University of Alberta

About: University of Alberta is a education organization based out in Edmonton, Alberta, Canada. It is known for research contribution in the topics: Population & Health care. The organization has 65403 authors who have published 154847 publications receiving 5358338 citations. The organization is also known as: Ualberta & UAlberta.

Depression, Self-Esteem, and Anger in Emerging Adulthood: Seven-Year Trajectories.

Abstract: This study used a school-based community sample (N=920) to examine trajectories of depressive symptoms, self-esteem, and expressed anger in the critical years of emerging adulthood (ages 18-25). Using data from 5 waves, the authors discovered that multilevel models indicated that, on average, depressive symptoms and expressed anger declined, whereas self-esteem increased. Between-persons predictors of variability in trajectories included gender (gender gaps in depressive symptoms and self-esteem narrowed), parents' education, and conflict with parents (depressive symptoms and expressed anger improved fastest in participants with highly educated parents and in those with higher conflict). Across time, increases in social support and marriage were associated with increased psychological well-being, whereas longer periods of unemployment were connected with higher depression and lower self-esteem. Emerging adulthood is a time of improving psychological well-being, but individual trajectories depend on specific individual and family characteristics as well as role changes.

An Abnormal Mitochondrial–Hypoxia Inducible Factor-1α–Kv Channel Pathway Disrupts Oxygen Sensing and Triggers Pulmonary Arterial Hypertension in Fawn Hooded Rats Similarities to Human Pulmonary Arterial Hypertension

Abstract: Background— The cause of pulmonary arterial hypertension (PAH) was investigated in humans and fawn hooded rats (FHR), a spontaneously pulmonary hypertensive strain. Methods and Results— Serial Doppler echocardiograms and cardiac catheterizations were performed in FHR and FHR/BN1, a consomic control that is genetically identical except for introgression of chromosome 1. PAH began after 20 weeks of age, causing death by &60 weeks. FHR/BN1 did not develop PAH. FHR pulmonary arterial smooth muscle cells (PASMCs) had a rarified reticulum of hyperpolarized mitochondria with reduced expression of electron transport chain components and superoxide dismutase-2. These mitochondrial abnormalities preceded PAH and persisted in culture. Depressed mitochondrial reactive oxygen species (ROS) production caused normoxic activation of hypoxia inducible factor (HIF-1α), which then inhibited expression of oxygen-sensitive, voltage-gated K+ channels (eg, Kv1.5). Disruption of this mitochondrial-HIF-Kv pathway impaired oxygen ...

Adult age differences in working memory.

Abstract: Active and passive measures of short-term memory over a large segment of the adult life span were compared. Two hundred twenty-eight volunteers, aged 30 to 99 years, performed the digit span forward and backward task, the Peterson-Peterson task, and a new working memory task in which active manipulation of information is emphasized. Age differences were slight for passive tasks. For the working memory task, significant declines were found between the ages of 60 to 69 and 70+ years. It is suggested that the age differences may be due to a decrease in the flexibility with which processing changes are made.

Mass Transfer Characteristics of Solvent Extraction into a Single Drop at the Tip of a Syringe Needle

Abstract: The amount of a sample compound extracted into a 1-μL drop of n-octane suspended in a stirred aqueous solution from the tip of a microsyringe needle is measured by gas chromatography (GC) as a function of time. The observed extraction rate curve is first order and yields the overall mass transfer coefficient for the sample compound, βo. For a given compound, βo varies linearly with stirring rate. Among the four compounds malathion, 4-methylacetophenone, 4-nitrotoluene, and progesterone, at a given stirring rate, βo is linearly proportional to the diffusion coefficient of the compound (Daq). This supports the film theory of convective−diffusive mass transfer, as opposed to the penetration theory. The relative standard deviation of the GC signal for 4-methylacetophenone after a 1.00 min extraction at 1500 rpm is 1.5%, which suggests that the system exhibits excellent potential as a tool for rapid analysis by solvent extraction/GC.

Quantitative metabolomics using NMR

Abstract: Nuclear magnetic resonance (NMR) spectroscopy can be used to both identify and quantify chemicals from complex mixtures. This can be done semi-automatically by comparing the mixture of interest to a library of reference spectra derived from pure compounds of known concentrations. This particular approach is now being exploited to characterize the metabolomes of many different biological samples in what is called quantitative metabolomics or targeted metabolic profiling. This review describes some of the practical aspects pertaining to NMR-based quantitative metabolomics and highlights some of the strengths, limitations and applications of this particular approach to metabolomics.