes in a region of contact. Fusion begins almost as soon as the two cells begin to form protuberances, and long before any dissolution of cell-wall material between the cells occurs. A cell which has conjugated in one region of its cell wall is still able to conjugate with another cell in another region, so that triply and quadruply conjugated cells are occasionally formed. There is no significant net increase in deoxyribonucleic acid, ribonucleic acid, protein, or carbohydrate which might be related to the conjugation process, because any minor changes that occur in these components are also detected when cells of only one mating type are incubated or when the conjugation process is inhibited with the antibiotic cycloheximide. Changes in activity of β-1,3-glucanase (with laminarin as substrate) and β-1,6-glucanase (with pustulan as substrate) have been measured during the conjugation process, in addition to changes in the activity of several control enzymes which would not be expected to be related to the conjugation process. Significant increases in invertase (sucrase), laminarinase, and pustulanase were detected, and minimal increases occurred in β-glucosidase and acid phosphatase. However, these same increases were also observed in controls involving only one mating type; thus, these increases are probably not related to the conjugation process, but may be a result of other processes which probably occur during incubation in the conjugation medium.

/pdf/biochemical-and-cellular-changes-occurring-during-3t19y4t6c8.pdf

Biochemical and Cellular Changes Occurring During Conjugation in Hansenula wingei

Frequencies of thermal springs of various pH values are given for the main thermal areas in Yellowstone Park, other parts of the western United States, New Zealand, and Iceland. A bimodal distribution curve was obtained for many springs with pH values of 2-4 and 7-9 but relatively few in between. These data provide quantitative evidence for the existence of two main kinds of thermal springs: acid sulfate and neutral bicarbonate.

Thomas D. Brock

Papers

A molecular model for chemical and biological differences between streptomycin and dihydrostreptomycin.

Magnesium binding as an explanation of the mode of action of novobiocin.

Vertical distribution of sulfur species in benthic algal mats1

Biochemical and Cellular Changes Occurring During Conjugation in Hansenula wingei

Bimodal Distribution of pH Values of Thermal Springs of the World