Understanding Crowd-Powered Search Groups: A Social Network Perspective

Background: Crowd-powered search is a new form of search and problem solving scheme that involves collaboration among a potentially large number of voluntary Web users. Human flesh search (HFS), a particular form of crowd-powered search originated in China, has seen tremendous growth since its inception in 2001. HFS presents a valuable test-bed for scientists to validate existing and new theories in social computing, sociology, behavioral sciences, and so forth. Methodology: In this research, we construct an aggregated HFS group, consisting of the participants and their relationships in a comprehensive set of identified HFS episodes. We study the topological properties and the evolution of the aggregated network and different sub-groups in the network. We also identify the key HFS participants according to a variety of measures. Conclusions: We found that, as compared with other online social networks, HFS participant network shares the power-law degree distribution and small-world property, but with a looser and more distributed organizational structure, leading to the diversity, decentralization, and independence of HFS participants. In addition, the HFS group has been becoming increasingly decentralized. The comparisons of different HFS sub-groups reveal that HFS participants collaborated more often when they conducted the searches in local platforms or the searches requiring a certain level of professional knowledge background. On the contrary, HFS participants did not collaborate much when they performed the search tas

WCT_introgression_data

File contains SNP data for all field samples included in the paper. Additionally, information in table S1 has been included allowing SNPs to be identified by both sequence and source

qPCR detection of Sturgeon chub (Macrhybopsis gelida) DNA in environmental samples.

The Sturgeon chub (Macrhybopsis gelida) is a cyprinid fish native to the Missouri and Mississippi River basins of the U.S. Suspected long-term declines in the size of its distribution have prompted a review of its conservation status by the U.S. Fish and Wildlife Service, a process which depends on reliable methods to delineate the distribution and status of extant populations. To facilitate monitoring of Sturgeon chub populations, we developed a quantitative PCR assay to detect Sturgeon chub DNA in environmental samples. The assay consistently detected Sturgeon chub DNA in concentrations as low as 2 copies per reaction, and did not amplify DNA from non-target fish species that are sympatric in the upper Missouri River basin. Field tests of this assay with environmental samples successfully detected Sturgeon chub from sites known to be occupied. This assay offers an extremely sensitive methodology that can be applied to determine the range of Sturgeon chub, regardless of variation in habitat characteristics

Medical tourism: a cost or benefit to the NHS?

'Medical Tourism' - the phenomenon of people travelling abroad to access medical treatment - has received increasing attention in academic and popular media. This paper reports findings from a study examining effect of inbound and outbound medical tourism on the UK NHS, by estimating volume of medical tourism and associated costs and benefits. A mixed methods study it includes analysis of the UK International Passenger Survey (IPS); interviews with 77 returning UK medical tourists, 63 policymakers, NHS managers and medical tourism industry actors policymakers, and a review of published literature. These informed costing of three types of treatments for which patients commonly travel abroad: fertility treatment, cosmetic and bariatric surgery. Costing of inbound tourism relied on data obtained through 28 Freedom-of-Information requests to NHS Foundation Trusts. Findings demonstrate that contrary to some popular media reports, far from being a net importer of patients, the UK is now a clear net exporter of medical travellers. In 2010, an estimated 63,000 UK residents travelled for treatment, while around 52,000 patients sought treatment in the UK. Inbound medical tourists treated as private patients within NHS facilities may be especially profitable when compared to UK private patients, yielding close to a quarter of revenue from only 7% of volume in the data examined. Costs arise where patients travel abroad and return with complications. Analysis also indicates possible savings especially in future health care and social costs averted. These are likely to be specific to procedures and conditions treated. UK medical tourism is a growing phenomenon that presents risks and opportunities to the NHS. To fully understand its implications and guide policy on issues such as NHS global activities and patient safety will require investment in further research and monitoring. Results point to likely impact of medical tourism in other universal public health systems

Data from: Climate, demography, and zoogeography predict introgression thresholds in Salmonid hybrid zones in Rocky Mountain streams

Among the many threats posed by invasions of nonnative species is introgressive hybridization, which can lead to the genomic extinction of native taxa. This phenomenon is regarded as common and perhaps inevitable among native cutthroat trout and introduced rainbow trout in western North America, despite that these taxa naturally co-occur in some locations. We conducted a synthetic analysis of 13,315 genotyped fish from 558 sites by building logistic regression models using data from geospatial stream databases and from 12 published studies of hybridization to assess whether environmental covariates could explain levels of introgression between westslope cutthroat trout and rainbow trout in the U.S. northern Rocky Mountains. A consensus model performed well (AUC, 0.78–0.86; classification success, 72–82%; 10-fold cross validation, 70–82%) and predicted that rainbow trout introgression was significantly associated with warmer water temperatures, larger streams, proximity to warmer habitats and to recent sources of rainbow trout propagules, presence within the historical range of rainbow trout, and locations further east. Assuming that water temperatures will continue to rise in response to climate change and that levels of introgression outside the historical range of rainbow trout will equilibrate with those inside that range, we applied six scenarios across a 55,234-km stream network that forecast 9.5–74.7% declines in the amount of habitat occupied by westslope cutthroat trout populations of conservation value, but not the wholesale loss of such populations. We conclude that introgression between these taxa is predictably related to environmental conditions, many of which can be manipulated to foster largely genetically intact populations of westslope cutthroat trout and help managers prioritize conservation activities