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Larvae of the goldenrod gall fly, Eurosta solidaginis, rely on a freeze tolerance strategy to survive the sub‐zero temperatures of Canadian winter. Critical to their survival is the accumulation of polyol cryoprotectants and global metabolic rate depression, both of which require the regulation of glycolysis and reorganization of carbohydrate metabolism. This study explored the role that pyruvate kinase (PK) regulation plays in this metabolic reorganization. PK was purified from control (5 °C‐acclimated) and frozen (−15 °C‐acclimated) larvae and enzyme kinetic properties, structural stability, and post‐translational modifications were examined in both enzyme forms. The Km phosphoenolpyruvate (PEP) of frozen PK was 20% higher than that of control PK, whereas the Vmax of frozen PK was up to 50% lower than that of control PK at the lowest assay temperature, suggesting inhibition of the enzyme during the winter. Additionally, the activity and substrate affinity of both forms of PK decreased significantly at low assay temperatures, and both forms were regulated allosterically by a number of metabolites. Pro‐Q™ Diamond phosphoprotein staining and immunoblotting experiments demonstrated significantly higher threonine phosphorylation of PK from frozen animals while acetylation and methylation levels remained constant. Together, these results indicate that PK exists in two structurally distinct forms in E. solidaginis. In response to conditions mimicking the transition to winter, PK appears to be regulated to support metabolic rate depression, the accumulation of polyol cryoprotectants, and the need for extended periods of anaerobic carbohydrate metabolism to allow the animal to survive whole‐body freezing. [ABSTRACT FROM AUTHOR]

Methane emission quantification from gas migration (GM) and surface casing vent flow (SCVF) is needed to support strategic methane reduction targets and mitigate explosion and groundwater quality risks. This paper assessed which of 451 990 Alberta oil and gas wells should have been (or will be) tested for SCVF and/or GM according to regulations, and compared the results with the provincial GM testing database. As of 2017, GM testing was required on 3.5%, and reported for 0.75%, of Alberta's energy wells. Similarly, SCVF testing was required on 58.2%, and reported for 6.2%, of all wells. An estimated 14.5% of all wells were legally abandoned before GM and SCVF testing regulations existed. All of the remaining wells will require SCVF testing prior to legal abandonment, and an estimated 32.9% to 75.5% of the total will not require GM testing before abandonment based on current regulations. The cumulative number of 'serious' GM reports that have remained open since submission has continuously been increasing each year, which contradicts the requirement for repair within 90 days, suggesting regulations are not enforced. The GM testing procedure is inadequate for quantitative testing. We conclude that fugitive methane emissions, and in particular gas migration, are not well constrained in Alberta. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Introduction: Pain is a motivational stimulus that influences motor behaviour. To identify whether motor adaptation may be a purposeful strategy to avoid pain-provocative movements, we investigated kinematic adaptations to experimentally induced pain modulated by lumbar flexion. Methods: Sixteen healthy adults performed a lifting task consisting of 15 sets of 10 cycles each. Pain was induced in the lumbosacral region (sets 3-13) using electrical stimulation modulated in real-time3 to induce pain intensity of 5/10 when lumbar flexion was equal or higher than the peak flexion recorded at baseline. Repeated-measures ANOVA followed by post-hoc analyses were conducted to assess changes in lumbar kinematics between baseline (sets 1-2), early adaptation (sets 3-4), late adaptation (sets 12-13), and post-pain (sets 14-15). Results: Compared to baseline, participants reduced lumbar flexion in the late adaptation (p < 0.05) and post-pain (p < 0.05), and increased lumbar extension during both early (p < 0.05) and late adaptation (p < 0.05). The reduction of lumbar flexion during late adaptation was inversely associated to reported pain intensity (r = -0.52, p < 0.05). Discussion: When pain is modulated by lumbar flexion, individuals increase lumbar extension and learn to reduce lumbar flexion over time to limit pain. The adopted movement strategy (reduction in lumbar flexion) was maintained after pain resolution. Process evaluation: Pain perception could be affected by habituation to electrical stimulation and exercise-induced hypoalgesia. To ensure consistency across trials, the pain threshold was regularly reassessed. [ABSTRACT FROM AUTHOR]

Solvent effects on the 1H and 13C NMR chemical shifts of some lactones: β-propiolactone, γ-butyrolactone, δ-valerolactone and ε-caprolactone, as well as lactams: azetidin-2-one, pyrrolidin-2-one, δ-valerolactam and ε-caprolactam have been investigated and discussed in a wide range of solvents. The experimental results were compared with density functional calculations using a large basis set. Solvent effects were computed by means of an integrated approach including the polarizable continuum model and an optimum number of explicit solvent molecules surrounding the solute. The agreement between computed and experimental chemical shifts fully validates our integrated approach. In order to quantify and elucidate the origin of the solvent effects on the 1H and 13C chemical shifts of the selected compounds, a multi-linear regression analysis has been carried out using the empirical Kamlet-Abboud-Taft solvatochromic parameters. It has been found that there is a good correlation between the solvent-induced chemical shifts of 13C and the π* scale of solvent dipolarity polarizability. 1H chemical shifts are affected mainly by the dipolarity-polarizability and the basicity of the solvent. An excellent agreement has been obtained between the calculated and the experimental data. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Recent evidence indicates that tyrosine phosphorylation may play important roles in retinal photoreceptor rod outer segments (ROS). We investigated the tyrosine phosphorylation of endogenous proteins in isolated bovine ROS. Several proteins with apparent molecular masses of 31, 39, 60, 83, 90, 97, 120, 140, and 180 kDa were tyrosine-phosphorylated in ROS incubated with Mg2+, ATP, and orthovanadate. Several tyrosine kinase inhibitors significantly inhibited tyrosine phosphorylation of these proteins in ROS. The 39- and 60-kDa tyrosine-phosphorylated proteins were identified as the α subunit of the G protein transducin (Tα) and the tyrosine kinase Src, respectively. The presence of Src and tyrosine kinase activity in bovine ROS was confirmed by their cofractionation with rhodopsin and Tα on continuous sucrose gradients. Several tyrosine-phosphorylated proteins, including Src, coimmunoprecipitated with Tα. The association of Src with Tα was detected in the absence of tyrosine phosphorylation, but was enhanced with increased tyrosine phosphorylation of ROS. Moreover, tyrosine kinase activity also associated with Tα was sevenfold higher under tyrosine-phosphorylating conditions. The recovery of transducin by hypotonic GTP extraction from tyrosine-phosphorylated ROS was significantly less than that from nonphosphorylated ROS. We localized the site on Tα phosphorylated by Src to the amino-terminal half by limited tryptic digests, and further mapped it by ion trap mass spectrometry to Tyr142 in the helical domain of Tα. Tα was also tyrosine-phosphorylated in vivo in rat retina, but this phosphorylation was not affected by light. [ABSTRACT FROM AUTHOR]

Abstract: Increasing evidence indicates that tyrosine phosphorylation, controlled by the concerted action of tyrosine kinases and protein tyrosine phosphatases (PTPs), plays important roles in retinal photoreceptor rod outer segments (ROS). We characterized PTP activity in isolated bovine ROS that is significantly inhibited by orthovanadate. Incubating ROS in the presence of exogenous Mg2+, ATP, and orthovanadate dramatically enhanced the tyrosine phosphorylation of several endogenous proteins. SHP-2, a PTP with two SH2 domains, was identified in ROS by immunoblot analysis and was found to associate with ROS membranes. Immunocytochemisry showed localization of SHP-2 in photoreceptor outer segments and possibly in the outer plexiform, inner nuclear, and inner plexiform cell layers of the retina as well. SHP-2 associated with transducin-α and a 97-kDa tyrosine-phosphorylated protein in ROS, suggesting the formation of a multimeric signaling complex. Based on its association with transducin-α and a 97-kDa protein, SHP-2 may regulate the tyrosine phosphorylation of endogenous proteins, including transducin-α, and may play a significant role in a novel signaling pathway in photoreceptors. [ABSTRACT FROM AUTHOR]

A general subdomain integral approach to finite-element analysis is presented, based on the application of the principle of conservation of energy to steady-state heat transfer in solids. The principal object of the paper is to use this method to formulate equations for a general three-dimensional distorted brick element. First the three-dimensional solution domain is divided into hexahedron elements. Each node is surrounded by a control volume so that the entire solution domain is filled with non-overlapping, three-dimensional control volumes. Each element in the global co-ordinate system is mapped onto a master cubical element in a local isoparametric system. The temperature within each element is interpolated using trilinear shape functions. An energy balance is then performed on each control volume as element matrices are assembled into the global system matrix. Several test problems are presented both to demonstrate the method and to assess its accuracy. [ABSTRACT FROM AUTHOR]

An abstract of the conference paper "Antenatal and postnatal evolution of a large posterior encephalocele," by S. Richa and colleagues is presented.

An abstract of the conference paper "Parents reaction at diagnosis of fetal anomalies," by S. Richa and colleagues is presented.

An abstract of the conference paper "Complex placental image: evolution and diagnosis," by A. K. Kesrouani and colleagues is presented.

An abstract of the conference paper "Private vs public obstetrical ultrasound in Lebanon," by A. K. Kesrouani and colleagues is presented.

An abstract of the conference paper "Choroid plexus cyst: how much do we need to worry," by A. K. Kesrouani, and colleagues is presented.