The oceans have absorbed nearly half of the fossil-fuel carbon dioxide (CO2) emitted into the atmosphere since pre-industrial times, causing a measurable reduction in seawater pH and carbonate saturation. If CO2 emissions continue to rise at current rates, upper-ocean pH will decrease to levels lower than have existed for tens of millions of years and, critically, at a rate of change 100 times greater than at any time over this period. Recent studies have shown effects of ocean acidification on a variety of marine life forms, in particular calcifying organisms. Consequences at the community to ecosystem level, in contrast, are largely unknown. Here we show that dissolved inorganic carbon consumption of a natural plankton community maintained in mesocosm enclosures at initial CO2 partial pressures of 350, 700 and 1,050 microatm increases with rising CO2. The community consumed up to 39% more dissolved inorganic carbon at increased CO2 partial pressures compared to present levels, whereas nutrient uptake remained the same. The stoichiometry of carbon to nitrogen drawdown increased from 6.0 at low CO2 to 8.0 at high CO2, thus exceeding the Redfield carbon:nitrogen ratio of 6.6 in today's ocean. This excess carbon consumption was associated with higher loss of organic carbon from the upper layer of the stratified mesocosms. If applicable to the natural environment, the observed responses have implications for a variety of marine biological and biogeochemical processes, and underscore the importance of biologically driven feedbacks in the ocean to global change.

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Twelve water and/or mud samples from different mosquito habitats were tested for the presence of phages specific to Bacillus spp. Thirty seven plaque morphologies were detected on B. thuringiensis H‐14, B. thuringiensis Berl., B. sphaericus 1593, B. sphaericus IF‐114. Samples number 1, 11, 12, 5 and 10 decreased the mortality rates of B. thuringiensis H‐14 when added to the larvicidal bioassay system of Culex pipiens. Samples number 5, 11, 9, 12 and 6 inhibited the larvicidal activity of B. sphaericus. Ultrafiltrates of water samples, which harboured high numbers of the detected phages exerted more inhibition in the larvicidal potentiality of the tested entomopathogenic bacteria. Zusammenfassung Zur Wirksamkeitsreduktion von Bacillus thuringiensis und B. sphaericus durch das Auftreten von Bakteriophagen in Moskito‐Habitaten In verschiedenen Moskitogebieten wurden insgesamt 12 Wasser‐ bzw. Schlammproben entnommen und auf Bacillus‐spezifische Phagen untersucht. Bei Bacillus thuringiensis H‐14, B. thuringiensis Berl., B. sphaericus 1593 und B. sphaericus IF‐114 wurden 37 Plaques gefunden Die Phagen aus 5 Proben (1, 11, 12, 5, 10) reduzierten die larvizide Wirkung des B. thuringiensis‐Einsatzes gegen Culex pipiens. Phagen aus den Proben 5, 11, 9, 12 und 6 verhinderten die larvizide Wirkung von B. sphaericus. Ultrafiltrate der Wasserproben, die eine hohe Anzahl der entdeckten Phagen enthielten, zeigten eine noch deutlichere Reduktion der larviziden Wirkung der untersuchten entomophagen Bakterien.

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The effect of some insulinotrophic drugs on the transport of sugar was investigated in fasted, narcotized rats by continuous perfusion of cannulated long intestinal loops with galactose solution (18 mM.) circulated by air lift. Three consecutive perfusions (fifty minutes each) were performed in each rat, the drug being given in the second perfusion only. The rate of galactose disappearance was expressed as per cent of that in the first perfusion in the same rat.Tolbutamide (50 mg./l kg. weight), glycodiazine (50 mg./l kg. weight), glisoxepid (BAY 4231, 2 mg./l kg. weight) and glibenclamide (0.25 mg./l kg. weight) were found to increase the rate of galactose disappearance in the second perfusion by 21 per cent, 5 per cent, 12 per cent and 25 per cent, respectively, and in the third perfusion by 21 per cent, 26 per cent, 32 per cent and 21 per cent, respectively, as compared to the rate in the corresponding perfusion of a control group. This increase was significant (P values < 0.05) with all drugs in the second and third perfusions with the exception of glisoxepid in the second perfusion. These results are discussed in relation to the action of insulin and the effect of diabetes on intestinal absorption of sugars. DIABETES 23: 112-16, February, 1974. In a previous work, 1 we showed that metformin, an oral hypoglycemic agent of the biguanide group, markedly inhibited the transport of glucose by everted sacs of guinea pig intestine. In a later report, Kruger et al. , 2 using the same technic in rats, demonstrated a similar effect with phenformin.It seemed of interest to investigate the effect of the other group of oral hypoglycemics on the transport of sugar by the intestine. To the best of our knowledge, there were no reports in the literature concerning this point. The drugs selected for the present study were: tolbutamide (Rastinon), glycodiazine (Lycanol), glisoxepid (BAY 4231) and glibenclamide (Daonil).The present paper describes the effect of these insulinotrophic drugs on the transport of sugar by long intestinal loops continuously perfused in situ.

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