Search

Desulfovibrio vulgaris was shown to be capable of utilizing a BaSO4 precipitate as a sulfate source. The δ34S values of the evolved sulfide ranged from -4.8‰ to +6.2‰ with respect to the BaSO4 and appeared to depend upon the amount of dissolved sulfate (>10-5M) present at any given time.

Abstract: In no-choice tests but not in choice tests, alligatorweed flea beetles,Agasicles hygrophila Selman & Vogt (Col.: Chrysomelidae) exposed to alligatorweed plants grown with two levels of mineral nutrition fed significantly more on those grown in full mineral nutrient than those grown with deficient phosphate. Chemical analysis showed that the full nutrient plants had more ethanol-soluble nitrogen compounds but less total carbohydrate than the phosphate-deficient plants. The response of beetles to phosphate-deficient alligatorweed may thus result from a change in the carbohydrate-nitrogen composition of host plants, though further investigation is needed for confirmation. Flea beetle response was identical to terminal and mature leaf tissue of full nutrient plants.

The data obtained in these preliminary experiments clearly demonstrate that a bacteria and nutrient top-dressing is capable of generating anaerobiosis and of increasing pH. These changes appear to correspond to the depths at which increases in the bacterial population are noted. This suggests that the bacterial population had utilized the available oxygen, and had promoted anaerobic conditions and reduced acid production by plugging the available pore spaces through cell growth and exopolymer production. This interpretation is strongly supported by the reduction in permeability noted after top-dressing with bacteria and nutrient.

Four strains of Desulfovibrio produced ammonium during growth on a defined medium containing 100 µg NO3--N/ml in the presence of 1 mM sulfate. Ammonium was not produced by cultures grown in media devoid of sulfate nor in media containing 35 mM sulfate. The four strains of Desulfovibrio studied reduced 32.7–46% of the available nitrate to ammonium in 21 days incubation. Ammonium production from nitrate was confirmed by recovering 15N-enriched ammonium when 15N-enriched Ca(NO3)2 was utilized as the substrate for the reduction.

Abstract: Solids content and amylose/amylopectin ratios were determined in different parts of tubers of White Rose, Red La Soda, Kennebec, Russet Burbank, Norchip and Lenape at harvest, after storage at 7 C for 2 and 4 mo, and after reconditioning at 20 C for 3 wk following each storage period. In all cultivars, solids content was greatest in stem-end, lower in bud-end and lowest in core tissue. The relationships for distribution of solids among the different parts of the tubers was not changed by storage treatments in any of the cultivars. Amylose/amylopectin ratios were similar in all parts of the tuber. Both the solids content and amylose/amylopectin ratio were changed by storage, but not uniformly in all cultivars.

Summary A drop-scale modification of the common volumetric lactic acid method is described. Samples containing from 1,22 to 28,85? of lactic acid were analysed in simple solutions and in various blood samples. The accuracy of the method was usually about the same as in the macro procedure.

The antibacterial activity of aqueous solutions of paraformaldehyde in concentrations from 0.1 to 0.4% (w/v) is bacteriostatic rather than bactericidal in the presence or absence of ammonium chloride. The presence of ammonium chloride significantly lengthened the time of exposure to paraformaldehyde necessary for inhibition of growth of the test organism (Staphylococcus aureusFDA 209) when unbuffered solutions were used. Elevation of the pH of the reacting mixture of paraformaldehyde and ammonium chloride by partial buffering lengthened the time of exposure necessary for inhibition of growth of the test organism. Decrease of antibacterial activity was concomitant with the disappearance of paraformaldehyde from the reacting mixture. The reaction of paraformaldehyde with ammonium chloride was rapid at room temperature (25 C) and at pH levels near neutrality. The fate of the reacting paraformaldehyde, including the possibility of the formation of hexamethylenetetramine or methylenimine, is discussed with particular reference to loss of antibacterial activity.

Abstract: The annual processing of citrus fruit wastes in the United States has reached two million tons. Forty thousand tons of pectin could be produced, compared with current production of three thousand tons. The physical and chemical properties of pectic substances are important botanically and industrially. Pectic substances aid in maintaining texture of fruits and vegetables and serve as jellying agents in preserves. The availability of increasing amounts of citrus wastes, combined with improvements in manufacturing techniques and new uses, promises expansion of industries concerned with pectin production and utilization.

Two common environmental pollutants are agricultural residues (skins, pits, husks, tannin bark, grape pomace) and waste streams of water containing only traces of heavy metals (such as mercury at 10 or more ppb) from mining or manufacturing operations. Agricultural residues contain tannins, polyphenolic substances, pectin, and other polymers—all with chemically reactive groups that can chelate, reduce, oxidize, demonstrate ion exchange properties, and aid in removing traces of heavy metals from dilute waste water streams at low cost. Finely ground and water‐washed agricultural residues were slurried in water and packed into columns for absorption tests with heavy metals. Solutions of known concentrations of heavy metals were passed through the packed columns which were then eluted with water or with alkaline or acidic solutions. The fractions and the column absorbents were then analyzed by standard atomic absorption methods. The nature of the physical and chemical forces that are effective in metal absorption from agricultural residues is not clear.

not available

IntroductionEndoscopic ultrasound (EUS) guided drainage is now the first line treatment for drainage of symptomatic pancreatic pseudocysts. This study investigates the effects of metal vs. plastic transmural stents. The primary outcome measure was defined as rate of reintervention for pseudocyst following stent.MethodA prospectively maintained database from 2011–2016 was analysed. Fluid collections were characterised by CT imaging and EUS. All patients were discussed at multidisciplinary meeting prior to intervention.Results74 patients with pseudocysts were included in this analysis. There was no significant difference in patient demographics or indication for intervention between the groups. Metal stents were placed in 38 (51%) patients. Three patients (8%) with metal stents required further intervention compared to 11 patients (31%) with plastic stents (p=0.037). Technical success was similar between groups; 100% for metal vs 97% for plastic stents. At 6 weeks following procedure, pseudocyst drainage was achieved in 33/35 patients using metal vs 27/36 of the plastic stent group (p=0.046). 25 patients with metal stents achieved pseudocyst drainage at 6 months vs 23 (p=0.25) who had plastic stents. Early adverse events were less common in the metal stent group (8%) vs 33% with plastic stents (p=0.009).ConclusionUse of metal transmural stents for drainage of pancreatic pseudocysts may reduce reintervention rates and causes fewer adverse events compared to plastic stents. Drainage with metal stents is most effective by 6 weeks, with little difference between metal vs. plastic stents by 6 months.Disclosure of InterestNone Declared

The classic Kjeldahl procedure for determing protein (nitrogen) in oilseed meals is satisfactory but too time consuming for quality control in plants handling large amounts of meal. This paper describes attempts to decrease the time required for nitrogen analysis of safflower seed and meal using equipment available in the quality control feeds laboratory. A dye-binding method on undigested proteins, digestion followed by colorimetric ammonium determination, digestion followed by distillation of ammonia, and several different digestion catalysts were tested. Digestion with the AOAC catalysts for 15 min and distillation of ammonia for 10–15 min for 90 ml of distillate followed by titration gave results on safflower meals in agreement with the AOAC method and is recommended for accelerated protein tests.

The classic Kjeldahl procedure for determing protein (nitrogen) in oilseed meals is satisfactory but too time consuming for quality control in plants handling large amounts of meal. This paper describes attempts to decrease the time required for nitrogen analysis of safflower seed and meal using equipment available in the quality control feeds laboratory. A dye-binding method on undigested proteins, digestion followed by colorimetric ammonium determination, digestion followed by distillation of ammonia, and several different digestion catalysts were tested. Digestion with the AOAC catalysts for 15 min and distillation of ammonia for 10–15 min for 90 ml of distillate followed by titration gave results on safflower meals in agreement with the AOAC method and is recommended for accelerated protein tests.

A recent survey demonstrated that about 70 of patients attending a cancer hospital were taking alternative medicines (CAMs). These medicines included herbal remedies, food supplements, vitamin preparations and various other organic and inorganic substances which could potentially affect the uptake and retention of radiopharmaceuticals.

The yearbooks in various subjects will be familiar to most readers. This year's yearbook on Nuclear Medicine follows the usual format of previous years and of the other subjects. The lead article this year concerns the challenge of computerized axial tomography to nuclear medicine imaging. Dr. Michel Ter-Pogossian is an extremely suitable person to write this article since he is involved with tomographic imaging of all kinds.