Hidden Toxins in Everyday Cosmetic

Lead, nickel, and cadmium are among the most common heavy metals found in cosmetics today. Heavy metal exposure and toxins in face powders and shampoos can cause damage to skin and hair follicles. I tested multiple lipsticks, shampoos, and face powders for lead, nickel and cadmium by ICP-OES and compare the results to FDA regulations. I also measured the Raman spectra of these samples and sorted them using principal component analysis (PCA) to identify if those samples containing heavy metals could be classified by Raman

Effects of Formulated Feed on water Quality in Fingerling Waleye Production Ponds

Six 0.04-ha plastic-lined ponds were used at the Iowa Department of Natural Resources’ Rathbun Fish Culture and Research Facility to evaluate the use of supplemental fish food on walleye (Sander vitreus) fingerling growth and survival, and on the benthic invertebrate community. Walleye were stocked 3-4 days post hatch on 2 May 2003, and harvested 5-6 June 2003. Organic fertilizer (alfalfa pellets, 112kg/ha/week) was used to increase primary production and inorganic fertilizers were added periodically to maintain a target nutrient ratio of 7:1 nitratenitrogen to total phosphorus (NO3-N: TP). Additional nutrients in the form of Lansy CW fish feed were added to three of the six ponds. The objective of this project was to determine the effect of a commercial fish diet on water quality. At the end of the culture season, there were significant differences between water chemistry parameters in the ponds; the feed treatments had higher levels of nitrogenous compounds and total phosphorus

Models of dynamic extraction of lipid tethers from cell membranes

When a ligand that is bound to an integral membrane receptor is pulled, the membrane and the underlying cytoskeleton can deform before either the membrane delaminates from the cytoskeleton or the ligand detaches from the receptor. If the membrane delaminates from the cytoskeleton, it may be further extruded and form a membrane tether. We develop a phenomenological model for this processes by assuming that deformations obey Hooke's law up to a critical force at which the cell membrane locally detaches from the cytoskeleton and a membrane tether forms. We compute the probability of tether formation and show that they can be extruded only within an intermediate range of force loading rates and pulling velocities. The mean tether length that arises at the moment of ligand detachment is computed as are the force loading rates and pulling velocities that yield the longest tethers.Comment: 16 pages, 7 figure

Dissociation of Response and Feedback Negativity in Schizophrenia: Electrophysiological and Computational Evidence for a Deficit in the Representation of Value

Contrasting theories of schizophrenia propose that the disorder is characterized by a deficit in phasic changes in dopamine activity in response to ongoing events or, alternatively, by a weakness in the representation of the value of responses. Schizophrenia patients have reliably reduced brain activity following incorrect responses but other research suggests that they may have intact feedback-related potentials, indicating that the impairment may be specifically response-related. We used event-related brain potentials and computational modeling to examine this issue by comparing the neural response to outcomes with the neural response to behaviors that predict outcomes in patients with schizophrenia and psychiatrically healthy comparison subjects. We recorded feedback-related activity in a passive gambling task and a time estimation task and error-related activity in a flanker task. Patients’ brain activity following an erroneous response was reduced compared to comparison subjects but feedback-related activity did not differ between groups. To test hypotheses about the possible causes of this pattern of results, we used computational modeling of the electrophysiological data to simulate the effects of an overall reduction in patients’ sensitivity to feedback, selective insensitivity to positive or negative feedback, reduced learning rate, and a decreased representation of the value of the response given the stimulus on each trial. The results of the computational modeling suggest that schizophrenia patients exhibit weakened representation of response values, possibly due to failure of the basal ganglia to strongly associate stimuli with appropriate response alternatives

Inviting Participation through IoT: Experiments and Performances in Public Spaces

This paper proposes a workshop on the Internet of Things (IoT) for participation in public life. We will bring together artists, designers, practitioners, and academics interested in site-specific projects involving lighting and other ambient technologies intended to serve community interests such as representation and safety. The authors share their current inquiry on stairwells as an example. Discussion of this project and others will help us locate, trace, and develop networked environments.

Stroke survivors’ perceptions of their sedentary behaviours three months after stroke

Purpose:Sedentary behaviour is any waking behaviour in sitting, lying or reclining postures with low energy expenditure. High sedentary behaviour levels, common after stroke, are associated with poor health and higher levels of mobility disability. The aim of this study was to undertake a behavioural diagnosis of sedentary behaviour in the early phase after stroke to inform interventions that may reduce sedentary behaviour and associated disability. Methods and materials:Independently mobile stroke survivors were interviewed three months after stroke. The topic guide was informed by the central layer of the Behaviour Change Wheel to explore three components: capability, opportunity and motivation. This model recognises that behaviour is the consequence of an interacting system of these components. Interviews were transcribed verbatim and analysed using The Framework Method. Results:Thirty one people were interviewed (66.7 years; 16 male). The perception of diminished capability to reduce sedentary behaviour due to physical tiredness/fatigue, and pain/discomfort acting as both a motivator and inhibitor to movement, were discussed. Environmental barriers and the importance of social interaction were highlighted. Perceived motivation to reduce sedentary behaviour was influenced by enjoyment of sedentary behaviours, fear of falling and habitual nature of sedentary behaviours. Conclusions:This information will inform evidence-based sedentary behaviour interventions after stroke