1.Comparison and validation of 2 analytical methods for the determination of free fatty acids in dairy products by gas chromatography with flame ionization detection.
Mannion DT1, Furey A2, Kilcawley KN3. J Dairy Sci. 2016 Apr 13. pii: S0022-0302(16)30178-3. doi: 10.3168/jds.2015-10795. [Epub ahead of print]
Accurate quantification of free fatty acids (FFA) in dairy products is important for quality control, nutritional, antimicrobial, authenticity, legislative, and flavor purposes. In this study, the performance of 2 widely used gas chromatographic flame ionization detection methods for determination of FFA in dairy products differing in lipid content and degree of lipolysis were evaluated. We used a direct on-column approach where the isolated FFA extract was injected directly and a derivatization approach where the FFA were esterified in the injector to methyl esters using tetramethylammonium hydroxide as a catalyst. A comprehensive validation was undertaken to establish method linearity, limits of detection, limits of quantification, accuracy, and precision. Linear calibrations of 3 to 700 mg/L (R2 > 0.999) and 20 to 700 mg/L (R2 > 0.997), and limits of detection and limits of quantification of 0.7 and 3 mg/L and 5 and 20 mg/L were obtained for the direct injection on-column and the derivatization method, respectively.
2.Novel integrated mechanical biological chemical treatment (MBCT) systems for the production of levulinic acid from fraction of municipal solid waste: A comprehensive techno-economic analysis.
Sadhukhan J1, Ng KS2, Martinez-Hernandez E3. Bioresour Technol. 2016 Apr 9. pii: S0960-8524(16)30517-X. doi: 10.1016/j.biortech.2016.04.030. [Epub ahead of print]
This paper, for the first time, reports integrated conceptual MBCT/biorefinery systems for unlocking the value of organics in municipal solid waste (MSW) through the production of levulinic acid (LA by 5wt%) that increases the economic margin by 110-150%. After mechanical separation recovering recyclables, metals (iron, aluminium, copper) and refuse derived fuel (RDF), lignocelluloses from remaining MSW are extracted by supercritical-water for chemical valorisation, comprising hydrolysis in 2wt% dilute H2SO4 catalyst producing LA, furfural, formic acid (FA), via C5/C6 sugar extraction, in plug flow (210-230°C, 25bar, 12s) and continuous stirred tank (195-215°C, 14bar, 20min) reactors; char separation and LA extraction/purification by methyl isobutyl ketone solvent; acid/solvent and by-product recovery. The by-product and pulping effluents are anaerobically digested into biogas and fertiliser. Produced biogas (6.4MWh/t), RDF (5.4MWh/t), char (4.
3.A 10-Year Retrospective Analysis of Methyl Aminolevulinate Photodynamic Therapy Consultation at the Hospital de Braga.
Brito C1, Resende C2, Oliveira P3. Dermatol Ther (Heidelb). 2016 Apr 16. [Epub ahead of print]
INTRODUCTION: Photodynamic therapy (PDT) is a well-established treatment for actinic keratosis (AK), basal cell carcinoma (BCC), and Bowen's disease (BD). The object of this study was to describe the results of a retrospective analysis of patients treated with methyl aminolevulinate PDT (MAL-PDT) with red light, over the past decade at the Hospital de Braga (Braga, Portugal).
4.Prior activation of inositol 1,4,5-trisphosphate receptors suppresses the subsequent induction of long-term potentiation in hippocampal CA1 neurons.
Fujii S1, Yamazaki Y2, Goto J3, Fujiwara H2, Mikoshiba K4. Learn Mem. 2016 Apr 15;23(5):208-20. doi: 10.1101/lm.041053.115. Print 2016 May.
We investigated the role of inositol 1,4,5-trisphosphate receptors (IP3Rs) activated by preconditioning low-frequency afferent stimulation (LFS) in the subsequent induction of long-term potentiation (LTP) in CA1 neurons in hippocampal slices from mature guinea pigs. Induction of LTP in the field excitatory postsynaptic potential or the population spike by the delivery of high-frequency stimulation (HFS, a tetanus of 100 pulses at 100 Hz) to the Schaffer collateral-commissural pathway to CA1 neuron synapses was suppressed when group I metabotropic glutamate receptors (mGluRs) were activated prior to the delivery of HFS. LTP induction was also suppressed when CA1 synapses were preconditioned 60 min before HFS by LFS of 1000 pulses at 1 Hz and this effect was inhibited when the test stimulation delivered at 0.05 Hz was either halted or applied in the presence of an antagonist ofN-methyl-d-aspartate receptors, group I mGluRs, or IP3Rs during a 20-min period from 20 to 40 min after the end of LFS.