Vermicompost extracts influence growth,mineral nutrients,phytonutrients and antioxidant activity in pak choi (Brassica rapa cv. Bonsai,Chinensis group) grown under vermicompost and chemical fertiliser

BACKGROUND: Multiple studies have been reported on the effect of compost tea on suppression of certain plant diseases. However, relatively little work has been done to investigate the effect of vermicompost tea on yield and nutritional quality of vegetable crops. In this study, experiments were conducted to determine the effect of extraction method on vermicompost tea quality and subsequent effects on growth, mineral nutrients, phytonutrients and antioxidant activity of pak choi plants grown under organic (vermicompost) and synthetic (Osmocote) fertilisation. Three vermicompost teas obtained by different extraction methods, namely non‐aerated vermicompost tea (NCT), aerated vermicompost tea (ACT) and aerated vermicompost tea augmented with microbial enhancer (ACTME), were applied to the plants. Aerated water served as control. RESULTS: Mineral nutrients were significantly higher in ACTME compared with other teas, but total microbial population and activity did not differ with extraction method. All vermicompost teas similarly enhanced plant production, mineral nutrients and total carotenoids, and this effect was most prominent under organic fertilisation. Antioxidant activity and total phenolics were higher under organic compared with synthetic fertilisation. Vermicompost teas generally decreased phenolics under organic fertilisation and increased them under synthetic fertilisation compared with the control. CONCLUSION: The effect of vermicompost tea on crop growth is largely attributable to mineral nutrient, particularly N, uptake by plants. Non‐significant differences among extraction methods on plant response within fertiliser regimes suggest that aeration and additives are not necessary for growth promotion and nutrient quality under the conditions reported here. Copyright © 2009 Society of Chemical Industry     

Modeling secondary organic aerosol formation via multiphase partitioning with molecular data

A new model for atmospheric secondary organic aerosol (SOA) is presented for biogenic compounds. It is based to the extent possible on experimental molecular SOA data, and it is compatible with any existing gas-phase chemical kinetic mechanism. Six SOA precursors or groups of precursors are used to represent biogenic monoterpenes and sesquiterpenes. SOA formation is modeled using five SOA surrogates to represent classes of compounds with different partitioning properties, e.g., hydrophobicity, aqueous solubility, acid dissociation, and saturation vapor pressure. Model simulations are evaluated against smog chamber data for SOA yields and some adjustments are made to uncertain stoichiometric coefficients and saturation vapor pressure parameters to improve model performance. The model is applied undertypical atmospheric conditions to exemplify the effect of relative humidity on SOA formation and the relative contributions of hydrophilic and hydrophobic SOA.     

Fast-scan deposition-stripping voltammetry at carbon-fiber microelectrodes: real-time, subsecond, mercury free measurements of copper

Elevated concentrations of hazardous metals in aquatic systems are known to threaten human health. Mobility, bioavailability, and toxicity of metals are controlled by chemical speciation, a dynamic process. Understanding metal behavior is limited by the lack of analytical methods that can provide rapid, sensitive, in situ measurements. While electrochemistry shows promise, it is limited by its temporal resolution and the necessity for Hg modified electrodes. In this letter, we apply fast-scan deposition-stripping voltammetry at carbon-fiber microelectrodes for in situ measurements of Cu(II). We present a novel, Hg-free technique that can measure Cu(II) with ppb sensitivity at 100 ms temporal resolution.     

Self-assembly of organic acid molecules on the metal oxide surface of a cupronickel alloy

Corrosion of the metal oxide surface of cupronickel (CuNi) alloys is a problem in applications such as household water pipes, industrial pipelines, and marine vessels. On other substrates, thin films have been used as barriers to corrosion. Here, the formation of self-assembled monolayers (SAMs) on the CuNi metal oxide surface has been investigated. Stable, well-ordered SAMs of octadecylphosphonic acid (ODPA) and 16-phosphonohexadecanoic acid (COOH-PA) were formed on the metal oxide surface of CuNi foils (55% Cu/45% Ni) using a solution deposition method. The ODPA modified surfaces could be used to provide a non-reactive barrier that inhibits corrosion of the CuNi metal oxide surface. Meanwhile, COOH-PA films could be used for further surface reactions such as surface initiated polymerization, in which polymer coatings are grown directly from a well-ordered film. Film-modified surfaces were characterized using diffuse reflectance infrared Fourier transform spectroscopy, contact angle analysis, and matrix assisted laser desorption ionization time of flight mass spectrometry. The ability of the films to inhibit corrosion by limiting oxidation of the CuNi surface was assessed using cyclic voltammetry.     

Low threshold room-temperature lasing of CdS nanowires

The synthesis of CdS nanostructures (bands, wires, irregular structures) was investigated by systematic variation of temperature and gas pressure, to deduce a comprehensive growth phase diagram. The high quality nanowires were further investigated and show stoichiometric composition of CdS as well as a single-crystalline lattice without any evidence of extended defects. The luminescence of individual nanowires at low excitation shows a strong near band edge emission at 2.41?eV indicating a low point defect concentration. Sharp peaks evolve at higher laser power and finally dominate the luminescence spectrum. The power dependence of the spectrum clearly shows all the characteristics of amplified stimulated emission and lasing action in the nanowire cavity. A low threshold was determined as 10?kW?cm(-2) for lasing at room temperature with a slope efficiency of 5-10% and a Q factor of up to 1200. The length and diameter relations necessary for lasing of individual nanowires was investigated.     

Training and dissemination of cognitive behavior therapy for depression in adults: A preliminary examination of therapist competence and client outcomes.

Objective: In this study, the authors examined the feasibility and effectiveness of training community therapists to deliver cognitive behavior therapy (CBT) for depression. Method: Participants were therapists (n = 12) and clients (n = 116; mean age = 41 years, 63% women) presenting for treatment of depression at a not-for-profit and designated community mental health center for St. Joseph County, Indiana. The training model included a 2-day workshop followed by 1 year of phone consultations. CBT competence ratings from the Cognitive Therapy Scale were obtained prior to training and at 6 and 12 months posttraining. Two different groups of clients, a treatment-as-usual (TAU) group (n = 74) and a CBT group (n = 42), were compared with respect to decrease in symptoms of depression (assessed with the Beck Depression Inventory) and anxiety (assessed with the Beck Anxiety Inventory). Results: Therapists showed significant increases in total scores from pretraining to 6 months posttraining, increases that were maintained at 12 months. The increase in the total score reflected gains on items that specifically measure CBT skills and structure. Although both TAU and CBT resulted in a significant decrease in depressive symptoms, the CBT clients showed significantly greater change than the TAU clients, F(2, 113) = 53.40, p     

Effect of electron beam irradiation on quality indicators of peanut butter over a storage period

Electron beam (e-beam) irradiation is an effective non-thermal processing step for the reduction of Salmonella in peanut butter. The objective of this study was to evaluate the effects of e-beam irradiation on quality indicators of peanut butter. Peanut butter samples were exposed to a range of e-beam doses and examined over a 14-day period at 22 °C. Colour analysis (L^∗, a^∗, b^∗), spreadability, peroxide values (PV) and thiobarbituric acid reactive substances test (TBARS) for lipid oxidation were monitored, fatty acid and amino acid profiles were verified and protein degradation was determined by sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE). Changes in colour, PV, and TBARS were observed as e-beam dose increased. No significant changes in spreadability were observed (P > 0.05). When applied to peanut butter, e-beam irradiation will produce significant changes in quality indicators; future studies should include sensory evaluation and consumer acceptance studies.     

Eukaryotic assimilatory nitrate reductase fractionates N and O isotopes with a ratio near unity

In order to (i) establish the biological systematics necessary to interpret nitrogen (N) and oxygen (O) isotope ratios of nitrate ((15)N/(14)N and (18)O/(16)O) in the environment and (ii) investigate the potential for isotopes to elucidate the mechanism of a key N cycle enzyme, we measured the nitrate N and O isotope effects ((15)ε and (18)ε) for nitrate reduction by two assimilatory eukaryotic nitrate reductase (eukNR) enzymes. The (15)ε for purified extracts of NADPH eukNR from the fungus Aspergillus niger and the (15)ε for NADH eukNR from cell homogenates of the marine diatom Thalassiosira weissflogii were indistinguishable, yielding a mean (15)ε for the enzyme of 26.6 ± 0.2‰. Both forms of eukNR imparted near equivalent fractionation on N and O isotopes. The increase in (18)O/(16)O versus the increase in (15)N/(14)N (relative to their natural abundances) was 0.96 ± 0.01 for NADPH eukNR and 1.09 ± 0.03 for NADH eukNR. These results are the first reliable measurements of the coupled N and O isotope effects for any form of eukNR. They support the prevailing view that intracellular reduction by eukNR is the dominant step in isotope fractionation during nitrate assimilation and that it drives the (18)ε:(15)ε ≈ 1 observed in phytoplankton cultures, suggesting that this O-to-N isotope signature will apply broadly in the environment. Our measured (15)ε and (18)ε may represent the intrinsic isotope effects for eukNR-mediated N-O bond rupture, a potential constraint on the nature of the enzyme's transition state.     

Bayesian analysis of a reduced-form air quality model

Numerical air quality models are being used for assessing emission control strategies for improving ambient pollution levels across the globe. This paper applies probabilistic modeling to evaluate the effectiveness of emission reduction scenarios aimed at lowering ground-level ozone concentrations. A Bayesian hierarchical model is used to combine air quality model output and monitoring data in order to characterize the impact of emissions reductions while accounting for different degrees of uncertainty in the modeled emissions inputs. The probabilistic model predictions are weighted based on population density in order to better quantify the societal benefits/disbenefits of four hypothetical emission reduction scenarios in which domain-wide NO(x) emissions from various sectors are reduced individually and then simultaneously. Cross validation analysis shows the statistical model performs well compared to observed ozone levels. Accounting for the variability and uncertainty in the emissions and atmospheric systems being modeled is shown to impact how emission reduction scenarios would be ranked, compared to standard methodology.