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The article presents the author's view on the development of meteorological knowledge about Antarctica. He says that the question of world-wide pollution is a pressing one and promises to become even more serious and the increase of carbon dioxide, DDT and lead in Antarctica indicates that it is becoming contaminated by man-made pollutants. He emphasizes that it is time to establish stations to measure all aspects of this contamination in order to provide a base line against which to compare future conditions.

A method for producing flexible silicone rubber casts of the airways of the lungs in‐situ is described. Casts are made to correspond to lung volumes occurring during normal breathing. The lung is prepared for casting by replacing the air within with CO2 followed by filling with degassed physiological saline. The saline dissolves the CO2 gas within the airways allowing for a bubble‐free finished cast. Casting compound is then slowly injected through the trachea. The saline diffuses out of the lung and passes out of the thorax through several small slits in the thoracic wall. After the injection is completed, the cast lung is allowed to cure in‐situ before it is removed and the tissue digested away. Finished casts have an overall shape corresponding closely to the shape of the thorax. Casts produced by this in‐situ method appear to have more realistic geometrical relationships than those produced from excised lungs. Copyright © 1973 Wiley‐Liss, Inc.

A new rapid assay for phosphatidylserine decarboxylase, which is sensitive in the nanomolar range, is described. Synthesis of radiolabeled phosphatidylserine for use as a substrate is not required, since the assay, unlike previous ones, is based on the detection of CO(2) liberated from unlabeled phosphatidylserine. The assay employs a gas chromatographic procedure for the analysis of methane formed by catalytic conversion of the CO(2) produced as a product of the enzymatic reaction.

The blood supply to several regions of the chick brain is rapidly decreased following reduction of visual input by monocular eyelid Suture. This decrease is not confined to the primary visual area (the optic lobe) contralateral to and innervated by the sutured eye but is also apparent in the indirectly innervated cerebral hemispheres contralateral to the treated eye. After periods of bilateral eyelid suture, exposure of a single eye to patterned light by suture removal results in a rapid increase of blood flow through contralateral cerebral regions directly or secondarily innervated by the exposed eye. This response appears to be more closely related to the intensity rather than to the information content of incident light. The ability to regulate regional cerebral blood flow is lost following reduction of brain catecholamine levels with reserpine. However, cerebral blood flow is still responsive to afferent sensory input, in the presence of a concentration of carbon dioxide sufficient to cause near maximal dilation of cerebral blood vessels. This suggests that variations of vascular supply to specific brain regions may in part be effected by direct autonomic nervous mechanisms regulating the diameter of blood vessels within the brain. © 1973.

Examination of the effect of CO2-concentration and time of day on the content of malic acid, citric acid, aconitic acid, isocitric acid, succinic acid and fumaric acid in tomato leaves, revealed that the total content of these acids will rise with the CO2-concentration up to 0.10 vol% Co2. In the morning up to 0.22 vol% CO2 was needed for optimal effect. Samples of leaves picked at 1 a.m. showed the lowest content of these acids. At 9 a.m. the content had increased, and at 4 p.m. the increase was considerable. The content of malic and citric acid constituted 36 and 34% of the total acid content. In the afternoon and the night the aconitic acid represented 14% and in the morning 20% of the total acid content. Isocitric acid, fumaric acid and succinic acid occurred only in relatively small concentrations. [ABSTRACT FROM AUTHOR]

Four mosses, Bryum argenteum, Grimmia pulvinata, Hypnum cupressiforme and Tortula muralis were exposed to sulphite, and their uptake of radioactive bicarbonate measured. About 50% reduction in 14C uptake was caused by 0.01-0.1 mM suiphite. The effect of pH indicated that SO2 (or H2SO3') was the active molecular species. Fluoride had little effect on 14C uptake. [ABSTRACT FROM AUTHOR]

The effect of sodium azide upon the stomatal behaviour in excised leaves of Stachytarpheta indica was studied by microscopic examination of epidermal strips fixed in absolute ethanol. Azide was found to retard stomatal opening on both Illumination of rurgid leaves and wilting of excised leaves ; it did not, however, affect stomatal closure. Carbon dioxide-free air was effective in compensating the azide effect. It appears that, in addition to the leaf water balance, changes in the rates of such processes as photosynthesis resulting from lea excision also have controlling effects on stomatal movements by disturbing the level of carbon dioxide in the intercellular spaces and it is concluded that azide may retard stomatal opening by its effect on these processes. Changes in starch in the guard cells apparently play a subsidiary role in these stomatal responses. [ABSTRACT FROM AUTHOR]

Uninfected plantlets of Goodyera repens and plantlets infected with the endophyte Rhizoctonia goodyerae-repentis were fed with 14CO2. Quantities of 14C fixed varied greatly between individuals, but there was a consistent pattern of distribution of label which remained unaltered over four weeks. Very little 14C moved to the rhizomes. The endophytic fungus readily grew from infected plantlets on to Pfeffer agar and small amounts of radioactivity were found in the mycelium growing from previously fed plantlets. 14C leakage from uninfected plantlets was negligible, although low levels of radiactivity occurred in serial washings from them. When the tops alone of infected plants were fed with 14CO2, no radioactivity could be detected in the emerging fungal mycelium. Where rhizomes alone were exposed, small quantities of 14C were detected in the growing mycelium. The fungus readily translocated 14C from the remains of dead protocorms. It appears that R. goodyerae-repentis does not freely utilize recent photosynthate from its host under the conditions of these experiments. [ABSTRACT FROM AUTHOR]

Both morphological forms of Phaeodactylum tricornutum incorporated acetate in the light and in darkness. In the dark, the majority of the acetate was oxidized, probably by the tricarboxylic acid cycle. Although some CO[SUB2] was formed from acetate in the light, most acetate carbon was found in the cellular lipids. Acetate incorporation in the light was probably a result of both direct and indirect assimilation. The organism grew poorly an acetate in the light at a very low CO[SUB2] tension. [ABSTRACT FROM AUTHOR]

Daily patterns of incorporation of carbon dioxide and inorganic phosphate were measured in phytoplankton from Lake George, New York, in January and February 1972. Rates of photosynthesis oscillated in phase for the entire assemblage and for individual cells of the diatoms Asterionella, Tabellaria, and Fragilaria. The photosynthetic capacity was maximal in the early afternoon. Daily patterns of phosphate uptake were also rhythmic. At ambient concentrations the assemblage takes up phosphate maximally in the morning while individual cells of the large diatom take it up maximally in the evening. A kinetic analysis of phosphate uptake indicated 2 velocities of uptake for cells of Tabellaria and Fragilaria: a hyperbolic function at small and an apparently linear relationship at relatively large concentrations. The large diatoms, in contrast to the total assemblage, functioned maximally at 2 separate times of the day: in the evening at ambient levels and in the morning at 0.4 μm and larger concentrations. Temporal stratification of the nutrient niche may be achieved by several uptake mechanisms in the algal cell that function at different times of the day or with a variable uptake velocity. [ABSTRACT FROM AUTHOR]

The excretion of glycolic acid by the marine diatom Chaetoceros socialis through time was studied. Excreation in axenic cultures was linear for the time intervals used, but for nonaxenic cultures an equilibrium was created, suggesting bacterial uptake of glycolic acid. In studies with an inhibitor of glycolate dehydrogenase, the level of glycolic acid in the medium jumped 15-fold. This shows the presence of the entire set of enzymes which convert glycolic acid to serine and release carbon dioxide. In both axenic and nonaxenic cultures a steady state was reached. All of the data suggest that at high cell densities glycolic acid is liberated from the cell by a passive mechanism. The effect of such an excretion in natural waters is discussed. [ABSTRACT FROM AUTHOR]

The Bohr effect related to whole blood ( Be) and erythrocyte pH ( Bi) was determined over a wide oxygen saturation range at an almost constant 2,3-diphosphoglycerate concentration. In two different sets of experiments acidification was caused either by fixed acid (lactic acid) or by CO. Fixed acid-induced Bohr coefficients can be approximated by a second-order function of O saturation with a maximum at mid-saturation range. CO-induced Be and Bi values yield a third-order relationship with highest results at low O saturation. The ratio Bi/Be with respect to fixed acid-acidification exhibits a positive correlation with oxygenation, whereas the corresponding ratio referring to CO does not. For this different behavior a possibly more pronounced diminution of the Haldane effect, i.e. oxygen-linked proton release, in the presence of fixed acid is discussed. The physiological importance of the magnitude of CO-induced Bi values at low O saturation is emphasized. [ABSTRACT FROM AUTHOR]

Twenty-five patients with acne conglobata were treated with cryotherapy delivered via probes. The probe was applied to nodular lesions for 20-25 s without pressure. Freon, carbon dioxide and nitrous oxide were found to be therapeutically equivalent. Nodulo-cystic lesions resolved within 7-10 days leaving a thin atrophic scar on the back and no scar on the face. The treatment was almost painless; no recurrence has appeared in the treated areas. [ABSTRACT FROM AUTHOR]

Water loss and carbon dioxide release measurements were performed to determine whether the severity of damage to human skin, caused by exposing its surface to buffered and unbuffered solutions of alkah and sodium phosphate, could be evaluated simultaneously by means of different measuring techniques and whether the results of these measurements, expressed in numerical terms, gave identical information. It appeared that the buffered solutions disturbed skin functions less than the unbuffered solutions and therefore may be considered to be less harmful. The NaOH solution at pH 12.0, lacking any buffering capacity, damaged the skin, producing signs of inflammation, whereas that at pH 10.0 did not. It appeared that skin damage could be assessed reliably by simultaneously measuring changes in skin impedance, water loss and carbon dioxide release, which are interrelated parameters. [ABSTRACT FROM AUTHOR]

The spontaneous upstream swimming of goldfish ( N=1318) into a quiet well was suppressed in one trial by electric shock (2.0 V/cm). Independent groups of fish, at 25‡ C, retained this learned avoidance 1, 4, 16, and 64 h after training but not 256 h after training. When trained fish were treated, 3 min after training, with a 16-min exposure to convulsive solutions of flurothyl (Indoklon®), their retention of avoidance 16, 64, or 256 h later was facilitated. This retroactive facilitation (RF) of long-term memory in goldfish by flurothyl could not be attributed to proactive or aversive effects of the treatment. Goldfish treated in water saturated with carbon dioxide (80% CO∶20% O) showed retrograde amnesia (RA). Neither the RF from flurothyl nor the RA from CO-treatment were diminished when training and treatment were given to goldfish at 20‡ or 15‡ C. The memory-enhancing effect of flurothyl convulsions, and its delayed onset, may relate to the dual stimulant-depressant action of the drug and differ from the RA effect reported for mice and chicks. [ABSTRACT FROM AUTHOR]

This paper reports on seasonal cycles of physical and chemical factors, over a period of two years, which were expected to affect the size and seasonal variation of phytoplankton production in the eutrophic, dimictic Lake Esrom, Denmark. Insolation, transparency, temperature, oxygen, total carbon dioxide, free carbon dioxide, pH, alkalinity, silicate, nitrate, ammonia, orthophosphate and total phosphate, were measured to describe the lake hydrography. They are presented as isopleths. After the spring maximum of phytoplankton, nitrogen and silica rapidly declined to insignificant and limiting concentrations while phosphate- phosphorus declined to 50% (150 μg litre-1) of the winter value. Light can limit phytoplankton production at all seasons. A phosphorus balance showed that there was about 80 t of phosphorus in the lake. Phoshorus recycled in the lake ecosystem was 20 t, 10 t from tributaries and 10 t annually being added to the sediment. The evidence for enrichment includes a discussion on the history of the lake, coring, ground water analyses, changes in hypolimnetic dissolved oxygen, and changes in transparency. The possible influence of pollution from sewage is discussed in relation to the estimated nutrient budget of nitrogen and phosphorus. Increase in nutrients failed to increase phytoplankton production during 17 years. [ABSTRACT FROM AUTHOR]

A system is described for measuring in situ CO2 evolution rates from forest soil. The apparatus incorporates an infrared gas analyzer with open air flow through 10 chambers which sequentially lower over the forest floor during measurements and raise after measurements are complete. Unlike methods using stationary chambers, this system allows litter and soil horizons to undergo a natural drying cycle. Litter moisture under stationary chambers was 76% of dry weight at the end of a 3-day sample period as compared to 40% under moving chambers and 39% in control plots. Carbon dioxide evolution rates from plots enclosed by stationary chambers ranged from 54 to 90% higher than those from moving chamber plots. Effects of such discrepancies in calculating the carbon balance of forest ecosystems are discussed. Application of the moving chamber apparatus in monitoring gaseous losses from biodegradable waste such as by-products of petroleum is also discussed. [ABSTRACT FROM AUTHOR]