Leaching of pesticides in tea brew.

A cup of tea that cheers can also be an important route of human exposure to pesticide residues. It is important to evaluate the percent transfer of pesticide residue from dried (made) tea to tea infusion, as tea is subjected to an infusion process prior to human consumption. To investigate the pesticide translocation, 13 pesticides commonly used on tea were studied by subjection of fortified teas to infusion. Analytes of interest were quantified by gas-liquid chromatography with nitrogen-phosphorus and electron capture detectors. Interestingly, water solubility of pesticides did not necessarily indicate a shift of residues toward their preferential accumulation in infusion. The pesticides with larger partition coefficient (K(ow)) values remained nonextractable in infusing water. Further, boiling for longer periods (extended brewing time) resulted in higher transfer of pesticides to tea brew.     

Impacts of elemental S applied under various temperature and moisture regimes on pH and available P in acidic, neutral and alkaline soils

We evaluated the effect of elemental S (S⁰) under three moisture (40, 60, 120% water-filled pore space; WFPS) and three temperature regimes (12, 24, 36°C) on changes in pH and available P (0.5 N NaHCO₃-extractable P) concentrations in acidic (pH 4.9), neutral (pH 7.1) and alkaline (pH 10.2) soils. Repacked soil cores were incubated for 0, 14, 28 and 42 days. Application of S⁰ did not alter the trends of pH in acidic and neutral soils at all moisture regimes but promoted a decrease in the pH of alkaline soil under aerobic conditions (40%, 60% WFPS). Moisture and temperature had profound effects on the available P concentrations in all three soils, accumulation of available P being greatest under flooded conditions (120% WFPS) at 36°C. Application of S⁰ in acidic, neutral and alkaline soils resulted in the net accumulation of 16.5, 14.5 and 13 g P g^–1 soil after 42 days at 60% WFPS, but had no effect under flooded conditions. The greatest available P accumulations in the respective soils were 19, 19.5 and 20 g P g^–1 soil (equivalent to 38, 41, 45 kg P ha^–1) with the combined effects of 36°C, 60% WFPS and applied S⁰. The results of our study revealed that oxidation of S⁰ lowered the pH of alkaline soil (r=–0.88, P<0.01), which in turn enhanced available P concentrations. Also, considering the significant relationship between the release of sulphate and accumulation of P, even in acidic soil (r=0.92, P<0.01) and neutral soil (r=0.85, P<0.01) where the decrease in pH was smaller, it is possible that the stimulatory effect of sulphate on the availability of P was due to its concurrent desorption from the colloidal surface, release from fixation sites and/or mineralization of organic P. Thus, in the humid tropics and irrigated subtropics where high moisture and temperature regimes are prevalent, the application of S⁰ could be beneficial not only in alleviating S deficiency in soils but also for enhancing the availability of P in arable soils, irrespective of their initial pH.     

Investigation of the effect of Equivac® HeV Hendra virus vaccination on Thoroughbred racing performance

Objective

To evaluate the effect of Equivac® HeV Hendra virus vaccine on Thoroughbred racing performance.

Design

Retrospective pre‐post intervention study.

Methods

Thoroughbreds with at least one start at one of six major south‐eastern Queensland race tracks between 1 July 2012 and 31 December 2016 and with starts in the 3‐month periods before and after Hendra virus vaccinations were identified. Piecewise linear mixed models compared the trends in ‘Timeform rating’ and ‘margin to winner’ before and after initial Hendra virus vaccination. Generalised linear mixed models similarly compared the odds of ‘winning’, ‘placing’ (1st–3rd) and ‘winning any prize money’. Timeform rating trends were also compared before and after the second and subsequent vaccinations.

Results

Analysis of data from 4208 race starts by 755 horses revealed no significant difference in performance in the 3 months before versus 3 months after initial Hendra vaccination for Timeform rating (P = 0.32), ‘Margin to winner’ (P = 0.45), prize money won (P = 0.25), wins (P = 0.64) or placings (P = 0.77). Further analysis for Timeform rating for 7844 race starts by 928 horses failed to identify any significant change in Timeform rating trends before versus after the second and subsequent vaccinations (P = 0.16) or any evidence of a cumulative effect for the number of vaccines received (P = 0.22).

Conclusion

No evidence of an effect of Hendra virus vaccination on racing performance was found. The findings allow owners, trainers, industry regulators and animal health authorities to make informed decisions about vaccination.     

Mineralization-immobilization of soil organic S and oxidation of elemental S in subtropical soils under flooded and nonflooded conditions

Information on the influence of soil moisture on elemental sulphur (S⁰) oxidation and transformation into organic S in semi-arid subtropical soils is scarce. We studied the impact of three moisture regimes on the mineralization of soil organic S, and the oxidation and immobilization of S⁰ in acidic (pH 4.9), neutral (pH 7.1) and alkaline (pH 10.2) subtropical soils. Repacked soil cores were incubated under aerobic (40% and 60% water-filled pore space, WFPS) and flooded soil conditions (120% WFPS) for 0, 14, 28 and 42 days with and without incorporated S⁰ (500 µg g^-1 soil). Soil moisture had profound effects on these processes and the mineralization of native soil organic S, oxidation of applied S⁰ and transformation of S⁰ into soil organic S proceeded most rapidly at 60% WFPS, irrespective of soil pH. Mineralization of native soil organic S resulted in the accumulation of 34, 49 and 44 g SO₄^2--S g^-1 soil in acidic, neutral and alkaline soil in a 42-day period at 60% WFPS. The oxidation rate of added S⁰ during the initial 14-day period at 60% WFPS was highest in alkaline soil (428 µg S cm^-2 day^-1), followed by neutral soil (326 µg S cm^-2 day^-1), and lowest in acidic soil (235 µg S cm^-2 day^-1). These rates are several folds higher than those reported in earlier studies because now we computed the oxidation rates by including the amount of S⁰ that was immobilized to organic S. Of the applied S⁰ at 40% and 60% WFPS, 2.6% and 6.0%, 3.4% and 10.0%, and 9.4% and 14.4% oxidized to SO₄^2-, and 15.0% and 17.6%, 17.6% and 19.6%, and 17.6% and 23.6% transformed into organic S in the 42-day period in acidic, neutral and alkaline soil, respectively. These results suggest that in order to synchronize the availability of S with plant need, S⁰ may be applied well before the seeding of crops especially in acidic soils and in rainfed regions where soil moisture remains at less than 60% WFPS. Apparently no oxidation of S⁰ and significant reduction of SO₄^2--S (7, 53 and 78 µg SO₄^2--S g^-1 in acidic, neutral and alkaline soil, respectively) under flooded conditions suggest that S⁰ is least effective for correcting S deficiency in flooded soil systems such as rice fields.     

Bulk Superconductivity at 122 K in T1(Ba,Ca)2Ca3Cu4O10.5+8 with Four Consecutive Copper Layers

The observed increase of superconducting transition temperature (T(c)) with the number of copper oxide planes continues in the four-[CuO(2)](-2) layer (single TI layer) oxide superconductor, which has been prepared with > 80% purity and was magnetically aligned for crystallographic identification. A master scaling curve is proposed, which ties together the T(c)'s of virtually all known Bi and Tl oxide superconductors, and shows that the Tl(Bi) layers play an essential role in the superconductivity. publication 350 of the Barnett Institute.