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.

Biogeochemistry and bacteriology of ferrous iron oxidation in geothermal habitats

Conti, S. F. (Dartmouth Medical School, Hanover, N.H.), and T. D. Brock. Electron microscopy of cell fusion in conjugating Hansenula wingei. J. Bacteriol. 90:524–533. 1965.—The heterothallic yeast Hansenula wingei is a favorable organism for the study of the process of cell fusion, since strong agglutination of cells of the two mating types ensures a high percentage of cell fusions. The initial agglutination reaction results in cell-wall deformation, so that the walls in the region of contact are tightly appressed over an extensive area. The fusion process is initiated when the walls of two cells elongate, and this elongation seems to be restricted to the region where the cells touch. Occasionally, one cell is seen to push in the wall of the other, but in many cases both cells elongate equally, as would be expected in an isogamous organism. The precise disposition of the elongating wall probably reflects the manner in which the cells initially become associated in the agglutinated cell clump. Soon after wall elongation begins, cell-wall fusion occurs along the margin of contact. Only after fusion is complete is the wall separating the two cells dissolved away. If wall dissolution begins at one edge of the conjugation tube, a flap is formed in which can be seen the remnants of the fused walls. Alternatively, dissolution can begin at the center of the conjugation tube, proceeding towards the outside. Conjugating cells are uninucleate, and the nuclei are large and frequently lobed or elongated. After the conjugation tube is formed, the nuclei migrate towards the center, and fusion occurs only over a small region where the nuclear membranes come in contact. After nuclear fusion, the first diploid bud forms from the conjugation tube and at right angles to the tube axis. The diploid nucleus then migrates into this bud. Frequently, in the later stages of conjugation, a large vacuole develops in each of the original cells. All of the above events will occur in a medium devoid of a nitrogen source and in which vegetative budding will not occur.

Electron Microscopy of Cell Fusion in Conjugating Hansenula wingei

This account of studies on the algae and bacteria of North Island thermal areas records temperature, pH and species found in these microbial habitats, with special attention to organisms living at the highest temperatures. Thermal features were studied at Rotorua (Whakarewarewa and Ohinemutu), Waiotapu (Tourist Reserve and Lady Knox Geyser), Orakei Korako, Taupo Spa, Waikite Springs, Wairakei thermal valley, Wairakei geothermal field, Tikitere, Ketetahi, Lake Rotokawa (Taupo region), Waimangu, De Brett Thermal Hotel (Taupo). The upper temperature limit for blue‐green algae in New Zealand is 60–65°c, and the species living at the thermal limit is generally Mastigocladus laminosus, although in some cases Phormidium sp. or Synechococcus sp. was found. The Synechococcus sp. characteristic of high temperatures (73–74°c) present in North America was not found in New Zealand. In virtually all boiling pools (99–101°c) with pH values in the neutral and alkaline range bacteria were found, but in acidic boi...

https://www.tandfonline.com/doi/pdf/10.1080/00288330.1971.9515379

Microbiological studies of thermal habitats of the central volcanic region, North Island, New Zealand

Red blooms of snow algae consisting almost exclusively of large spherical red cells of Chlamydomonas nivalis (Bauer) Wille are widespread during the summer in the Beartooth Mountains in Montana and Wyoming. Field studies designed to examine the effects of temperature, light, and water potential on algal activity were performed with natural populations using photosynthetic /sup 14/C-HCO/sub 3//sup -/ or /sup 14/CO/sub 2/ incorporation as a measure of activity. The algae photosynthesized optimally at 5.4 x 10/sup 4/ lx, but were not inhibited by increased light intensity up to 8.6 x 10/sup 4/ lx, the maximum observed in the field. Photosynthesis was sensitive to a reduction in water potential, and since low water potentials develop in snow at temperatures below 0 C, it is unlikely that significant algal activity occurs at the sub-0 temperatures which occur throughout winter. Photosynthesis was much lower following melting of the snow, but this was probably due to decreased diffusion of CO/sub 2/. The optimal temperatures varied considerably among the different algal populations. Most samples photosynthesized optimally at 10 or 20/sup 0/C but retained substantial activity at temperatures as low as 0 or -3/sup 0/C. Exceptional samples photosynthesized optimally at 0 or -3/sup 0/C. It ismore » proposed that the varied temperature responses reflect the presence of different temperature strains. Taken together, the data suggest that development of the snow algae can occur only during the summer months.« less

Photosynthesis in the snow: the alga chlamydomonas nivalis (chlorophyceae)1

One of the strange features of life in the Yellowstone hot springs is that during summer the microbial mats in those springs rich in blue-green algae are usually orange or yellow in color, whereas the springs that are strikingly blue-green in color do not contain blue-green algae, but instead the eucaryotic alga Cyanidium caldarium. Hot springs containing Cyanidium are always acidic, with pH values less than 4, and at temperatures above 40°C this alga is the sole photosynthetic component, since no photosynthetic bacteria such as Chloroflexus live in such acidic habitats. Because of the striking appearance of Cyanidium mats, the alga has been observed for a long time, and has been variously called Chroococcus varius (Tilden, 1898), Protococcus botryoides f. caldarium (Tilden, 1898), Pleurocapsa caldaria (Collins et al., 1901), Palmellococcus thermalis (West, 1904), Pluto caldarius (Copeland, 1936), Dermocarpa caldaria (Drouet, 1943), and Rhodococcus caldarium (Hirose, 1958). The name Cyanidium caldarium was first used by Geitler and Ruttner (1936) the same year that Copeland described the organism as Pluto, but despite the euphony of the latter name, the name Cyanidium has taken precedent. A photomicrograph of typical cells of C. caldarium is shown in Figure 9.1.

Thomas D. Brock

Papers

Biogeochemistry and bacteriology of ferrous iron oxidation in geothermal habitats

Electron Microscopy of Cell Fusion in Conjugating Hansenula wingei

Microbiological studies of thermal habitats of the central volcanic region, North Island, New Zealand

Photosynthesis in the snow: the alga chlamydomonas nivalis (chlorophyceae)1

The Genus Cyanidium