NSV 13983: A New Dwarf Nova in the Period Gap

Aims. NSV 13983 is catalogued as a dwarf nova based on a reported outburst from 2005. The system has not yet been studied spectroscopically. We attempt to confirm its nature as a dwarf nova and determine its orbital period. Methods. We derive the orbital period by using time-resolved spectroscopic data to measure radial velocities. Results. The average spectrum shows evidence that the system is a dwarf nova in quiescence. The radial velocity curves derived from measurements of the spectral lines H\alpha and H\beta, show a clear modulation with a period of 2.76 h. This places NSV 13983 below the upper edge of the gap in the period distribution of cataclysmic variables, implying that it is the 14th dwarf nova in the gap.Comment: 3 pages, 4 figures, 1 tables, accepted by A&

Drugs, Crime, Space, and Time: A Spatiotemporal Examination of Drug Activity and Crime Rates

To take stock of the “neighborhood effects” of drug activity, we combined theoretical insights from the drugs and crime and communities and place literatures in examining the longitudinal relationship between drug activity and crime rates at more spatially and temporally precise levels of granularity, with blocks as the spatial units and months as the temporal units. We found that drug activity on a block one month “pushes” assaultive violence into surrounding blocks the next month. Integrating perspectives form social disorganization theory with Zimring and Hawkins’ (1997) contingency causation theory, we also found that the economic resources and residential stability of the “the larger social environment”—that is, the surrounding quarter-mile egohood area—moderate drug activity’s block-level relationship to crime. These results suggest that drug activity increases assaultive violence and serious acquisitive crime rates on structurally advantaged blocks, producing a significant ecological niche redefinition for such blocks relative to others in Miami-Dade County, Florida

Text-based Semantic Annotation Service for Multimedia Content in the Esperonto project

Within the Esperonto project, an integration of NLP, ontologies and other knowledge bases, is being performed with the goal to implement a semantic annotation service that upgrades the actual Web towards the emerging Semantic Web. Research is being currently conducted on how to apply the Esperonto semantic annotation service to text material associated with still images in web pages. In doing so, the project will allow for semantic querying of still images in the web, but also (automatically) create a large set of text-based semantic annotations of still images, which can be used by the Multimedia community in order to support the task of content indexing of image material, possibly combining the Esperonto type of annotations with the annotations resulting from image analysis

The effects of lengthening the school day on female labor supply: Evidence from a quasi-experiment in Chile

In 1996, the Chilean government approved the extension of the school day, increasing the amount of time that students spend at school by 30%. Using data from the Chilean socio- economic household survey and administrative data from the Ministry of Education for 1990- 2006, we exploit the quasi-experimental nature of the reform’s implementation by time and region in order to identify the causal impact of the program on labor participation, employment and hours worked for women between 20 and 65 years old. The identification strategy relies on a fixed effect model of repeated cross-section. The results show a positive and significant effect on labor participation and female employment in all age groups and a negative and statistically significant effect on the number of hours worked. The main conclusion of this study is that the implicit childcare subsidy induced by the program had a positive and significant impact on the labor supply of women in Chile.Female labor supply; childcare; fertility; labor supply; Chile.