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Manure storage is a well known source of anthropogenic ammonia emissions and has been the subject of numerous studies in Western Europe and the U.S. However, climate and manure management practices differ widely in Canada. In this study, commercial dairy and swine manure storages covered by floating geomembranes were monitored for periods exceeding six months in Canada. The swine manure storage emitted negligible amounts of ammonia over the summer, from 5.8 x 10-3 to 0.13 µg m-2 s-1, much lower than emission rates found in the literature for swine manure, which ranged between 45 and 875 µg m-2 s-1. The most substantial ammonia emissions at the swine facility occurred during manure mixing operations. A structural difference in the covering technology at the dairy manure storage rendered it less airtight than at the swine manure storage. The dairy manure storage emitted more substantial amounts of ammonia when unfrozen (91 to 171 µg m-2 s-1 then when frozen during winter (1.9 to 16 µg m-2 s-1). These emission rates are lower in magnitude than values found in the literature for dairy manure, which ranged between 10 and 864 µg m-2 s-1. Average relative uncertainties of emission rate measurements were estimated to be 8%, 26%, and 26%, respectively, for unfrozen dairy manure, frozen dairy manure, and swine manure. [ABSTRACT FROM AUTHOR]

Bacterial exopolysaccharides (EPS) are extracellular polymer-based substances recently defined as potential plant biostimulants, as they can increase nutrient uptake, water retention, and resistance to abiotic stress. As sugar-based substances, the bacteria producing them need to grow in a sugar-rich substrate. Hence, some agri-food by-products could be used as suitable carbon sources for EPS production as a cost-effective and more sustainable alternative to conventional substrates. Thus, this study aimed to produce EPS from specific bacterial strains through solid-state fermentation (SSF) using agri-food waste as a low-cost substrate. Six residues and five bacterial strains were tested in a lab-scale SSF system. From the assessed substrate-strain combinations, Burkholderia cepacia with ginger juice waste (GJW) resulted in the most promising considering several process parameters (EPS production, cumulative oxygen consumption, biomass growth, reducing sugars consumption). Also, dynamic monitoring of the system allowed for establishing 5 days as a suitable fermentation time. Then, using response surface methodology (Box-Behnken design), the process was optimised based on airflow rate (AF), inoculum size (IS), and micronutrient concentration (MN). In this stage, the best conditions found were at 0.049 (± 0.014) L h -1 per gram of dry matter (DM) for AF, 8.4 (± 0.9) E + 09 CFU g -1 DM for IS, and 0.07 (± 0.01) mL g -1 DM for MN, reaching up to 71.1 (± 3.2) mg crude EPS g -1 DM. Results show the potential of this approach to provide a new perspective on the value chain for the agri-food industry by introducing it to a circular economy framework., (© 2024. The Author(s).)

Adolescent idiopathic scoliosis (AIS) is a multifactorial disorder characterized by a tridimensional deformation of the spine. AIS pathophysiology is still unclear and its aetiology is unknown. Results from several studies revealed balance control alterations in adolescents with AIS suggesting cortical sensorimotor processing impairments. Studies assessing cortical activity involved in balance control revealed an increase in alpha peak frequency (APF), which is a neurophysiological marker of thalamo-cortical transmission, related to a more challenging balance task. The objective of this study is to assess APF of adolescents with AIS during balance control in upright standing posture using electroencephalography (EEG). EEG was recorded in 16 girls with AIS and 15 control girls in normal standing posture on a force platform. The participants stood upright for 2 min with eyes open and 2 min with eyes closed. Fast Fourier transformations of EEG data were calculated to obtain APF. Balance performances were assessed through the area of an ellipse covering the center of pressure (COP) displacement and the root mean square value of the COP velocity. Compared to the control group, APF was higher in the AIS group at central, frontal, parietal and occipital regions. Further, COP analyses did not reveal any difference between AIS and control groups. A higher APF may indicate the need for increased cortical processing to maintain balance control in normal upright standing in adolescents with AIS compared to healthy controls. We suggest that this may be a compensatory strategy to overcome balance control challenges., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Immunoaffinity extraction combined with high-performance liquid chromatography (HPLC) with fluorescence detection was developed to determine Fumonisin B1 (FB1) in duck tissues. The method was linear over a concentration range of 0.013-0.250 microg of FB1/g of liver, kidney and muscle. The limit of quantification was 0.013 microg FB1/g in tissue. The mean percentage of extraction was 75% for liver and kidney and 53% for muscle. This method can be used in duck for the detection of FB1 contamination after exposure, the liver being the most contaminated tissue.