Ice sheet and solid Earth influences on far-field sea-level histories

Previous predictions of sea-level change subsequent to the last glacial maximum show significant, systematic discrepancies between observations at Tahiti, Huon Peninsula, and Sunda Shelf during Lateglacial time (approximately 14,000 to 9000 calibrated years before the present). We demonstrate that a model of glacial isostatic adjustment characterized by both a high-viscosity lower mantle (4 x 10(22) Pa s) and a large contribution from the Antarctic ice sheet to meltwater pulse IA (approximately 15-meters eustatic equivalent) resolves these discrepancies. This result supports arguments that an early and rapid Antarctic deglaciation contributed to a sequence of climatic events that ended the most recent glacial period of the current ice age.     

Insecticidal potency of novel compounds on multiple insect species of medical and veterinary importance

BACKGROUND: Vector‐borne diseases continue to present significant threats to human, animal and plant health. Mosquitoes, houseflies, sand flies and stable flies are well‐known vectors of several human and animal pathogens. The toxicity of selected semiochemicals with molecular structures indicative of insecticidal activity was determined against these insect species with the aim of developing novel insecticides toxic to multiple insect species. RESULTS: Three semiochemicals, namely beta‐damascone, cyclemone A and melafleur, showed remarkable toxicity to three mosquitoes, Aedes aegypti L., Ae. albopictus (Skuse) and Anopheles quadrimaculatus Say, the housefly, Musca domestica L., the stable fly, Stomoxys calcitrans L., and the sand fly, Lutzomyia shannoni (Dyar). The chemicals were equally toxic to several field‐collected permethrin‐tolerant housefly strains. When formulated as 500 mL L^?1 emulsifiable concentrates, the chemicals demonstrated stability and toxicity on filter paper and camouflage military fabrics, with persistence up to 8 days under laboratory conditions. The chemicals were equally effective under field conditions when evaluated on unpainted plywood panels, although a higher dosage was required under field conditions to achieve similar efficacy. CONCLUSION: Laboratory quantification of LC₅₀ values and field efficacy of three semiochemicals as formulated compounds on mosquitoes, houseflies, stable flies and sand flies showed that these semiochemicals could serve as potent insecticides for multiple insect species. Copyright © 2010 Society of Chemical Industry     

Emissions of CO2, N2O,and NO in conventional and no-till management practices in Rondônia,Brazil

Efforts to restore productivity of pastures often employ agricultural management regimes involving either tillage or no-tillage options combined with various combinations of fertilizer application, herbicide use and the planting of a cash crop prior to the planting of forage grasses. Here we report on the emissions of CO₂, N₂O and NO from the initial phases (first 6 months) of three treatments in central Rondônia. The treatments were (1) control; (2) conventional tillage followed by planting of forage grass (Brachiaria brizantha) and fertilizer additions; (3) no-tillage/herbicide treatment followed by two plantings, the first being a cash crop of rice followed by forage grass. In treatment 3, the rice was fertilized. Relative to the control, tillage increased CO₂ emission by 37% over the first 2 months, while the no-tillage/herbicide regime decreased CO₂ emissions by 7% over the same period. The cumulative N₂O emissions over the first 2 months from the tillage regime (0.94 kg N ha^–1) were much higher than the N₂O releases from either the no-tillage/herbicide regime (0.64 kg N ha^–1) or the control treatment (0.04 kg N ha^–1). The highest levels of N₂O fluxes from both management regimes were observed following N fertilizations. The cumulative NO releases over the first 2 months were largest in the tillage treatment (0.98 kg N ha^–1), intermediate in the no-tillage treatment (0.72 kg N ha^–1), and smallest in the control treatment (0.12 kg N ha^–1). For the first week following fertilization the percentage of fertilizer N lost as N₂O plus NO was 1.0% for the tillage treatment and 3.0% for the no-tillage treatment.     

The antiproliferative and differentiating effects of human leukemic U937 cells are mediated by cytokines from activated mononuclear cells by dietary mushrooms

Proliferation of human leukemic U937 cells was remarkably inhibited by conditioned medium (CM) of human peripheral blood mononuclear cells (MNC-CM) stimulated with cold-water extracts (CWE) (10-800 microg/mL of medium) of dietary mushrooms, Hypsizigus mamoreus (HM), Agrocybe aegerita (AA), Flammulina velutipes (FV), whereas insignificant results were observed when cells were cultured in the presence of CWE at the corresponding level. Water extracts from mushrooms were fractionated by Sephadex G-50 chromatography, and the pooled high molecular weight fraction (F1) (200 microg/mL) of HM (HM1) and AA (AA1) exhibited growth inhibitions >80% on U937 cells. Interestingly, the thus-cultured U937 cells showed high nitroblue tetrazolium (NBT) positive (>68%) and nonspecific esterase (NSE) positive (>47%) percentages, revealing the remarkable differentiation into monocytes/macrophages upon incubation with HM1- and AA1-stimulated MNC-CM. In addition, assays for the expressions of monocyte-associated antigens, CD11b, CD14, and CD68, also evidenced the remarkable differentiation of U937 cells into monocytes/macrophages by presenting high CD maker positive percentages (>50%). Tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta in CM of HM1-stimulated MNC for 1 day (MNC-CM-1) were 1350 and 1374 pg/mL, respectively, revealing the potent antitumor and differentiation-inducing activities of HM. Of note, MNC-CM-1 appeared to be more effective than day 5 MNC-CM (MNC-CM-5) in both antitumor and differentiation-inducing activities.