ALBERT

Notes: Summary Interaction of positively (phosphatidylcholine/stearylamine 5∶1) or negatively (phosphatidylcholine/stearic acid 5∶1) charged liposomes with Ehrlich ascites tumor cells for 1–5 min increases or decreases, respectively, the bidirectional fluxes of the folic acid analog, methotrexate. These effects on influx and efflux appear to be symmetrical since the liposomes do not change the intracellular level of methotrexate at the steady state. Influx kinetics show that these alterations result from an increase or decrease in theV max with no change in theK m in . These effects appear to be specific for the methotrexate-tetrahydrofolate carrier system since the transport of other compounds which utilize this carrier, aminopterin, 5-methyltetrahydrofolate, and 5-formyltetrahydrofolate, is affected similarly to methotrexate, whereas, the transport of folic acid, a compound similar in structure and charge but not significantly transported by this carrier is unaffected by liposomes. Once cells are exposed to charged liposomes, the effects on methotrexate transport cannot be reversed by washing the cells free of the extracellular liposomes. If, however, cells are exposed to liposomes of one charge, washed and then exposed to liposomes of the opposite charge, methotrexate influx is reversed to control rates. The effects of charged liposomes on methotrexate influx were not abolished by treating the cells with neuraminidase, metabolic inhibitors or lowering the temperature to 4°C. Studies on the uptake of [14C] liposomes show that these effects are not proportional to the total amount of lipid associated with the cell but result from an initial rapid liposome-cell association that is not dependent on temperature or energy metabolism nor related to cell surface charge.

Notes: Abstract Seasonal and regional variations in the speciation, sediment-water partitioning, and dynamics of mercury (Hg) were studied at selected sites along the Hg-polluted Wabigoon River, and at unpolluted headwater and tributary sites, during April–September, 1979. ‘Dissolved’ and ‘particulate’ forms of Hg in the water were separated by continuous-flow centrifugation in the field. The Hg and other pollutants such as wood chips and salt had been discharged from a chlor-alkali plant and paper mill at Dryden, Ontario. Concentrations and loadings of particulate methyl mercury (CH3Hg+) and total particulate Hg (and loadings of total ‘dissolved’ Hg) were greatest during the spring flood (April-May) owing to accelerated resuspension and transport of sediments. Concentrations of ‘dissolved’ CH3Hg+, however, were highest in the summer (July–September), probably reflecting stimulation of microbial methylating activity by elevated temperatures, together with factors such as reduced levels of metal-scavenging particulates and minimal dilution by runoff. Total dissolved Hg concentrations were relatively high in September at polluted sites only, possibly because of desorption from sediments due to elevated concentrations of Cl− ions. Loadings of dissolved CH3Hg+ tended to be high in the summer but were generally depressed (suggesting sorption by suspended particles) during the major spring-flood episode in May. During July–August dissolved CH3Hg+ was a function of total dissolved Hg, suggesting rapid biomethylation of desorbed inorganic Hg; but in general dissolved and suspended CH3Hg+ levels depended on environmental variables and were unrelated to total Hg concentrations. In the summer only, total dissolved Hg was a function of dissolved Cl−. Hg species in particulates were associated with sulfides, hydrated Fe and Mn oxides, organic matter (notably high molecular weight humic and humic-Fe components), and selenium (Se); but CH3Hg+ and total Hg differed in their specific preferences for binding agents, implying that binding sites discriminate between CH3Hg+ and Hg2+ ions. CH3Hg+ was associated with sulfide and (in the spring only) with Fe oxides, whereas total Hg was associated with organic matter and Se and with DTPA- and NaOH-extractable Fe in the spring but with Mn oxide and NaOH-extractable organics in the summer. Sulfides were most abundant in May, indicating that they were eroded from bottom sediments, but Fe and Mn oxides were most abundant in the summer, probably owing to activities of filamentous iron bacteria and other micro-organisms. Particulate Hg was 98–100% nonextractable by mild solvents such as Ca acetate, CaCl2, dilute acetic acid, and (at polluted sites only) DTPA solutions, suggesting that the particulate Hg mobilized in the spring may not be readily available to organisms; association with Se and high molecular weight humic matter also supports this hypothesis. Hg probably becomes more bio-available in the summer, as suggested by the upsurge in dissolved CH3Hg+ and total dissolved Hg levels, and by increases in the solubility of particulate Hg in acetic acid, DTPA, H2O2, and NaOH solutions, as well as an increase in the relative importance of lower molecular weight fractions of NaOH-extractable Hg (in September). Regional variations in Hg speciation and partitioning reflected a gradient in sediment composition from wood chips near Dryden to silt-clay mud further downstream. Hg in silt-clay mud relatively far (〉 35 km) downstream from the source of pollution or in unpolluted areas appeared to be more readily solubilized by Cl− ions or chelators such as DTPA, more readily methylated (as indicated by downstream increases in dissolved CH3Hg+ levels and CH3Hg+/total Hg ratios), and was to a greater degree organically bound (H2O2-extractable), and thus was probably more bio-available, than Hg in wood-chip deposits. Possible explanations include weaker binding of Hg by the mud, the more finely divided state of the mud, and improved microbial growth at lower concentrations of toxic pollutants. Owing to enrichment in sulfides and Fe oxides, resuspended wood-chip sediments were especially efficient scavengers of CH3Hg+. The results indicate that in any pollution abatement plan aimed at lowering the Hg levels in the biota of lakes fed by the Wabigoon River, immobilization, removal, or detoxification of dissolved as well as particulate forms of Hg in the river would probably have to be considered. Possibly, Hg species could be ‘scrubbed’ from the river water by increasing the suspended load and by sedimentation and treatment with Hg-binding agents in special receiving basins.

Notes: Abstract Seasonal and regional variations in the speciation, sediment-water partitioning, and dynamics of mercury (Hg) were studied at selected sites along the Hg-polluted Wabigoon River, and at unpolluted headwater and tributary sites, during April–September, 1979. ‘Dissolved’ and ‘particulate’ forms of Hg in the water were separated by continuous-flow centrifugation in the field. The Hg and other pollutants such as wood chips and salt had been discharged from a chlor-alkali plant and paper mill at Dryden, Ontario. Concentrations and loadings of particulate methyl mercury (CH3Hg+) and total particulate Hg (and loadings of total ‘dissolved’ Hg) were greatest during the spring flood (April-May) owing to accelerated resuspension and transport of sediments. Concentrations of ‘dissolved’ CH3Hg+, however, were highest in the summer (July–September), probably reflecting stimulation of microbial methylating activity by elevated temperatures, together with factors such as reduced levels of metal-scavenging particulates and minimal dilution by runoff. Total dissolved Hg concentrations were relatively high in September at polluted sites only, possibly because of desorption from sediments due to elevated concentrations of Cl− ions. Loadings of dissolved CH3Hg+ tended to be high in the summer but were generally depressed (suggesting sorption by suspended particles) during the major spring-flood episode in May. During July–August dissolved CH3Hg+ was a function of total dissolved Hg, suggesting rapid biomethylation of desorbed inorganic Hg; but in general dissolved and suspended CH3Hg+ levels depended on environmental variables and were unrelated to total Hg concentrations. In the summer only, total dissolved Hg was a function of dissolved Cl−. Hg species in particulates were associated with sulfides, hydrated Fe and Mn oxides, organic matter (notably high molecular weight humic and humic-Fe components), and selenium (Se); but CH3Hg+ and total Hg differed in their specific preferences for binding agents, implying that binding sites discriminate between CH3Hg+ and Hg2+ ions. CH3Hg+ was associated with sulfide and (in the spring only) with Fe oxides, whereas total Hg was associated with organic matter and Se and with DTPA- and NaOH-extractable Fe in the spring but with Mn oxide and NaOH-extractable organics in the summer. Sulfides were most abundant in May, indicating that they were eroded from bottom sediments, but Fe and Mn oxides were most abundant in the summer, probably owing to activities of filamentous iron bacteria and other micro-organisms. Particulate Hg was 98–100% nonextractable by mild solvents such as Ca acetate, CaCl2, dilute acetic acid, and (at polluted sites only) DTPA solutions, suggesting that the particulate Hg mobilized in the spring may not be readily available to organisms; association with Se and high molecular weight humic matter also supports this hypothesis. Hg probably becomes more bio-available in the summer, as suggested by the upsurge in dissolved CH3Hg+ and total dissolved Hg levels, and by increases in the solubility of particulate Hg in acetic acid, DTPA, H2O2, and NaOH solutions, as well as an increase in the relative importance of lower molecular weight fractions of NaOH-extractable Hg (in September). Regional variations in Hg speciation and partitioning reflected a gradient in sediment composition from wood chips near Dryden to silt-clay mud further downstream. Hg in silt-clay mud relatively far (〉 35 km) downstream from the source of pollution or in unpolluted areas appeared to be more readily solubilized by Cl− ions or chelators such as DTPA, more readily methylated (as indicated by downstream increases in dissolved CH3Hg+ levels and CH3Hg+/total Hg ratios), and was to a greater degree organically bound (H2O2-extractable), and thus was probably more bio-available, than Hg in wood-chip deposits. Possible explanations include weaker binding of Hg by the mud, the more finely divided state of the mud, and improved microbial growth at lower concentrations of toxic pollutants. Owing to enrichment in sulfides and Fe oxides, resuspended wood-chip sediments were especially efficient scavengers of CH3Hg+. The results indicate that in any pollution abatement plan aimed at lowering the Hg levels in the biota of lakes fed by the Wabigoon River, immobilization, removal, or detoxification of dissolved as well as particulate forms of Hg in the river would probably have to be considered. Possibly, Hg species could be ‘scrubbed’ from the river water by increasing the suspended load and by sedimentation and treatment with Hg-binding agents in special receiving basins.

Notes: Abstract Seasonal and regional variations in the speciation, sediment-water partitioning, and dynamics of mercury (Hg) were studied at selected sites along the Hg-polluted Wabigoon River, and at unpolluted headwater and tributary sites, during April–September, 1979. ‘Dissolved’ and ‘particulate’ forms of Hg in the water were separated by continuous-flow centrifugation in the field. The Hg and other pollutants such as wood chips and salt had been discharged from a chlor-alkali plant and paper mill at Dryden, Ontario. Concentrations and loadings of particulate methyl mercury (CH3Hg+) and total particulate Hg (and loadings of total ‘dissolved’ Hg) were greatest during the spring flood (April-May) owing to accelerated resuspension and transport of sediments. Concentrations of ‘dissolved’ CH3Hg+, however, were highest in the summer (July–September), probably reflecting stimulation of microbial methylating activity by elevated temperatures, together with factors such as reduced levels of metal-scavenging particulates and minimal dilution by runoff. Total dissolved Hg concentrations were relatively high in September at polluted sites only, possibly because of desorption from sediments due to elevated concentrations of Cl− ions. Loadings of dissolved CH3Hg+ tended to be high in the summer but were generally depressed (suggesting sorption by suspended particles) during the major spring-flood episode in May. During July–August dissolved CH3Hg+ was a function of total dissolved Hg, suggesting rapid biomethylation of desorbed inorganic Hg; but in general dissolved and suspended CH3Hg+ levels depended on environmental variables and were unrelated to total Hg concentrations. In the summer only, total dissolved Hg was a function of dissolved Cl−. Hg species in particulates were associated with sulfides, hydrated Fe and Mn oxides, organic matter (notably high molecular weight humic and humic-Fe components), and selenium (Se); but CH3Hg+ and total Hg differed in their specific preferences for binding agents, implying that binding sites discriminate between CH3Hg+ and Hg2+ ions. CH3Hg+ was associated with sulfide and (in the spring only) with Fe oxides, whereas total Hg was associated with organic matter and Se and with DTPA- and NaOH-extractable Fe in the spring but with Mn oxide and NaOH-extractable organics in the summer. Sulfides were most abundant in May, indicating that they were eroded from bottom sediments, but Fe and Mn oxides were most abundant in the summer, probably owing to activities of filamentous iron bacteria and other micro-organisms. Particulate Hg was 98–100% nonextractable by mild solvents such as Ca acetate, CaCl2, dilute acetic acid, and (at polluted sites only) DTPA solutions, suggesting that the particulate Hg mobilized in the spring may not be readily available to organisms; association with Se and high molecular weight humic matter also supports this hypothesis. Hg probably becomes more bio-available in the summer, as suggested by the upsurge in dissolved CH3Hg+ and total dissolved Hg levels, and by increases in the solubility of particulate Hg in acetic acid, DTPA, H2O2, and NaOH solutions, as well as an increase in the relative importance of lower molecular weight fractions of NaOH-extractable Hg (in September). Regional variations in Hg speciation and partitioning reflected a gradient in sediment composition from wood chips near Dryden to silt-clay mud further downstream. Hg in silt-clay mud relatively far (〉 35 km) downstream from the source of pollution or in unpolluted areas appeared to be more readily solubilized by Cl− ions or chelators such as DTPA, more readily methylated (as indicated by downstream increases in dissolved CH3Hg+ levels and CH3Hg+/total Hg ratios), and was to a greater degree organically bound (H2O2-extractable), and thus was probably more bio-available, than Hg in wood-chip deposits. Possible explanations include weaker binding of Hg by the mud, the more finely divided state of the mud, and improved microbial growth at lower concentrations of toxic pollutants. Owing to enrichment in sulfides and Fe oxides, resuspended wood-chip sediments were especially efficient scavengers of CH3Hg+. The results indicate that in any pollution abatement plan aimed at lowering the Hg levels in the biota of lakes fed by the Wabigoon River, immobilization, removal, or detoxification of dissolved as well as particulate forms of Hg in the river would probably have to be considered. Possibly, Hg species could be ‘scrubbed’ from the river water by increasing the suspended load and by sedimentation and treatment with Hg-binding agents in special receiving basins.

Notes: Abstract Sex attractants known for 145 species of noctuid moths have many common features both as to chemical constituents and to their relationships in blends. The great majority of constituents are straight-chain (Z)-alkenols, -alkenals, or -alkenyl acetates of even carbon number (10 through 16). The unsaturation is nonterminal in odd-numbered positions (5 through 11). In effective lures, these components are blended in specific ratios and the components in a sex pheromone or sex attractant blend are structurally related by “one-change” steps. This means that any blend component differs from one or more other components by a single structural alteration, such as a change in double bond position, or a change in carbon chain length, or a change in the oxygen function. For the few multicomponent systems known in detail, the central place in the “one-change” framework is occupied by the predominant blend component. Different patterns of occurrence of lure components occur in the subfamilies Acronictinae, Noctuinae, Hadeninae, Cuculliinae, Amphipyrinae, Heliothidinae, Plusiinae, Acontiinae, and Pantheinae, and some subfamilies are as yet without known lures. Some guiding principles for elucidation of blend compositions for unstudied species are presented; these guidelines can also be used in improvement of some synthetic blends of unsatisfactory quality.

Notes: Abstract Human activities generate many pollutants from different land uses. These pollutants include nutrients (e.g., phosphorus and nitrogen), toxic substances (e.g., heavy metals and pesticides), and other substances (e.g., chlorides and salts). These materials often enter a river at some upstream point and are transported downstream by the flowing water. Many substances are transported both during storms and during normal river flow and often the major portion of the transport occurs during the storms. This paper considers the quantification of transport primarily during storms. First, the characteristics of storm transport are discussed. Then, a calculation method for estimating the distance of travel for sediment related materials is presented. Third, a technique to estimate the amount of a given chemical passing a point in a stream over a specified period of time is presented. The last part of this paper contains a technique for tracing the movement of substances through a river network. In particular, this procedure yields information as to the source of given pollutants over the entire Storm period.

Notes: Abstract To understand the nature of sediment-associated nutrient and contaminant transport dynamics in fluvial systems, a stormflow sampling program of suspended solids is reported for one water year in a representative rural diffuse source catchment of southeastern Ontario. Bulk samples of subsieve suspended solids were obtained using field-portable continuous-flow centrifuge apparatus. The physical and geochemical properties of suspended solids show no significant intersite differences over reaches of 1 500–2 000 m, yet display distinctive seasonal trends. Systematic seasonal changes in particle size, organic content, and Ca, P, Mn, Al, Ti, Fe, and K appear to reflect the changing role of partial area hydrology. Ca, P, and Mn are bioaccumulated by stream algae. Mineral signature is relatively constant over the year.

Notes: Abstract The 40,000-dalton glycoprotein and 2000-dalton peptide inducing selective Ca2+-transport through bilayer lipid membranes were isolated from beef heart homogenate and mitochondria. Micromolar concentrations of these substances were found to increase the conductivity of membranes by 3–4 orders. Transmembrane Ca2+ gradient induces an electric potential difference whose magnitude is close to the theoretical for ideal Ca2+ selectivity. The inhibitor of mitochondrial Ca2+ transport, ruthenium red, abolishes both the glycoprotein-and peptide-induced Ca2+ transport in bilayer lipid membranes. Thiol groups essential for Ca2+ transport activity were revealed in the glycoprotein and peptide. Addition of these substances to rat liver mitochondria induces Ca2+-dependent inhibition of the state 3 respiration that can be released by uncouplers (oligomycin-like effect).

Notes: Abstract A new site of secretion of a chemical trail marker was found on the sternum at the tip of the last abdominal segment of the larva of the eastern tent caterpillarMalacosoma americanum. Larvae marked from this site by drawing their sterna along the substrate when they extended existing trails in search of food and again when they established recruitment trails to food-finds. Differences in the quantity or quality of the marker deposited by exploring and recruiting caterpillars may account for the greater activity of the recruitment trails.

Notes: Abstract 90% (Z)-11-tetradecen-1-yl acetate, 5% (Z)-9-tetradecen-1-yl acetate, 5% (Z)-11-tetradecen-1-ol, dodecyl acetate (〈1%), and tetradecyl acetate (〈1%) were identified from gland extracts ofPandemis heparana females by gas chromatography and gas chromatography-mass spectrometry analysis (including mass fragmentography studies), chemical characterization, total synthesis, laboratory and field bioassays. In the field, a mixture of (Z)-11-tetradecen-l-yl acetate and (Z)-9-tetradecen-l-yl acetate (95∶5) was found to be essential for attractiveness ofP. heparana males.