An Econometric Model of High School Graduation Rates in Oregon

This study aims to analyze potential factors causing low high school graduation rates in the state of Oregon. We developed an econometric model measuring six independent variables: violent crime rates; income per family, the percentage of the population that is Hispanic, the percentage of family households with only one parent, alcohol use in adults, and teen pregnancy. Our dependent variable was measured as the percentage of the population between 18 and 24 without a high school diploma. From our results we found two of our variables to be economically significant: family structure and alcohol. However, the coefficient for alcohol suggested that higher rates of binge drinking in adults lead to higher graduation rates, which contradicts expectations. This outcome is addressed within the paper. Overall, this study suggests that family structure has the largest and clearest impact on graduation rates in Oregon, out of the variables included in our model

Poverty, Opportunity, and Well-Being in the United States

Economic opportunity varies dramatically across the United States. In this study the Opportunity to Flourish Index (OFI) is created to determine the level of opportunity United States cities afford those at the bottom of the income distribution. Indicators within the index measure disposable income, access to financial services, diet, educational attainment, unemployment, physical well-being, and family structure. The OFI’s relationship with standard measures of economic growth and economic mobility is also evaluated. The OFI is not correlated with measures of income and population growth, suggesting, that in the short-run growth and opportunity are not necessarily complementary. The OFI is strongly correlated with intergenerational economic mobility. Individuals that live in cities which have higher levels of opportunity are more likely to have children that move up the income distribution. The OFI provides stakeholders in poverty alleviation a means to evaluate and promote equality of opportunity in United States cities

Safe Robotic Grasping: Minimum Impact-Force Grasp Selection

This paper addresses the problem of selecting from a choice of possible grasps, so that impact forces will be minimised if a collision occurs while the robot is moving the grasped object along a post-grasp trajectory. Such considerations are important for safety in human-robot interaction, where even a certified "human-safe" (e.g. compliant) arm may become hazardous once it grasps and begins moving an object, which may have significant mass, sharp edges or other dangers. Additionally, minimising collision forces is critical to preserving the longevity of robots which operate in uncertain and hazardous environments, e.g. robots deployed for nuclear decommissioning, where removing a damaged robot from a contaminated zone for repairs may be extremely difficult and costly. Also, unwanted collisions between a robot and critical infrastructure (e.g. pipework) in such high-consequence environments can be disastrous. In this paper, we investigate how the safety of the post-grasp motion can be considered during the pre-grasp approach phase, so that the selected grasp is optimal in terms applying minimum impact forces if a collision occurs during a desired post-grasp manipulation. We build on the methods of augmented robot-object dynamics models and "effective mass" and propose a method for combining these concepts with modern grasp and trajectory planners, to enable the robot to achieve a grasp which maximises the safety of the post-grasp trajectory, by minimising potential collision forces. We demonstrate the effectiveness of our approach through several experiments with both simulated and real robots.Comment: To be appeared in IEEE/RAS IROS 201

Abnormal returns on CEFs in pre- and post-credit-crunch periods

Compared to previous research, present work extends existing literature by considering if market performance, in Athens Stock Exchange, alternates the mean-reverting properties of Closed-end Funds’ discount and as a result affects potential realization of abnormal returns. Employing cointegration analysis, reported results indicate that, examining an equally weighted portfolio of funds, when market performance characterized as moderate, there is evidence suggesting market inefficiency while; during the recent turmoil period due to the credit crisis evidences do not indicate potential realization of abnormal returns. However, individual data examination gives mixed results.peer-reviewe

Plasma Membrane Polarity and Compartmentalization Are Established before Cellularization in the Fly Embryo

SummaryPatterning in the Drosophila embryo requires local activation and dynamics of proteins in the plasma membrane (PM). We used in vivo fluorescence imaging to characterize the organization and diffusional properties of the PM in the early embryonic syncytium. Before cellularization, the PM is polarized into discrete domains having epithelial-like characteristics. One domain resides above individual nuclei and has apical-like characteristics, while the other domain is lateral to nuclei and contains markers associated with basolateral membranes and junctions. Pulse-chase photoconversion experiments show that molecules can diffuse within each domain but do not exchange between PM regions above adjacent nuclei. Drug-induced F-actin depolymerization disrupted both the apicobasal-like polarity and the diffusion barriers within the syncytial PM. These events correlated with perturbations in the spatial pattern of dorsoventral Toll signaling. We propose that epithelial-like properties and an intact F-actin network compartmentalize the PM and shape morphogen gradients in the syncytial embryo

Προστασία επαφών ηλεκτρονόμου με varistor

Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) “Παραγωγή και Διαχείρηση Ενέργειας

Purification of recombinant human and Drosophila septin hexamers for TIRF assays of actin-septin filament assembly

International audienceSeptins are guanine nucleotide-binding proteins that are conserved from fungi to humans. Septins assemble into heterooligomeric complexes and higher-order structures with key roles in various cellular functions including cell migration and division. The mechanisms by which septins assemble and interact with other cytoskeletal elements like actin remain elusive. A powerful approach to address this question is by cell-free reconstitution of pu- rified cytoskeletal proteins combined with fluorescence microscopy. Here, we describe procedures for the purification of recombinant Drosophila and human septin hexamers from Escherichia coli and reconstitution of actin-septin coassembly. These procedures can be used to compare assembly of Drosophila and human septins and their coassembly with the actin cytoskeleton by total internal reflection fluorescence microscopy