37 research outputs found
THE INCIDENCE AND NATURE OF NON-CONTACT INJURIES IN U.S. WOMEN’S RUGBY-7S
The aim of this study was to prospectively determine non-contact injury incidence and mechanisms among U.S. amateur women’s Rugby-7s. Non-contact injuries occurred frequently among the U.S. women population (26.5/1000ph; 29% of all injuries; n=167). The incidence of non-contact injuries occurred at similar rates among backs (58%, 23.9/1000ph, CI:19.1-29.6) and forwards (42%, 19.3/1000ph, CI:14.4-25.3; RR:1.04, p=0.816). Non-contact injuries resulted in 58.4 mean days absence from play. This study demonstrates a greater proportion of match injuries among U.S. amateur women Rugby-7 participants were related to non-contact mechanism when compared to International women participants. Therefore, U.S. women Rugby-7 players would benefit from prevention programs to minimize non-contact injury risks
Agency culture, constitutional provisions and entrepreneurship: a cross-country analysis
Substantial and systematic cross-country variation in entrepreneurship rates has been found in vari- ous studies. We attempt to explain such differences focusing on the interaction between institutional factors and population psychological characteristics. Constitutional provisions supporting economic freedom are our measure of the institutional context, whereas we proxy psychological characteristics with a country’s endowment of agency culture. We apply an IV-GMM treatment to deal with endoge- 20 neity to a data set comprising 86 countries over the period 2004–2013, and we control for de facto vari- ables and other factors that are likely to influence entrepreneurship. Our results demonstrate that agency culture is indeed an important predictor of entrepreneurship and that this effect is moderated
by constitutional provisions supporting economic freedom. In particular, the impact of agency culture
on entrepreneurship becomes stronger as a country expands the constitutional protection of eco- 25 nomic rights
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Building a multi-scaled geospatial temporal ecology database from disparate data sources: fostering open science and data reuse
Although there are considerable site-based data for individual or groups of ecosystems, these datasets are widely scattered, have different data formats and conventions, and often have limited accessibility. At the broader scale, national datasets exist for a large number of geospatial features of land, water, and air that are needed to fully understand variation among these ecosystems. However, such datasets originate from different sources and have different spatial and temporal resolutions. By taking an open-science perspective and by combining site-based ecosystem datasets and national geospatial datasets, science gains the ability to ask important research questions related to grand environmental challenges that operate at broad scales. Documentation of such complicated database integration efforts, through peer-reviewed papers, is recommended to foster reproducibility and future use of the integrated database. Here, we describe the major steps, challenges, and considerations in building an integrated database of lake ecosystems, called LAGOS (LAke multi-scaled GeOSpatial and temporal database), that was developed at the sub-continental study extent of 17 US states (1,800,000 km² ). LAGOS includes two modules: LAGOS[subscript]GEO , with geospatial data on every lake with surface area larger than 4 ha in the study extent (~50,000 lakes), including climate, atmospheric deposition, land use/cover, hydrology, geology, and topography measured across a range of spatial and temporal extents; and LAGOS[subscript]LIMNO , with lake water quality data compiled from ~100 individual datasets for a subset of lakes in the study extent (~10,000 lakes). Procedures for the integration of datasets included: creating a flexible database design; authoring and integrating metadata; documenting data provenance; quantifying spatial measures of geographic data; quality-controlling integrated and derived data; and extensively documenting the database. Our procedures make a large, complex, and integrated database reproducible and extensible, allowing users to ask new research questions with the existing database or through the addition of new data. The largest challenge of this task was the heterogeneity of the data, formats, and metadata. Many steps of data integration need manual input from experts in diverse fields, requiring close collaboration.Keywords: LAGOS, Integrated database, Data harmonization, Database
Ecoinformatics, Macrosystems ecology, Landscape limnology, Water qualityKeywords: LAGOS, Integrated database, Ecoinformatics, Data harmonization, Water quality, Data sharing, Landscape limnology, Macrosystems ecology, Database documentation, Data reus
Optimizing database-backed applications with query synthesis
Object-relational mapping libraries are a popular way for applications to interact with databases because they provide transparent access to the database using the same language as the application. Unfortunately, using such frameworks often leads to poor performance, as modularity concerns encourage developers to implement relational operations in application code. Such application code does not take advantage of the optimized relational implementations that database systems provide, such as efficient implementations of joins or push down of selection predicates. In this paper we present QBS, a system that automatically transforms fragments of application logic into SQL queries. QBS differs from traditional compiler optimizations as it relies on synthesis technology to generate invariants and postconditions for a code fragment. The postconditions and invariants are expressed using a new theory of ordered relations that allows us to reason precisely about both the contents and order of the records produced complex code fragments that compute joins and aggregates. The theory is close in expressiveness to SQL, so the synthesized postconditions can be readily translated to SQL queries. Using 75 code fragments automatically extracted from over 120k lines of open-source code written using the Java Hibernate ORM, we demonstrate that our approach can convert a variety of imperative constructs into relational specifications and significantly improve application performance asymptotically by orders of magnitude.Intel CorporationNational Science Foundation (U.S.) (Grant 1065219)National Science Foundation (U.S.) (Grant 1139056