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Low-temperature pyrolysis of biomass produces a product known as biochar. The incorporation of this material into the soil has been advocated as a C sequestration method. Biochar also has the potential to influence the soil N cycle by altering nitrification rates and by adsorbing NH₄⁺ or NH₃. Biochar can be incorporated into the soil during renovation of intensively managed pasture soils. These managed pastures are a significant source of N₂O, a greenhouse gas, produced in ruminant urine patches. We hypothesized that biochar effects on the N cycle could reduce the soil inorganic-N pool available for N₂O-producing mechanisms. A laboratory study was performed to examine the effect of biochar incorporation into soil (20 Mg ha⁻¹) on N₂O-N and NH₃–N fluxes, and inorganic-N transformations, following the application of bovine urine (760 kg N ha⁻¹). Treatments included controls (soil only and soil plus biochar), and two urine treatments (soil plus urine and soil plus biochar plus urine). Fluxes of N₂O from the biochar plus urine treatment were generally higher than from urine alone during the first 30 d, but after 50 d there was no significant difference (P = 0.11) in terms of cumulative N₂O-N emitted as a percentage of the urine N applied during the 53-d period; however, NH₃–N fluxes were enhanced by approximately 3% of the N applied in the biochar plus urine treatment compared with the urine-only treatment after 17 d. Soil inorganic-N pools differed between treatments, with higher NH₄⁺ concentrations in the presence of biochar, indicative of lower rates of nitrification. The inorganic-N pool available for N₂O-producing mechanisms was not reduced, however, by adding biochar.

Twelve cattle were kept for three days in a circular area of 16 m radius on short pasture and fed with freshly-cut pasture. Ammonia (NH₃) emissions from the urine and dung excreted by the cattle were measured with a micrometeorological mass-balance method, during the cattle presence and for 10 subsequent days. Daily-integrated emission rates peaked on Day 3 of the experiment (last day of cattle presence) and declined steadily for five days thereafter. Urine patches were the dominant sources for these emissions. On Day 9, a secondary emissions peak occurred, with dung pats likely to be the main sources. This interpretation is based on simultaneous observations of the pH evolution in urine patches and dung pats created next to the circular plot. Feed and dung samples were analysed to estimate the amounts of nitrogen (N) ingested and excreted. Total N volatilised as NH₃ was 19.8 (± 0.9)% of N intake and 22.4 (± 1.3)% of N excreted. The bimodal shape of the emissions time series allowed to infer separate estimates for volatilisation from urine and dung, respectively, with the result that urine accounted for 88.6 (± 2.6)% of the total NH₃ emissions. The emissions from urine represented 25.5 (± 2.0)% of the excreted urine-N, while the emissions from dung amounted to 11.6 (± 2.7)% of the deposited dung-N. Emissions from dung may have continued after Day 13 but were not resolved by the measurement technique. A simple resistance model shows that the magnitude of the emissions from dung is controlled by the resistance of the dung crust. © Author(s) 2013.

Aims Ammonia (NH 3 ) can be volatilised from the soil surface following the surface application of nitrogenous fertilisers or ruminant urine deposition. The volatilisation of NH 3 is of agronomic and environmental concern, since NH 3 -N is a form of reactive nitrogen. Ammonia adsorption onto biochar has the potential to mitigate NH 3 losses, but to date no studies have examined the potential for reducing NH 3 losses when biochar is present in the soil matrix. Methods We used 15 N-enriched urine to examine the effect of incorporating a wood based low-temperature biochar into soil on NH 3 volatilisation. Then, we extracted the urine-treated biochar and compared its potential to act as a plant N source with fresh biochar, while growing ryegrass ( Lolium perenne ). Results The NH 3 volatilisation from 15 N-labelled ruminant urine, applied to soil, was reduced by 45% after incorporating either 15 or 30 t ha −1 of biochar. When the urine-treated biochar particles were transferred into fresh soil, subsequent plant growth was not affected but the uptake of 15 N in plant tissues increased, indicating that the adsorbed-N was plant available. Conclusions Our results show that incorporating biochar into the soil can significantly decrease NH 3 volatilisation from ruminant urine and that the NH 3 -N adsorbed onto the biochar is bioavailable. Further studies are now required to assess the temporal dynamics of the N pools involved.

Numerous disclosure studies have demonstrated that individuals randomly assigned to write about emotional topics evidence improved physical health compared with those who write about superficial topics. The writing samples from three previously published studies of 74 first-year students, 50 upper-division students, and 59 maximum-security prisoners were reanalyzed using Latent Semantic Analysis (LSA) to explore possible relationships of writing content and style to changes in frequency of physician visits following the disclosure intervention. LSA revealed that flexibility in the use of common words--particularly personal pronouns--when writing about traumatic memories was related to positive health outcomes. The findings point to the importance of the role of discussing the self and social relationships in writing and, at the same time, to the remarkable potential of techniques such as LSA.

Bathochordaeus mcnutti sp. nov. is described from the mesopelagic northeast Pacific Ocean (Monterey Bay, California, USA). Larvaceans in the genus Bathochordaeus are large, often abundant zooplankters found throughout much of the world ocean, but until recently it was unclear whether more than a single species of Bathochordaeus existed. Using remotely operated vehicles, we have made hundreds of in situ observations, compiled two decades of time-series data, and carefully collected enough specimens to determine that three species of Bathochordaeus occur in Monterey Bay: B. charon (Chun), B. stygius (Garstang), and B. mcnutti sp. nov. Bathochordaeus mcnutti is readily distinguished from its two congeners by the distinct blue outline visible around the periphery of its tail, and by other aspects of its morphology, ecology, and genetics. The abundance of larvaceans means they are ecologically important as particle processors. Species within the genus, Bathochordaeus , comprise the largest of described larvaceans.

Mineral prospectivity maps were produced for gold in two greenstone belts in the Superior geological province in Ontario, Canada, as part of the Metal Earth Project in the Laurentian University, Sudbury, Ontario. These maps, created using the random forest machine learning algorithm, cover the well-endowed Matheson area, which is in the Abitibi sub-province, and the less fertile Dryden area, which is in the Wabigoon sub-province. Newly identified areas for follow-up gold exploration are associated with major faults and 3D geophysical data comprising resistivity, density and susceptibility data. In addition, observations not used in mineral prospectivity mapping based on magnetotelluric, seismic and isotopic data may in part describe why the Matheson greenstone belt is more fertile with respect to gold mineralization than the Dryden greenstone belt. These observations suggest that the Matheson area has major transcurrent faults associated with conductive zones that reach the surface, many of which are associated with deeply penetrating, vertical faults. The isotopic signature of the Matheson crust also suggests it is juvenile, whereas the Dryden area is older.

Liming has been mooted as a mitigation option for lowering soil N₂O emissions. This study investigated the effect of soil pH and soil water content on N₂O and N₂ emissions following the addition of synthetic urine (500 kg N ha⁻¹) containing ¹⁵N-labeled urea-N. Soil pH treatments ranged from 4.7 to 7.2 with either saturated or field capacity soil. Dinitrogen and N₂O fluxes were measured from soil cores kept on water tension tables for 85 d following urine-N addition. Soil inorganic N transformations were also monitored over time by destructively sampling soil cores on five occasions over the 85 d. At field capacity, soil pH affected the N₂O fluxes with the lowest cumulative N₂O fluxes at soil pH 5.9. Nitrous oxide losses ranged from <0.1 to 0.4% of ¹⁵N applied in the field capacity treatment but this increased to be 0.4 to 1.7% of the ¹⁵N applied in the saturated treatment. Dinitrogen fluxes were low (<23 ng N₂–N cm⁻² h⁻¹) at field capacity but exceeded 4000 ng N₂–N cm⁻² h⁻¹ under saturated conditions. Cumulative N₂ fluxes increased with increasing soil pH in the saturated soil. The flux ratio of N₂O-N/(N₂O-N + N₂–N) remained high (0.68–0.71) under the field capacity treatment but decreased with time from 0.64 to 0.16 in the saturated treatment. This study suggests that while the use of soil liming has merit for lowering N₂O emissions from urine patches where soils are at field capacity, the resulting NO₃–N will be susceptible to enhanced rates of N₂O and N₂ loss if the soils are wetted up beyond field capacity.

BACKGROUND AND AIMS: Relationships between the chemical composition and the sensory perception of red wines are generally poorly understood. In New Zealand, the vineyard area of Pinot Noir has increased markedly and wines from this red cultivar now constitute a significant proportion of total production. The aim of this study was to identify aroma compounds of major sensory significance in New Zealand Pinot Noir wines. METHODS AND RESULTS: The concentration of 34 aroma chemicals in 32 New Zealand Pinot Noir wines was quantified using three separate solid‐phase microextraction‐GC‐MS methods. Relationships between these chemical data and sensory data obtained from the same wines were investigated with canonical correlation analysis. Subsequently, correlation results were validated with addition/omissions tests. Ethyl octanoate was found to increase red cherry aroma, the combination of ethyl octanoate and ethyl decanoate enhanced black cherry aroma, and 2‐phenyl ethanol increased violet aroma. Benzaldehyde altered Pinot Noir aroma but its effect on specific attributes was unclear. CONCLUSIONS: The influence of benzaldehyde, ethyl octanoate and 2‐phenyl ethanol on the aroma of Pinot Noir wine was consistent with previous studies conducted on Merlot and Cabernet Sauvignon wines. This indicated that the contribution of these compounds is similar in a range of red wines. Ethyl decanoate appeared to act as an aroma enhancer compound when in combination with ethyl octanoate. SIGNIFICANCE OF THE STUDY: Improved knowledge of key aroma and flavour components and the factors that influence their concentration is required to allow producers to manipulate better sensory characteristics to meet the preferences of specific markets. This study provides new information on important aroma compounds in New Zealand Pinot Noir which can lead to future research on modulating factors.

Selected chemical, biochemical and biological properties of mineral soil (0-30 cm) were measured under a 19 year old forest stand (mixture of Pinus ponderosa and Pinus nigra) and adjacent unimproved grassland at a site in South Island, New Zealand. The effects of afforestation on soil properties were confined to the 0-10 cm layer, which reflected the distribution of fine roots (< 2 mm) in the soil profile. Concentrations of organic C, total N and P and all organic forms of P were lower under the forest stand, while concentrations of inorganic P were higher under forest compared with grassland, supporting the previously described suggestion that afforestation may promote mineralisation of soil organic matter and organic P. On the other hand, microbial biomass C and P, soil respiration and phosphatase enzyme activity were currently all lower and the metabolic quotient was higher in soil under forest compared with grassland, which is inconsistent with increased mineralisation in the forest soil. Reduced biological fertility by afforestation may be mainly attributed to changes in the quantity, quality and distribution of organic matter, and reduction in pH of the forest soil compared with the grassland soil. We hypothesize that the lower levels of C, N and organic P found in soil under forest are due to enhanced microbial and phosphatase activity during the earlier stages of forest development. Forest floor material (L and F layer) contained large amounts of C, N and P, together with high levels of microbial and phosphatase enzyme activity. Thus, the forest floor may be an important source of nutrients for plant growth and balance the apparent reduction in C, N and P in mineral soil through mineralisation and plant uptake.

Objective: To determine the effect of concomitant administration of prophylactic indomethacin and early enteral feeds on the risk of spontaneous intestinal perforation (SIP) in extremely low-birth-weight (ELBW) infants, and to describe the variation in prophylactic indomethacin use in Canada. Study design: A retrospective cohort study of 4268 ELBW infants born at <30 weeks’ gestation admitted to Canadian neonatal units between 2010 and 2014 was conducted. Prophylactic indomethacin (I+ or I−, administered within 24 h) and early feeding (E+ or E−, initiated in the first 2 days) exposures were studied concurrently and independently. The primary outcomes were SIP and death before discharge. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated. Results: Compared with the I−/E+ reference group ( n= 1829), infants in I+/E+ ( n= 285; aOR 2.92, 95% CI 1.41 to 6.08) and I+/E− ( n= 213; aOR 2.84, 95% CI 1.35 to 5.98) groups had higher odds of SIP, whereas those in the I−/E− group had similar odds ( n= 1941; aOR 1.37, 95% CI 0.88 to 2.14). Odds of SIP were higher in the indomethacin exposed group (I+) compared with the unexposed (I−) group when controlled for early feeding (aOR 2.43, 95% CI 1.41 to 4.19), but not in the early feeding group when controlled for indomethacin. The use of prophylactic indomethacin ranged from 0% usage in 13 sites to 78% use in one site. Conclusion: Prophylactic indomethacin was associated with increased odds of SIP independently from early feeding in this cohort; however, early enteral feeding was not associated with SIP. Marked variation in the use of prophylactic indomethacin was identified.