Long-term environmental fate of perfluorinated compounds after accidental release at Toronto airport

Perfluorooctane sulfonate (PFOS; a perfluorinated compound or PFC), its salts, and perfluorooctane sulfonyl fluoride have recently been listed in Annex B of the Stockholm Convention due to their widespread presence, persistence, and toxicity. Because of the persistent nature of PFCs, it is generally presumed that the impact of direct discharges of these chemicals on a receiving environment would be long-lasting. However, long-term environmental fate studies based on field measurements are rare. We examined spatial and long-term (9 year) temporal trends of PFCs in water, sediment, fish, and fish liver collected in 2003, 2006, and 2009 from 10 locations spanning ～20 km in Etobicoke and Spring Creeks, where an accidental release of fire fighting foam containing PFOS from nearby Toronto International Airport occurred in 2000. Even a decade after the spill, sediment PFOS concentrations are still elevated in Spring Creek Pond which received the foam discharge; however, the major impact is relatively localized likely due to the stormwater management nature of the pond and the diluting effect of Etobicoke Creek. Fish and fish liver PFOS concentrations at a Spring Creek location downstream of Spring Creek Pond declined by about 70 and 85%, respectively, between 2003 and 2009. PFOS in water at locations further downstream in Etobicoke Creek have declined by >99.99% since the spill; however, the 2009 water and fish levels were ～2-10 times higher than upstream locations likely due to the long-term impact of the spill as well as urbanization. The decrease in the upstream PFOS concentrations likely reflects the reduction of PFOS sources due to phased out production by 3M and regulations on the use of PFOS in fire fighting foams. Field-based sediment/water distribution coefficients (K(D)) and bioaccumulation factors (BAF) were calculated from environmental measurements. Log K(D) values were 0.54-1.65 for perfluoroalkyl sulfonates (PFASs) and 1.00-1.85 for perfluorocarboxylates (PFCAs). Log BAF(fish) ranged from 1.85 to 3.24 for PFASs and 0.88-3.47 for PFCAs, whereas log BAF(fish liver) ranged from 2.1-4.3 for PFASs and 1.0-5.0 for PFCAs.     

Structure and Morphology of Inclusions in 4�� Offcut 4H-SiC Epitaxial Layers

The structure of inclusions and their influence on surface morphology, local strain, and basal plane dislocations were investigated in silicon carbide (SiC) epitaxial layers grown on 4° offcut substrates. On high-resolution x-ray topography images, strain fields were observed surrounding the inclusions. Ultraviolet photoluminescence images revealed the presence of strain-induced dislocations around the inclusions. Micro-Raman and microphotoluminescence spectroscopy showed that the inclusions exhibited a complex structure that consisted of 3C polytype regions and misoriented 4H polytype regions. The resulting lattice deformation typically propagates in the step-flow growth direction and causes distorted surface morphology.     

Materials for multifunctional balloon catheters with capabilities in cardiac electrophysiological mapping and ablation therapy

Developing advanced surgical tools for minimally invasive procedures represents an activity of central importance to improving human health. A key challenge is in establishing biocompatible interfaces between the classes of semiconductor device and sensor technologies that might be most useful in this context and the soft, curvilinear surfaces of the body. This paper describes a solution based on materials that integrate directly with the thin elastic membranes of otherwise conventional balloon catheters, to provide diverse, multimodal functionality suitable for clinical use. As examples, we present sensors for measuring temperature, flow, tactile, optical and electrophysiological data, together with radiofrequency electrodes for controlled, local ablation of tissue. Use of such 'instrumented' balloon catheters in live animal models illustrates their operation, as well as their specific utility in cardiac ablation therapy. The same concepts can be applied to other substrates of interest, such as surgical gloves.     

The effect of ionising radiation on the colour of beef, pork and lamb

The effect of irradiation (0 and 5 kGy) of beef, pork and lamb portions in retail overwrap packs and subsequent storage at 4°C was studied in relation to colour changes. The colour of the exterior surface of beef and pork was measured on the same samples on each day of storage for up to 7 days post irradiation. On day 7 the colour of a freshly cut surface was measured. The colour of both the exterior and a freshly cut surface of lamb, in similar retail overwrap packs was measured at 2, 5 and 7 days, post irradiation, different samples being used on each day of measurement. L* values of irradiated beef increased significantly with storage and a* values for unirradiated samples decreased significantly with storage. For lamb there was a general increase in L* and h(o) values and a decrease in a*, b* and C* values with storage. Analyses of the day 7 data showed statistically significant effects for species on all CIELAB parameters. Irradiation resulted in significantly higher hue angle (h(o)) values and the a*, b* and C* values were significantly higher on the exterior than freshly cut surface. There were a number of statistically significant 2 factor and 3 factor interactions. The role of formation of a carboxyhaem pigment in the colour of irradiated meat is discussed. The problem of interpretation of pigment changes from CIELAB values is highlighted.     

Interrelationships amongst carcass and meat quality characteristics of sheep

The relationships between various carcass and meat quality characteristics of sheep were studied. Relationships were determined by regression, using data obtained from sheep belonging to a wide range of breeds, sex types and slaughter weight (32-62 kg). The chilling rate of the M. longissimus dorsi (LD) post-mortem was negatively correlated with carcass weight (r=-0.42, P<0.01), back fat thickness (r=-0.54, P<0.001) and the cooking loss of the M. infraspinatus (IS) muscle (r=-0.44, P<0.001). Correlation between chilling rate and shear force of the IS muscle was not significant, which was also the case between chilling rate and the cooking loss and shear force of the LD and M. triceps brachii muscles. A positive relationship was observed between total collagen and cooking loss (r=0.34, P<0.05) and between heat-insoluble collagen and cooking loss of the LD muscle (r=0.37, P<0.01). Generally collagen content was positively correlated with lean content and negatively with fat content. Carcass weight was significantly (P<0.001) correlated with intramuscular fat (r=0.61), moisture (r=-0.76), cooking loss (r=-0.49), shear force (r=-0.41) and hue angle (r=-0.41). Shear force was positively associated with cooking loss (r=0.42, P<0.001), but negatively with intramuscular fat content (r=-0.55, P<0.001). Cooking loss was positively correlated with moisture content (r=0.55, P<0.001).     

Les conversations mère-enfant et l'attachement des enfants à la période préscolaire.

This study examines whether mother-child conversation patterns are associated with child attachment classifications at preschool age (N=80). Results revealed that a child's discourse style is similar to that of her or his mother. In comparison with mothers of insecure ambivalent or disorganized children, mothers of secure children made more frequent verbal statements that elaborated emotional content. Mothers of avoidant children were more inclined to minimize emotional content than mothers of secure children. In comparison with other mothers, those with a disorganized child were sharing more frightening and hostile content, or made more verbal statements accompanied by aggressive behaviors. Secure children made more frequent verbal statements that elaborated emotional content than avoidant and disorganized children. Disorganized children made more controlling verbal statements as well as statements accompanied by aggressive or flight behaviors. Finally, our results showed that child capacity to elaborate emotional experiences partially mediated the link between maternal capacity to elaborate emotional content and child security of attachment. Our results emphasize the importance of mother-child conversational exchanges for the development of attachment in preschool children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Abstract word deficits in aphasia: Evidence from semantic priming.

J.G. and D.E. are nonfluent aphasic patients who appear to have selective problems with abstract words on a variety of standard tests. Such a pattern would normally be interpreted as indicating a central semantic deficit for abstract words. The authors show that this is not the case by means of a semantic priming task that tests for implicit knowledge of the meanings of abstract and concrete words. Spoken word pairs that were either abstract or concrete synonyms (e.g., street-road or luck-chance) were presented; both Ss showed priming for the abstract and concrete pairs. The researchers followed up by asking the Ss to produce definitions to spoken abstract and concrete words; these definitions were also normal. The priming and definition data suggest that the semantic representations of abstract words in these Ss were relatively unimpaired. The researchers found that the Ss have problems only with spoken abstract words in just those tasks where normal controls also have difficulty. In contrast, they clearly have deficits in reading abstract words aloud, which may be due to problems with output phonology. Implications of these data for claims concerning hemispheric differences in the representation of abstract and concrete words are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modulating the RAGE-Induced Inflammatory Response: Peptoids as RAGE Antagonists

While the primary pathology of Alzheimer's disease (AD) is defined by brain deposition of amyloid-β (Aβ) plaques and tau neurofibrillary tangles, chronic inflammation has emerged as an important factor in AD etiology. Upregulated cell surface expression of the receptor for advanced glycation end-products (RAGE), a key receptor of innate immune response, is reported in AD. In parallel, RAGE ligands, including Aβ aggregates, HMGB1, and S100B, are elevated in AD brain. Activation of RAGE by these ligands triggers release of inflammatory cytokines and upregulates cell surface RAGE. Despite such observation, there are currently no therapeutics that target RAGE for treatment of AD-associated neuroinflammation. Peptoids, a novel class of potential AD therapeutics, display low toxicity, facile blood-brain barrier permeability, and resistance to proteolytic degradation. In the current study, peptoids were designed to mimic Aβ, a ligand that binds the V-domain of RAGE, and curtail RAGE inflammatory activation. We reveal the nanomolar binding capability of peptoids JPT1 and JPT1a to RAGE and demonstrate their ability to attenuate lipopolysaccharide-induced pro-inflammatory cytokine production as well as upregulation of RAGE cell surface expression. These results support RAGE antagonist peptoid-based mimics as a prospective therapeutic strategy to counter neuroinflammation in AD and other neurodegenerative diseases.     

Neural network-based optical flow versus traditional optical flow techniques with thermal aerial imaging in real-world settings

The study explores the feasibility of optical flow-based neural network from real-world thermal aerial imagery. While traditional optical flow techniques have shown adequate performance, sparse techniques do not work well during cold-soaked low-contrast conditions, and dense algorithms are more accurate in low-contrast conditions but suffer from the aperture problem in some scenes. On the other hand, optical flow from convolutional neural networks has demonstrated good performance with strong generalization from several synthetic public data set benchmarks. Ground truth was generated from real-world thermal data estimated with traditional dense optical flow techniques. The state-of-the-art Recurrent All-Pairs Field Transform for the Optical Flow model was trained with both color synthetic data and the captured real-world thermal data across various thermal contrast conditions. The results showed strong performance of the deep-learning network against established sparse and dense optical flow techniques in various environments and weather conditions, at the cost of higher computational demand.     

(+)-Catechin Attenuates Multiple Atherosclerosis-Associated Processes In Vitro,Modulates Disease-Associated Risk Factors in C57BL/6J Mice and Reduces Atherogenesis in LDL Receptor Deficient Mice by Inhibiting Inflammation and Increasing Markers of Plaque Stability

Scope

A prospective study of 34492 participants shows an inverse association between (+)-catechin intake and coronary heart disease. The effects of (+)-catechin on atherosclerosis and associated risk factors are poorly understood and are investigated.

Methods and results

(+)-Catechin attenuates reactive oxygen species production in human macrophages, endothelial cells and vascular smooth muscle cells, chemokine-driven monocytic migration, and proliferation of human macrophages and their expression of several pro-atherogenic genes. (+)-Catechin also improves oxidized LDL-mediated mitochondrial membrane depolarization in endothelial cells and attenuates growth factor-induced smooth muscle cell migration. In C57BL/6J mice fed high fat diet (HFD) for 3 weeks, (+)-catechin attenuates plasma levels of triacylglycerol and interleukin (IL)-1β and IL-2, produces anti-atherogenic changes in liver gene expression, and reduces levels of white blood cells, myeloid-derived suppressor cells, Lin⁻ Sca⁺ c-Kit⁺ cells, and common lymphoid progenitor cells within the bone marrow. In LDL receptor deficient mice fed HFD for 12 weeks, (+)-catechin attenuates atherosclerotic plaque burden and inflammation with reduced macrophage content and increased markers of plaque stability; smooth muscle cell and collagen content.

Conclusion

This study provides novel, detailed insights into the cardio-protective actions of (+)-catechin together with underlying molecular mechanisms and supports further assessments of its beneficial effects in human trials.