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Colman R S - - 1976
Repetitive behaviors of six autistic children were observed under two conditions of background illumination. During two sessions, the room was illuminated by fluorescent light and during two other sessions, by equal intensity incandescent light. Subjects spent significantly more time engaged in repetitive behavior under fluorescent light. Previous research suggested that ...
Sisson T R - - 1976
Riboflavin in whole blood, G-6-PD activity in erythrocytes and amino acids in plasma of infants irradiated by broad and narrow spectrum blue fluorescent light were determined. Riboflavin was reduced by both types of light. Loss of G-6-PD activity during phototherapy with subsequent hemolysis was observed in some infants under each ...
Weckesser J - - 1976
Light has been used as a primary energy source in studies of tetracycline transport by Rhodopseudomonas sphaeroides. Accumulation of the antibiotic occurs in light, while efflux occurs in dark. Both fluorescence enhancement and radioisotopic tracing have been used to monitor transport. Km's obtained from both techniques are similar. Light-induced accumulation ...
Seibert M - - 1975
The effects of eight different narrow band-emitting fluorescent lamps (371-750 nm) and four commercial broad band-emitting fluorescent sources upon growth and shoot initiation in tobacco callus (Nicotiana tabacum var. Wisconsin 38) have been characterized. Wavelength and intensity are equally important parameters in determining morphogenic changes. Near ultraviolet light (371 nm) ...
Shannon I L - - 1975
Two experiments involving littermate cotton rats were conducted to determine the effect of cool-white fluorescent versus artificial sunlight environments on caries incidence. There were no significant differences in either the incidence or extent of caries associated with the different types of lighting. This contradicts our previous observations (1) with this ...
Brandtzaeg P - - 1975
Anionic-exchange fractions of IgG labeled with FITC, MRITC, RB200SC, or RBITC were tested on different substrates, and the resultant fluorescence was evaluated with the Ploem optical system. Conjugations with MRITC or RB200SC were found to afford the following advantages over FITC: immunofluorescence sensitivity was elevated six to seven times on ...
Schreiber UVidaver W - - 1975
With reduction of System II acceptors during dark anaerobic adaptation in Scenedesmus obliquus fluorescence yield rises to a maximum value in two distinct transitions. Subsequent illumination results in a decay of fluorescence yield with the following characteristics: 1. In low intensity light it is independent of temperature and is an ...
Bezanilla F - - 1975
1. Extrinsic fluorescence intensity changes were studied in frog semitendinosus muscles stained with Nile Blue A in response to electrical stimulation. Muscles were stretched and put into hypertonic solutions to prevent movement. The muscles were illuminated at 90 degrees to their long axis with a narrow beam of light at ...
Berger A - - 1975
For color matching and color measurement of fluorescent samples, artificial light sources are required that, have an irradiance distribution of maximum possible fit to that of the standard illuminant D65, even in the ultraviolet-wavelength range. Expanding an earlier study, calculations are made as to how much more information is obtained ...
Anders G - - 1975
In direct determination by fluorimetry the limits of detection are governed by the restricted light stability of fluorescent whitening agents (FWAs) in solution. The initial value of a fluorimetric reading can be registered by a rapid recorder, and in this way very light sensitive traces of FWAs as low as ...
Landi S - - 1975
The effect of light on the biologic potency of tuberculin purified protein derivative solutions at the concentrations commonly used in tuberculin skin testing programs in human and veterinary medicin was studied. Guinea pigs sensitized with bacille Calmette-Guerin were used to evaluate the potency of these solutions after exposure to light. ...
Krause G H - - 1974
Based on cation effects on chlorophyll a fluorescence and the light scattering behaviour of chloroplasts, a new interpretation of energy-dependent fluorescence quenching in intact leaves and isolated spinach chloroplasts is given. This type of fluorescence quenching is suggested to reflect movement of Mg2+ and other cations from the thylakoids to ...
Godfraind-de Becker A - - 1972
1. The time course of the aerobic recovery following a 0.5 sec tetanus at 20 degrees C of the sartorius muscle of the toad Bufo bufo, equilibrated in bicarbonate-CO(2) Ringer solution, has been followed by recording simultaneously the heat production and the fluorescence excited by ultra-violet light at 366 nm.2. ...
Ernst D - - 1971
Quantitative microfluorescence measurements often involve the integration of the fluorescent light over the field of view of the microscope. This can easily be done by simply directing the light onto the cathode of a photomultiplier as long as all the emitted light leaves the specimen without being absorbed. However, if ...
Cathey H M - - 1970
Flowering of chrysanthemum plants under short photoperiods, as is well known, is prevented when the plants are illuminated near the middle of the long night. Such illumination inhibits flowering whether it is given continuously or intermittently, and whether it comes from incandescent or from fluorescent lamps. We discovered, however, that ...
Perkins J H - - 1969
Reproductive differentiation in the basidiomycete Schizophyllum commune Fr. is initiated by plasmogamy and reciprocal nuclear migration and is terminated by the production of basidiospores. The work reported here has analyzed several factors that affect 2 sequential steps in reproductive differentiation: A) the formation of aggregated masses of cells, and B) ...
Munday J C JC - - 1969
The fluorescence transient of Chlorella pyrenoidosa, excited by saturating blue light, has a base level O, hump I, dip D, peak P, and at 1.5 sec a quasi-steady level S (12). With 2 sec exciting exposures and 4 min dark periods, preillumination-1 (lambda >/= 690 nm, intensities 1-750 ergs/sec-cm(2) incident), ...
Munday J C JC - - 1969
The fluorescence transient of Chlorella pyrenoidosa, excited by saturating light absorbed mainly by system II, has a dip D between the peak I at 75 msec and the large peak P at 400 msec (the times depend on light intensity). This dip is observed in aerobic cells and in anaerobic ...
Papageorgiou G - - 1968
he fluorescence yield of chlorophyll a in dark adapted Anacystis nidulans undergoes a slow change with continuous illumination. After the completion of the initial fast transient, the fluorescence yield rises from the level S to a plateau M within a minute, declining only after prolonged illumination. Both normal and 1,1-dimethyl-3(3'4'-dichloro)-phenylurea ...
Papageorgiou G - - 1968
The long-term fluorescence induction in Chlorella pyrenoidosa consists of a fast rise of the fluorescence yield from the level S (of the first wave transient) to a maximum M, followed by slower decay to a terminal stationary level T. The maximum M is attained within 40 seconds from the onset ...
Papageorgiou G - - 1967
The intensity of the "steady-state" fluorescence of "aerobic" Anacystis nidulans is variable under prolonged illumination with orange (590 mmu) or blue (440 mmu) light for both normally photosynthesizing and DCMU-poisoned cells. In general, orange light illumination causes an increase of the fluorescence intensity followed by a decrease, while blue light ...
Rogers A K - - 1966
Some ir transmitting materials fluoresce in the near ir spectral region when they are stimulated by visible light. An investigation of twenty-three different optical materials that might be used as elements in ir samples revealed that thirteen of these materials fluoresced to some degree. Quantitative measurements of the fluorescence were ...
Eastman J W - - 1966
A technique is proposed that can be used to calibrate the amplitude of fluorescence spectra so that spectra reported by different laboratories can be compared quantitatively. The technique is based upon the scattering of light by a solution of polystyrene. In order to compare quantitatively data obtained from different spectrofluorimeters, ...
CLAYTON R K - - 1965
Green photosynthetic bacteria exhibit variations in the intensity of their fluorescence during illumination. The initial intensity of fluorescence, measured at the onset of illumination, has a spectrum in which the major pigment Chlorobium chlorophyll predominates. The minor pigment bacteriochlorophyll predominates in the spectrum of the time-varying part of the fluorescence. ...
Brandt R - - 1963
Fundamental fluorescence equations were examined. Deviations from the theoretical were observed by varying the light path length to determine effects on "apparent" fluorescence. It was found that the decrease in emission of morphine solutions with the increase in concentration was caused by absorption effects that prevented excitation of the whole ...
Drujckrey H - - 1955
In the issue of 2 September, page 421, the address of Hermann Druckrey, coauthor of the paper "Light-dependence of fluorescence of solutions of cigarette smoke," was incorrectly given as Sloan-Kettering Institute for Cancer Research, New York. Dr. Druckrey's address is Chirurgische Universitäts-Klinik, Hugstetterstrasse 55, Freiburg im Breisgau, Germany.
ARNOLD W - - 1954
1. The delayed light emission of Chlorella pyrenoidosa over the wave length range 400 to 950 mmicro has been investigated. 2. Emission of delayed light is confined to the range 600 to 800 mmicro. 3. To the precision with which the low light intensities involved can be measured with the ...
Harvey E N - - 1925
1. Small dumps of the luminous cells of Mnemiopsis cannot readily be stimulated mechanically but will luminesce on treatment with saponin solution. Larger groups of luminous cells (such as are connected with two paddle plates) luminesce on mechanical stimulation. This suggests that mechanical stimulation to luminesce occurs chiefly through a ...
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