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.

Buoyancy regulation by planktonic blue-green algae in Lake Mendota, Wisconsin

The isolation of a halophilic blue-green alga, Aphanothece halophytica, from Great Salt Lake is described. The organism was cultured from waters with salinities up to saturated NaC1 (about 30% w/v). It has an optimum salinity for growth of about 16% NaC1, but can grow very slowly even in saturated NaC1. Based on the study of the Great Salt Lake organism, and on a review of the earlier literature, it is concluded that despite recent reports to the contrary, true halophilic blue-green algae do exist.

Halophilic-blue-green algae

The discovery of the genus Thermus (Brock and Freeze, 1969) provided our first impetus for detailed studies on the physiology of thermophilic bacteria. Its discovery was one of the simpler things we did, because enrichment and culture were so easy. We used a synthetic salts medium which had been shown to be suitable for growth of hot spring algae, added relatively low concentrations of organic compounds, and incubated at 70° C. The latter is of most importance. Before we began our work, the standard temperature for isolating and growing thermophilic bacteria had been 55°C, a temperature that the food microbiologists had used since the time of Cameron and Esty (Farrell and Campbell, 1969). At this temperature, and with the usual media, all one generally gets in culture is Bacillus stearothermophilus, a widespread, soil-borne sporeformer. Although this organism is of considerable importance in spoilage of canned foods, it is hardly of much importance in natural thermal environments, despite the fact that it can be routinely isolated (Fields, 1970). Microscopically, one never sees organisms resembling B. stearothermophilus. This organism is gram-positive; if one does gram stains of natural material, one never sees anything gram-positive, although gram-negative bacteria abound.

The Genus Thermus

IN analysing the influence of specific environmental factors on growth, it is desirable to study habitats where only a single factor varies. Hot springs provide suitable habitats where temperature is the only variable, so that the relation of temperature to biological development can be measured directly.

Temperature Optima for Algal Development in Yellowstone and Iceland Hot Springs

Thermal algae in alkaline hot springs of Yellowstone National Park (Wyoming) grow as compact mats in which self-shading is extensive, as shown by measurement by autoradiography of photosynthetic activity of cells at different levels in the mat. The effect of light intensity on photosynthesis of the algal mats was studied using neutral density filters during incubation with 14CO2. Despite the intense sunlight at the altitude of Yellowstone, light inhibition by full sunlight was observed only occasionally; the rate of photosynthesis fell progressively with decreasing light, although the most efficient use was at 7–14% of full sunlight. Later, the light intensity over portions of the algal mats was reduced to 18% of full sunlight by installing neutral density glass plates, and changes of chlorophyll content, cell number, and response of photosynthesis to light intensity were determined over the next year. Although the chlorophyll content of the algae at the surface of the mat rose quickly, the chlorophyll content of the mat as a whole rose slowly or not at all; the photosynthetic response of the algal mats to full and reduced sunlight also changed slowly or not at all. Although individual algal cells can adapt rapidly to changes in light, the entire population, because of its existence in compact mats, adapts slowly. At the latitude of Yellowstone there is sufficient light throughout the year to enable algal growth to occur even at temperatures near the upper limit at which blue-green algae can grow; in Iceland, hot spring algae cannot grow during several winter months. Natural ultraviolet radiation neither inhibited nor stimulated photosynthesis.

https://aslopubs.onlinelibrary.wiley.com/doi/pdf/10.4319/lo.1969.14.3.0334

Thomas D. Brock

Papers

Buoyancy regulation by planktonic blue-green algae in Lake Mendota, Wisconsin

Halophilic-blue-green algae

The Genus Thermus

Temperature Optima for Algal Development in Yellowstone and Iceland Hot Springs

Effect of light intensity on photosynthesis by thermal algae adapted to natural and reduced sunlight1