Effects of rice husk biochar and sugar-mill by-products on methane consumption from two different soils

Methane (CH4) is an important greenhouse gas with a global warming potential (GWP) 25 times greater than carbon dioxide (CO2) that can be produced or consumed in soils depending on environmental conditions and other factors. Biochar application to soils has been shown to reduce CH4 emissions and to increase CH4 consumption. However, the effects of rice husk biochar (RB) have not been thoroughly investigated. Two 60-day laboratory incubation experiments were conducted to investigate the effects of amending two soil types with RB, raw mill mud (MM) and composted mill mud (CM) on soil CH4 consumption and emissions. Soil cores incubated in 1 L glass jars and gas samples were analysed for CH4 using gas chromatography. Average CH4 consumption rates varied from -0.06 to -0.68 g CH4-C( )/ha/d in sandy loam soil and -0.59 to -1.00 g CH4-C/ha/d in clay soil. Application of RB resulted in CH4 uptake of -0.52 to -0.55 g CH4-C/ha/d in sandy loam and -0.76 to -0.91 g CH4-C/ha/d in clay soil. Addition of MM showed low CH4 emissions or consumption at 60% water-filled pore space (WFPS) in both soils. However, at high water contents (>75% WFPS) the application of MM produced high rates of CH4 emissions which were significantly suppressed when RB was added. Cumulative emissions of the MM treatment produced 108.9 g CH4-C/ha at 75% WFPS and 11 459.3 g CH4-C/ha at 90% WFPS in sandy loam soil over a period of 60 days. RB can increase CH4 uptake under low soil water content (SWC) and decrease CH4 emissions under anaerobic conditions. CM expressed more potential to reduce CH4 emissions than those of MM.

Plasma metabolomics reveals biomarkers of the atherosclerosis

Atherosclerotic cardiovascular disease remains the leading cause of morbidity and mortality in industrialized societies. The lack of metabolite biomarkers has impeded the clinical diagnosis of atherosclerosis so far. In this study, stable atherosclerosis patients (n=16) and age- and sex-matched non-atherosclerosis healthy subjects (n=28) were recruited from the local community (Harbin, P. R. China). The plasma was collected from each study subject and was subjected to metabolomics analysis by GC/MS. Pattern recognition analyses (principal components analysis, orthogonal partial least-squares discriminate analysis, and hierarchical clustering analysis) commonly demonstrated plasma metabolome, which was significantly different from atherosclerotic and non-atherosclerotic subjects. The development of atherosclerosis-induced metabolic perturbations of fatty acids, such as palmitate, stearate, and 1-monolinoleoylglycerol, was confirmed consistent with previous publication, showing that palmitate significantly contributes to atherosclerosis development via targeting apoptosis and inflammation pathways. Altogether, this study demonstrated that the development of atherosclerosis directly perturbed fatty acid metabolism, especially that of palmitate, which was confirmed as a phenotypic biomarker for clinical diagnosis of atherosclerosis.

Desorption electrospray ionisation mass spectrometry reveals in situ modification of a hindered amine light stabiliser resulting from direct N–OR bond cleavage

Detection and characterisation of structural modifications of a hindered amine light stabiliser (HALS) directly from a polyester-based coil coating have been achieved by desorption electrospray ionisation mass spectrometry (DESI-MS) for the first time. In situ detection is made possible by exposing the coating to an acetone vapour atmosphere prior to analysis. This is a gentle and non-destructive treatment that allows diffusion of analyte to the surface without promoting lateral migration. Using this approach a major structural modification of the HALS TINUVIN®123 (bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate) was discovered where one N-ether piperidine moiety (N-OC8H17) is converted to a secondary piperidine (N–H). With the use of 2-dimensional DESI-MS imaging the modification was observed to arise during high curing temperatures (ca. 260 °C) and under simulated physiological conditions (80 °C, full solar spectrum). It is proposed that the secondary piperidine derivative is a result of a highly reactive aminyl radical intermediate produced by N–O homolytic bond cleavage. The nature of the bond cleavage is also suggested by ESR spin-trapping experiments employing α-phenyl-N-tert-butyl nitrone (PBN) in toluene at 80 °C. The presence of a secondary piperidine derivative in situ and the implication of N–OR competing with NO–R bond cleavage suggest an alternative pathway for generation of the nitroxyl radical—an essential requirement in anti-oxidant activity that has not previously been described for the N-ether sub-class of HALS.

Novel use of faecal sterols to assess human faecal contamination in Antarctica : a likelihood assessment matrix for environmental monitoring

Wastewater containing human sewage is often discharged with little or no treatment into the Antarctic marine environment. Faecal sterols (primarily coprostanol) in sediments have been used for assessment of human sewage contamination in this environment, but in situ production and indigenous faunal inputs can confound such determinations. Using gas chromatography with mass spectral detection profiles of both C27 and C29 sterols, potential sources of faecal sterols were examined in nearshore marine sediments, encompassing sites proximal and distal to the wastewater outfall at Davis Station. Faeces from indigenous seals and penguins were also examined. Faeces from several indigenous species contained significant quantities of coprostanol but not 24-ethylcoprostanol, which is present in human faeces. In situ coprostanol and 24-ethylcoprostanol production was identified by co-production of their respective epi isomers at sites remote from the wastewat er source and in high total organic matter sediments. A C 29 sterols-based polyphasic likelihood assessment matrix for human sewage contamination is presented, which distinguishes human from local fauna faecal inputs and in situ production in the Antarctic environment. Sewage contamination was detected up to 1.5 km from Davis Station.

Metabolic and hormonal responses to isoenergetic high-intensity interval exercise and continuous moderate-intensity exercise

This study investigated the effects of high-intensity interval training (HIIT) vs. work-matched moderate-intensity continuous exercise (MOD) on metabolism and counterregulatory stress hormones. In a randomized and counterbalanced order, 10 well-trained male cyclists and triathletes completed a HIIT session [81.6 ± 3.7% maximum oxygen consumption (V̇o2 max); 72.0 ± 3.2% peak power output; 792 ± 95 kJ] and a MOD session (66.7 ± 3.5% V̇o2 max; 48.5 ± 3.1% peak power output; 797 ± 95 kJ). Blood samples were collected before, immediately after, and 1 and 2 h postexercise. Carbohydrate oxidation was higher (P = 0.037; 20%), whereas fat oxidation was lower (P = 0.037; −47%) during HIIT vs. MOD. Immediately after exercise, plasma glucose (P = 0.024; 20%) and lactate (P < 0.01; 5.4×) were higher in HIIT vs. MOD, whereas total serum free fatty acid concentration was not significantly different (P = 0.33). Targeted gas chromatography-mass spectromtery metabolomics analysis identified and quantified 49 metabolites in plasma, among which 11 changed after both HIIT and MOD, 13 changed only after HIIT, and 5 changed only after MOD. Notable changes included substantial increases in tricarboxylic acid intermediates and monounsaturated fatty acids after HIIT and marked decreases in amino acids during recovery from both trials. Plasma adrenocorticotrophic hormone (P = 0.019), cortisol (P < 0.01), and growth hormone (P < 0.01) were all higher immediately after HIIT. Plasma norepinephrine (P = 0.11) and interleukin-6 (P = 0.20) immediately after exercise were not significantly different between trials. Plasma insulin decreased during recovery from both HIIT and MOD (P < 0.01). These data indicate distinct differences in specific metabolites and counterregulatory hormones following HIIT vs. MOD and highlight the value of targeted metabolomic analysis to provide more detailed insights into the metabolic demands of exercise.

Effects of mesostructured silica catalysts on the depolymerization of organosolv lignin fractionated from woody eucalyptus

Isolated and purified organosolv eucalyptus wood lignin was depolymerized at different temperatures with and without mesostructured silica catalysts (i.e., SBA-15, MCM-41, ZrO2-SBA-15 and ZrO2-MCM-41). It was found that at 300 oC for 1 h with a solid/liquid ratio of 0.0175/1 (w/v), the SBA-15 catalyst with high acidity gave the highest syringol yield of 23.0% in a methanol/water mixture (50/50, wt/wt). Doping with ZrO2 over these catalysts did not increase syringol yield, but increased the total amount of solid residue. Gas chromatography-mass spectrometry (GC-MS) also identified other main phenolic compounds such as 1-(4-hydroxy-3,5-dimethoxyphenyl)-ethanone, 1,2-benzenediol, and 4-hydroxy-3,5-dimethoxy-benzaldehyde. Analysis of the lignin residues with Fourier transform-Infrared spectroscopy (FT-IR) indicated decreases in the absorption bands intensities of OH group, C-O stretching of syringyl ring and aromatic C-H deformation of syringol unit, and an increase in band intensities associated with the guaiacyl ring, confirming the type of products formed.

Polybrominated diphenyl ether (PBDE) human half lives estimated from North Americans moving to Australia

Human half-lives of PentaBDE congeners have been estimated from the decline in serum concentrations measured over a 6-12 month period for a population of exchange students moving from North America to Australia. Australian serum PBDE concentrations are typically between 5 -10 times lower than in North America and we can therefore hypothesize that if the biological half-life is sufficiently short we would observe a decline in serum concentration with length of residence in Australia. Thirty students were recruited over a period of 3 years from whom serum were archived every 2 months during their stay in Australia. Australian residents (n=22) were also sampled longitudinally to estimate general population background levels. All serum samples were analyzed by gas chromatography high resolution mass spectrometry. Key findings confirmed that BDE-47 concentrations in the Australians (median 2.3;

Lactose surface modification by decantation: Are drug-fine lactose ratios the key to better dispersion of salmeterol xinafoate from lactose-interactive mixtures?

Purpose The role of fine lactose in the dispersion of salmeterol xinafoate (SX) from lactose mixtures was studied by modifying the fine lactose concentration on the surface of the lactose carriers using wet decantation. Methods Fine lactose was removed from lactose carriers by wet decantation using ethanol saturated with lactose. Particle sizing was achieved by laser diffraction. Fine particle fractions (FPFs) were determined by Twin Stage Impinger using a 2.5% SX mixture, and SX was analyzed by a validated high-performance liquid chromatography method. Adhesion forces between probes of SX and silica and the lactose surfaces were determined by atomic force microscopy. Results FPFs of SX were related to fine lactose concentration in the mixture for inhalation grade lactose samples. Reductions in FPF (2-4-fold) of Aeroflo 95 and 65 were observed after removing fine lactose by wet decantation; FPFs reverted to original values after addition of micronized lactose to decanted mixtures. FPFs of SX of sieved and decanted fractions of Aeroflo carriers were significantly different (p < 0.001). The relationship between FPF and fine lactose concentration was linear. Decanted lactose demonstrated surface modification through increased SX-lactose adhesion forces; however, any surface modification other than removal of fine lactose only slightly influenced FPF. Conclusions Fine lactose played a key and dominating role in controlling FPF. SX to fine lactose ratios influenced dispersion of SX with maximum dispersion occurring as the ratio approached unity.

Wastewater analysis of Census day samples to investigate per capita input of organophosphorus flame retardants and plasticizers into wastewater

The use of organophosphate esters (PFRs) as flame retardants and plasticizers has increased due to the ban of some brominated flame retardants. There is however some concern regarding the toxicity, particularly carcinogenicity and neurotoxicity, of some of the PFRs. In this study we applied wastewater analysis to assess use of PFRs by the Australian population. Influent samples were collected from eleven wastewater treatment plants (STPs) in Australia on Census day and analysed for PFRs using gas chromatography coupled with mass spectrometry (GC-MS). Per capita mass loads of PFRs were calculated using the accurate Census head counts. The results indicate that tris(2-butoxyethyl) phosphate (TBOEP) has the highest per capita input into wastewater followed by tris(2-chloroisopropyl) phosphate (TCIPP), tris(isobutyl) phosphate (TIBP), tris(2-chloroethyl) phosphate (TCEP) and tris(1,3-dichloroisopropyl) phosphate (TDCIPP). Similar PFR profiles were observed across the Australian STPs and a comparison with European and U.S. STPs indicated similar PFR concentrations. We estimate that approximately 2.1 mg person−1 day−1 of PFRs are input into Australian wastewater which equates to 16 tonnes per annum.

Bayesian predictive modeling and comparison of oil samples

Statistical comparison of oil samples is an integral part of oil spill identification, which deals with the process of linking an oil spill with its source of origin. In current practice, a frequentist hypothesis test is often used to evaluate evidence in support of a match between a spill and a source sample. As frequentist tests are only able to evaluate evidence against a hypothesis but not in support of it, we argue that this leads to unsound statistical reasoning. Moreover, currently only verbal conclusions on a very coarse scale can be made about the match between two samples, whereas a finer quantitative assessment would often be preferred. To address these issues, we propose a Bayesian predictive approach for evaluating the similarity between the chemical compositions of two oil samples. We derive the underlying statistical model from some basic assumptions on modeling assays in analytical chemistry, and to further facilitate and improve numerical evaluations, we develop analytical expressions for the key elements of Bayesian inference for this model. The approach is illustrated with both simulated and real data and is shown to have appealing properties in comparison with both standard frequentist and Bayesian approaches

Volatile components associated with bacterial spoilage of tropical prawns

Analysis of headspace volatiles by gas chromatography/mass spectrometry from king (Penaeus plebejus), banana (P. merguiensis), tiger (P. esculentus/semisulcatus) and greasy (Metapenaeus bennettae) prawns stored in ice or ice slurry, which is effectively an environment of low oxygen tension, indicated the presence of amines at the early stages of storage (less than 8 days) irrespective of the nature of the storage media. Esters were more prevalent in prawns stored on ice (normal oxygen conditions) at the latter stages of storage (more than 8 days) and were only produced by Pseudomonas fragi, whereas sulphides and amines occurred whether the predominant spoilage organism was Ps.fragi or Shewanella putrefaciens. The free amino acid profiles of banana and king prawns were high in arginine (12–14%) and low in cysteine (0.1–0.17%) and methionine (0.1–0.2%). Filter sterilised raw banana prawn broth inoculated with a total of 15 cultures of Ps. fragi and S. putrefaciens and incubated for two weeks at 5°C, showed the presence of 17 major compounds in the headspace volatiles analysed using gas chromatography/mass spectrometry (GC/MS). These were mainly amines, sulphides, ketones and esters. Principal Component Analysis of the results for the comparative levels of the volatiles produced by pure cultures, inoculated into sterile prawn broth, indicated three subgroupings of the organisms; I, Ps. fragi from a particular geographic location; II, S. putrefaciens from another geographic location; and III, a mixture of Ps. fragi and S. putrefaciens from different geographic locations. The sensory impression created by the cultures was strongly related to the chemical profile as determined by GC/MS. Organisms, even within the same subgrouping classified as identical by the usual tests, produced a different range of volatiles in the same uniform substrate.

Identification of the Sex Pheromone of Holotrichia Reynaudi

The male attractant pheromone of the scarab beetle Holotrichia reynaudi, an agricultural pest native to southern India, was extracted from abdominal glands of females with hexane and analyzed by gas chromatography– mass spectrometry. Field testing of the candidate chemicals, indole, phenol, and anisole, both alone and as binary mixtures, led us to conclude that anisole was the major component of the sex pheromone. Neither male nor female beetles were attracted to indole or phenol on their own. Similarly, when indole and anisole were combined, the attractiveness of the solution did not increase over that obtained with anisole alone. However, combination of phenol and anisole did alter the attractiveness of anisole, with fewer male beetles attracted to the binary mixture than to anisole on its own. The behavior of female beetles was not altered by any of the chemicals tested. Anisole is also the sex pheromone of H. consanguinea, making this the first known example of two melolonthine scarabs sharing the same pheromone.

Differentiation of Bordetella avium and Related Species by Cellular Fatty Acid Analysis

The fatty acids of 18 strains of Bordetella avium, 3 strains of Alcaligenes faecalis, 5 strains of Bordetella bronchiseptica, and 12 strains of a B. avium-like organism were examined by gas chromatography-mass spectrometry. The presence of a significant amount of the acid 2-OH C14:0 characterized B. avium and the B. avium-like organism. B. avium and the B. avium-like organism differed in their relative concentrations of C16:1 and 3-OH C14:0 acids. B. bronchiseptica and A. faecalis were distinguishable by comparison of the relative concentrations of C18:0 and C18:1 acids.

(Z)-11-Hexadecenal and (3Z,6Z,9Z)-Tricosatriene: Sex Pheromone Components of the Red Banded Mango Caterpillar Deanolis sublimbalis

The sex pheromone of the red banded mango caterpillar, Deanolis sublimbalis (Lepidoptera: Crambidae), a serious pest of the mango Mangifera indica (Anacardiaceae) in India and Southeast Asia and a recent invader into northern Australia, has been identified. Three candidate compounds were identified from pheromone gland extracts of female moths, using gas chromatography (GC), GC-electroantennographic detection and GC-mass spectrometric analyses, in conjunction with dimethyldisulfide derivatization. Field bioassays established that both (Z)-11-hexadecenal (Z11-16:Ald) and (3Z,6Z,9Z)-tricosatriene (3Z,6Z,9Z-23:Hy) were required for attraction of male D. sublimbalis moths, and 1,000 μg of a 1:1 mix of Z11-16:Ald and 3Z,6Z,9Z-23:Hy was more attractive to male moths than caged virgin females. However, the binary blend was only attractive when the isomeric purity of the monounsaturated aldehyde was >99%, suggesting that the (E)-isomer was inhibitory. Although (Z)-11-hexadecen-1-ol (Z11-16:OH) was tentatively identified in gland extracts, the addition of this compound to the binary blend did not increase the numbers of moths captured. The pheromone can now be used in integrated pest management strategies.