Physical and chemical data of nitrogen fixation.

Mode of access: Internet.

The Needle, Étretat

Claude Monet; 2 ft. 1 35/64 in. x 81 ft. 1 13/64 in.; oil on canvas

Manual of the system of teaching reading, writing, arithmetic, and needle-work, in the elementary schools of the British and foreign school society.

Contains mounted specimens of needlework.

Manual of the Lancasterian system, of teaching reading, writing, arithmetic, and needle-work, as practised in the schools of the Free-society, of New York.

"In the compilation of this work...the manual published in 1816, by the British and foreign school society...was carefully examined; such parts thereof adopted as were thought suitable, and alterations and additions made, calculated to render it a clear statement of the system as practised in New-York."--Pref.

Manual of the system of the British and foreign school society of London, for teaching reading, writing, arithmetic, and needle-work, in the elementary schools.

Mode of access: Internet.

Needle and thread, 1915-1960 : 45 years Amalgamated Clothing Workers of America.

Cover title.

Nitrogen fixation in alfalfa : responses to bidirectional selection for associated characteristics /

"Issued December 1981"--2d prelim. page.

Biology, ecology, and control of the lodgepole needle miner /

Includes bibliographical references (p. 36-38).

The diagnosis of glanders by complement fixation /

"April 7, 1911."

Austrian pine (Pinus nigra) and certain other species of pine disorder : Dothistroma needle blight /

"April 1974"

Biology and control of the pine needle-sheath miner, Zelleria haimbachi Busck (lepidoptera; hyponomeutidae) /

"April 1959."

Effect of salinity on growth, pigmentation, N2 fixation and alkaline phosphatase activity of cultured Trichodesmium sp

Trichodesmium sp. isolated from the Great Barrier Reef lagoon was cultured in artificial seawater media containing a range of salinities. Trichodesmium sp. actively grew over a wide range of salinities (22 to 43 psu) and hence can be classed as euryhaline. Maximum growth occurred with salinities in the range 33 to 37 psu. Chl a content and alkaline phosphatase activity were found to increase with salinity over the range 22 to 43 psu, but the N-2 fixation rate was reduced at salinities below and above the range for maximum growth. Growth in media exhibiting maximum growth was characterised by well-dispersed cultures of filaments, while significant aggregations of filaments formed in other media. It is proposed that the tendency for Trichodesmium filaments to aggregate in media with salinities outside the range for maximum growth is an opportunistic response to a deficiency of cellular nitrogen, which results from the reduced N-2 fixation rates, and the aggregation occurs in order to enhance the uptake of combined N released within the aggregates and/or the N-2 fixation within the aggregates.

Factors affecting N2 fixation by the cyanobacterium Trichodesmium sp. GBRTRLI101

Various factors affecting N-2 fixation of a cultured strain of Trichodesmium sp. (GBRTRLI101) from the Great Barrier Reef Lagoon were investigated. The diurnal pattern of N2 fixation demonstrated that it was primarily light-induced although fixation continued to occur for at least 1 h in the dark in samples that had been actively fixing N-2. N-2 fixation was dependent on the light intensity and stimulated more by white light when compared with blue, green, yellow and red light whereas rates of N-2 fixation decreased most under red light. Inorganic phosphorous concentrations in the lower range of treatments up to 1.2 muM significantly stimulated N-2 fixation and further additions promoted little or no increase in N-2 fixation. Organic phosphorous (Na-glycerophosphate) also stimulated N-2 fixation rates. Added combined nitrogen (NH4+, NO3-, urea) of 10 muM did not inhibit N-2 fixation in short-term studies (first generation), however it was depressed in the long-term studies (fifth generation). (C) 2003 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.

Simultaneous fixation using glutaraldehyde and osmium tetroxide or potassium ferricyanide-reduced osmium for the preservation of monogenean flatworms: An assessment for Merizocotyle icopae

Simultaneous fixation was investigated for a marine organism: the monogenean flatworm ectoparasite Merizocotyle icopae. Four protocols for primary fixation were compared: 3% glutaraldehyde alone in OAM cacodylate buffer for a minimum of 2 hours; 1% glutaraldehyde in combination with 1% osmium tetroxide, both in 0.1M cacodylate buffer, until tissues darkened (5-20 minutes); 1% glutaraldehyde in OAM cacodylate buffer in combination with 0.5% potassium ferricyanide-reduced osmium until tissues darkened (5-20 minutes); 1% glutaraldehyde in combination with 1% osmium tetroxide, both in 0.1M cacodylate buffer, for 30 minutes. The study confirms that the standard method for transmission electron microscopic fixation (first listed protocol) routinely applied to platyhelminths is optimal for ultrastructural preservation, but some simultaneous fixation methods (second and third listed protocols) are acceptable when rapid immobilization is needed. Scanning electron microscopic preparations may be improved using simultaneous primary fixation. (C) 2004 Wilcy-Liss, Inc.