Environmental news: coverage of the Earth Summit by Brazilian newspapers

This article examines how two important Brazilian newspapers (Floha de S. Paulo and O Globo) covered the UN Conference on Environment and Development (UNCED) or Earth Summit. The analysis will also determine the characteristics of the environmental media and its significance when it comes to coverage of environmental issues. This article provides historical background information on the environmental media in the US and in Brazil, contextual information on the Earth Summit, a content analysis of stories about UNCED published by the two Brazilian newspapers. Overall, 649 news items were used to determine the type of sources used, as well as the kind of issues covered. The analysis showed that government officials were the most frequently cited sources, while environmentalists and scientists were all but ignored as news sources. The analysis also indicated that economic issues were surprisingly prominent in the coverage. These results are compatible with the previous studies done in several countries and indicate that environmental media are still extremely reliant on "official" voices. The finding also highlight the fact that the range of issues covered by the environmental media largely reflects the perceived public agenda.     

A medical journal's beta site: experimentation at NEJM

When continuous development becomes the norm on the social web, finding a way to put forward new development ideas to your audience and get their feedback at an early stage is the natural result. This article discusses how one major medical journal created a ‘beta’ site to support new online development and gather user feedback, speeding development initiatives and creating intrinsic value in the experimental environment. The goals of the site, organization of the teams, and practical and brand benefits are discussed.     

Efficient reverse k-nearest neighbor estimation

The reverse k-nearest neighbor (RkNN) problem, i.e. finding all objects in a data set the k-nearest neighbors of which include a specified query object, has received increasing attention recently. Many industrial and scientific applications call for solutions of the RkNN problem in arbitrary metric spaces where the data objects are not Euclidean and only a metric distance function is given for specifying object similarity. Usually, these applications need a solution for the generalized problem where the value of k is not known in advance and may change from query to query. In addition, many applications require a fast approximate answer of RkNN-queries. For these scenarios, it is important to generate a fast answer with high recall. In this paper, we propose the first approach for efficient approximative RkNN search in arbitrary metric spaces where the value of k is specified at query time. Our approach uses the advantages of existing metric index structures but proposes to use an approximation of the nearest-neighbor-distances in order to prune the search space. We show that our method scales significantly better than existing non-approximative approaches while producing an approximation of the true query result with a high recall.     

Differences in activation patterns between eccentric and concentric quadriceps contractions.

Previous studies analysing electromyograms (EMGs) from indwelling electrodes have indicated that fast-twitch motor units are selectively recruited for low-intensity eccentric contractions. The aim of this study was to compare the frequency content of surface EMGs from quadriceps muscles during eccentric and concentric contractions at various contraction intensities. Electromyograms were recorded from the rectus femoris, vastus lateralis and vastus medialis muscles of 10 men during isokinetic (1.05 rad x s(-1)) eccentric and concentric knee extension contractions at 25%, 50%, 75% and 100% of maximal voluntary contraction (MVC) for each contraction mode. Additionally, isometric contractions (70 degrees) were performed at each intensity. The mean frequency and root mean square (RMS) of the surface EMG were computed. Mean frequency was higher for eccentric than concentric contractions at 25% (P < 0.01), 50% (P < 0.01) and 75% (P < 0.05) but not at 100% MVC. It increased with increasing contraction intensity for isometric (P < 0.001) and concentric (P < 0.01) contractions but not for eccentric contractions (P = 0.27). The EMG amplitude (RMS) increased with increasing contraction intensity similarly in each contraction mode (P < 0.0001). Higher mean frequencies for eccentric than concentric contractions at submaximal contraction intensities is consistent with more fast-twitch motor units being active during eccentric contractions.     

Journal acquisition—cost effectiveness of models

This paper attempts to compare some of the available models for journal acquisition and indicates their utility in library acquisitions.