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Between January 2002 and January 2005, water samples were collected at a downstream location of the Sacramento River, CA to quantify mercury concentrations and loads in surface runoff associated with large storm events and re-suspension of river sediments. Mercury concentrations ranged from 3.2 to 14 ng/L and showed a strong correlation to suspended sediment concentrations (SSC). The collection of continuous SSC measurements by U.S. Geological Survey at the study location allowed for extrapolation of the limited mercury data to estimate daily average total mercury loads. For the four years of monitoring in water years (WYs) 2002 - 2005, daily mercury loads ranged from 3 to 4,140 g, while annual mercury loads ranged from approximately 58 kg in WY 2002 to 110 kg in WY 2004. Results from this study have helped refine current estimates of mercury loads to the Bay from the Sacramento-San Joaquin River system. In the context of other significant transport pathways and numerical models, these refined estimates will further assist in understanding the long-term fate of mercury and the recovery of water quality of the Bay.

Background/Objective: Bodily processes have been intimately linked to social-cognitive and affective functions, such as compassion and empathy. Yet, little is known about how awareness of bodily processes influences social awareness and vice versa, especially in nonobservational but experiential investigations. This study investigated the relationship between psychometrically reported body and social awareness (including altruism, empathy, perspective-taking, and compassion) in 90 yoga and yoga-/mediation-naive control participants. In modern postural yoga, advanced practitioners claim both increased compassion and inner focus. Methods: Multiple regression analyses were conducted to predict (1) the level of yoga practice from body awareness and social awareness skills in the yoga group and (2) body awareness from social skills in both groups. Results: Body awareness and compassion were significant positive and independent predictors of yoga expertise. This finding supports practitioners' anecdotal claims but also implies that both functions tap into different aspects of yoga expertise. When body awareness was predicted, altruism emerged as a significant negative predictor in the yoga group (but not control group) as a function of yoga practice. Conclusion: These results might compellingly suggest that, despite high compassion, heightened bodily self-awareness might increase a self-centred perspective and limit altruistic acts in advanced yoga practitioners.

Perception of the visual vertical is strongly based on our ability to match visual inflow with vestibular, proprioceptive, tactile, and even visceral information that contributes to maintaining an internal representation of the vertical. An important cortical region implicated in multisensory integration is the right temporoparietal junction (rTPJ), which also is involved in higher order forms of body- and space-related cognition. To test whether this region integrates body-related multisensory information necessary for establishing the subjective visual vertical, we combined a psychophysical task (the rod-and-frame test) with transient inhibition of the rTPJ via continuous theta burst stimulation (cTBS). A Gabor patch visual detection task was used as a control visual task. cTBS of early visual cortex (V1–V3) was used to test whether early visual cortices played any role in verticality estimation. We show that inhibition of rTPJ activity selectively impairs the ability to evaluate the rod's verticality when no contextual visual information, such as a frame surrounding the rod, is provided. Conversely, transient inhibition of V1–V3 selectively disrupts the ability to visually detect Gabor patch orientation. This anatomofunctional dissociation supports the idea that the rTPJ plays a causal role in integrating egocentric sensory information encoded in different reference systems (i.e., vestibular and somatic) to maintain an internal representation of verticality.

none 3 In the rod and frame test (RFT), participants are asked to set a tilted visual linear marker (i.e., a rod), embedded in a square, to the subjective vertical, irrespective of the surrounding frame. People not influenced by the frame tilt are defined as field-independent, while people biased in their rod verticality perception are field-dependent. Performing RFT requires the integration of proprioceptive, vestibular and visual signals with the latter accounting for field-dependency. Studies indicate that motor experts in body-related, balance-improving disciplines tend to be field-independent, i.e., better at verticality perception, suggesting that proprioceptive and vestibular expertise acquired by such exercise may weaken the influence of irrelevant visual signals. What remains unknown is whether the effect of body-related expertise in weighting perceptual information might also be mediated by personality traits, in particular those indexing self-focusing abilities. To explore this issue, we tested field-dependency in a class of body experts, namely yoga practitioners and in non-expert participants. Moreover we explored any link between performance on RFT and self-transcendence (ST), a complex personality construct, which refers to tendency to experience spiritual feelings and ideas. As expected, yoga practitioners (i) were more accurate in assessing the rod’s verticality on the RFT, and (ii) expressed significantly higher ST. Interestingly, the performance in these two tests was negatively correlated. More specifically, when asked to provide verticality judgments, highly self-transcendent yoga practitioners were significantly less influenced by a misleading visual context. Our results suggest that being highly self-transcendent may enable yoga practitioners to optimize verticality judgment tasks by relying more on internal (vestibular and proprioceptive) signals coming from their own body, rather than on exteroceptive, visual cues. Fiori, Francesca; David, Nicole; Aglioti, Salvatore M. Fiori, Francesca; David, Nicole; Aglioti, Salvatore M.

The rubber hand illusion (RHI) is an enigmatic illusion that creates a feeling of owning an artificial limb. Enthusiasts of this paradigm assert that it operationalizes bodily self-awareness, but there are reasons to doubt such a clear link. Because little is known about other functional contributions to the RHI, including effects of context-dependent visual processing and cognitive control or the ability to resolve intermodal conflict, we carried out two complementary experiments. In the first, we examined the relationships between the RHI and (1) body awareness, as assessed by the Body Perception Questionnaire (BPQ); (2) context-dependent visual processing, as assessed by the rod-and-frame test (RFT); and (3) conflict resolution, as assessed by the Stroop test. We found a significant positive correlation between the RHI-associated proprioceptive drift and context-dependent visual processing on the RFT, but not between the RHI and body awareness on the BPQ. In the second experiment, we examined the RHI in advanced yoga practitioners with an embodied lifestyle and a heightened sense of their own body in space. They succumbed to the illusion just as much as did yoga-naïve control participants, despite significantly greater body awareness on the BPQ. These findings suggest that susceptibility to the RHI and awareness of one's own body are at least partially independent processes. © 2013 Psychonomic Society, Inc.