The benefit of symbols: monkeys show linear, human-like, accuracy when using symbols to represent scalar value

When humans and animals estimate numbers of items, their error rate is proportional to the number. To date, however, only humans show the capacity to represent large numbers symbolically, which endows them with increased precision, especially for large numbers, and with tools for manipulating numbers. This ability depends critically on our capacity to acquire and represent explicit symbols. Here we show that when rhesus monkeys are trained to use an explicit symbol system, they too show more precise, and linear, scaling than they do using a one-to-one corresponding numerosity representation. We also found that when taught two different types of representations for reward amount, the monkeys systematically undervalued the less precise representation. The results indicate that monkeys, like humans, can learn alternative mechanisms for representing a single value scale and that performance variability and relative value depend on the distinguishability of each representation

Normal Leptin Expression, Lower Adipogenic Ability, Decreased Leptin Receptor and Hyposensitivity to Leptin in Adolescent Idiopathic Scoliosis

Leptin has been suggested to play a role in the etiology of Adolescent Idiopathic Scoliosis (AIS), however, the leptin levels in AIS girls are still a discrepancy, and no in vitro study of leptin in AIS is reported. We took a series of case-control studies, trying to understand whether Leptin gene polymorphisms are involved in the etiology of the AIS or the change in leptin level is a secondary event, to assess the level of leptin receptor, and to evaluate the differences of response to leptin between AIS cases and controls. We screened all exons of Leptin gene in 45 cases and 45 controls and selected six tag SNPs to cover all the observed variations. Association analysis in 446 AIS patients and 550 healthy controls showed no association between the polymorphisms of Leptin gene and susceptibility/severity to AIS. Moreover, adipogenesis assay of bone mesenchymal stem cells (MSCs) suggested that the adipogenic ability of MSCs from AIS girls was lower than controls. After adjusting the differentiation rate, expressions of leptin and leptin receptor were similar between two groups. Meanwhile, osteogenesis assay of MSC showed the leptin level was similar after adjusting the differentiation rate, but the leptin receptor level was decreased in induced AIS osteoblasts. Immunocytochemistry and western blot analysis showed less leptin receptors expressed in AIS group. Furthermore, factorial designed studies with adipogenesis and osteogenesis revealed that the MSCs from patients have no response to leptin treatment. Our results suggested that Leptin gene variations are not associated with AIS and low serum leptin probably is a secondary outcome which may be related to the low capability of adipogenesis in AIS. The decreased leptin receptor levels may lead to the hyposensitivity to leptin. These findings implied that abnormal peripheral leptin signaling plays an important role in the pathological mechanism of AIS

Using fMRI to distinguish components of the multiple object tracking task.

Multiple object tracking (MOT) has proven to be a powerful technique for studying sustained selective attention. However, surprisingly little is known about its underlying neural mechanisms. Previous fMRI investigations have identified several brain areas thought to be involved in MOT, but there were disagreements between the studies, none distinguished between the act of tracking targets and the act of attending targets, and none attempted to determine which of these brain areas interact with each other. Here we address these three issues. First, using more observers and a random effects analysis, we show that some of the previously identified areas may not play a specific role in MOT. Second, we show that the frontal eye fields (FEF), the anterior intraparietal sulcus (AIPS), the superior parietal lobule (SPL), the posterior intraparietal sulcus (PIPS) and the human motion area (MT+) are differentially activated by the act of tracking, as distinguished from the act of attention. Finally, by using an algorithm modified from the computer science literature, we were able to map the interactions between these brain areas

University Maker Spaces: Discovery, Optimization and Measurement of Impacts

Presented at 2015 ASEE Annual Conference and Exposition, Seattle, WA.It is essential that modern engineers not only master engineering science and analysis, but they must also learn to drive the next generation of design, creation, and innovation. In parallel to the success of community maker spaces outside of academic settings, many universities are moving beyond traditional machine shops and building multi-disciplinary maker space design centers. This project seeks to understand and use these new environments to achieve elusive aims in engineering education such as improving at-risk student retention, fostering diverse learning environments, and promoting multi-disciplinary teams. We will also investigate the potential of maker spaces to positively influence females and minorities and thereby broaden participation in engineering. Impact will be measured through engineering design self-efficacy; retention in the engineering major; and idea generation ability. Impacts will be measured at two levels. The first level of the project will use a randomly assigned experimental design to assess the impact of early maker space engagement on females and minorities through longitudinal measurements. In the second level, we compare segment snapshots and longitudinal measurements between extensive maker space users and those with minimal exposure. We will also identify best-practice approaches and guidelines for designing maker spaces, through discussions and interviews with leaders of maker spaces from educational institution around the country

Acclimation to low water potential determines changes in membrane fatty acid composition and fluidity in potato cells

Potato (Solanum tuberosum) cells were gradually acclimated to grow at low water potential created by addition of increasing concentrations of polyethylene glycol (PEG) 8000 to the nutrient medium. While growth of cells abruptly transferred into a medium containing 20% PEG was dramatically inhibited, under the same stress intensity gradually acclimated cells were able to sustain active growth similarly to control unstressed cells. Gradual acclimation allowed the maintenance of normal cellular and subcellular membrane structure at an osmotic potential of -2.3 MPa, which caused extended membrane disruption when applied to non-acclimated control cells. Analysis of fatty acids (FAs) from control and acclimated cells revealed that the mol percentage composition of the major extra-plastidial phospholipids (PLs) was basically unchanged, but both phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were more saturated in acclimated cells. The decrease in unsaturation occurred primarily at the expense of linoleic acid (18:2) in the PE fraction. A significant increase in the percentage content of palmitic acid (16:0) of the PE fraction was also detected in acclimated cells. Membrane microviscosity, as determined by diphenyl-hexatriene (DPH) labelling, was higher in PEG-acclimated cells, as expected from the lower degree of unsaturation of membrane FAs found in acclimated cells. The steady-state transcript levels of a Δ9-stearoyl-acyl carrier protein-desaturase and a Δ12-oleoyl-desaturase gene decreased in acclimated cells, suggesting that the variation in the level of FA unsaturation was at least partially associated with down-regulation of the expression of these genes