Evaluation of Extent and Bioavailability of Chromium Contamination Near an Abandoned Strip Mine

Chromium is a potentially toxic element to plants and animals commonly associated with serpentine and anthropogenic sources. An abandoned Cr strip-mine at US National Guard Camp SLO, CA containing serpentinitic parent material was tested for total and bioavailable Cr in the soil and overlying vegetation via US EPA Methods 3050a (Total Cr) and 1311 (Total Characteristic Leaching Procedure, TCLP) (US EPA, 1995), respectively. The analysis of total and bioavailable Cr was used to assess the risk of nearby surface and groundwater contamination and to evaluate the site’s need for remediation. In addition, trends in soil Cr levels with respect to slope position and sampling transect were identified. Total and most bioavailable Cr concentrations in plants were below the method detection limits (TotalMDL = 0.12 mg L-1; TCLPMDL = 0.04 mg L-1), suggesting the Cr was immobile and not bioavailable. The average total Cr level was 403.5 +/- 177.6 mg kg-1, significantly below the background total Cr level of 829.4 +/- 213.6 mg kg-1. Based on Chromium’s immobility, and its low levels in the site relative to background concentrations, remediation practices were not recommended. No significant trends were observed in total soil Cr levels along any transect or between sampled slope positions. The information gained from this was used by Camp SLO officers to assess the threat of Cr mobility and bioavailability in the soils at this site, as well as in nearby waterways and ground water

Hypergraph model of social tagging networks

The past few years have witnessed the great success of a new family of paradigms, so-called folksonomy, which allows users to freely associate tags to resources and efficiently manage them. In order to uncover the underlying structures and user behaviors in folksonomy, in this paper, we propose an evolutionary hypergrah model to explain the emerging statistical properties. The present model introduces a novel mechanism that one can not only assign tags to resources, but also retrieve resources via collaborative tags. We then compare the model with a real-world dataset: \emph{Del.icio.us}. Indeed, the present model shows considerable agreement with the empirical data in following aspects: power-law hyperdegree distributions, negtive correlation between clustering coefficients and hyperdegrees, and small average distances. Furthermore, the model indicates that most tagging behaviors are motivated by labeling tags to resources, and tags play a significant role in effectively retrieving interesting resources and making acquaintance with congenial friends. The proposed model may shed some light on the in-depth understanding of the structure and function of folksonomy.Comment: 7 pages,7 figures, 32 reference

A Systematic Review and Meta-analysis of the Impact of Mindfulness-Based Interventions on the Well-Being of Healthcare Professionals

Efforts to improve the wellbeing of healthcare professionals include mindfulness-based interventions (MBIs). To understand the value of such initiatives, we conducted a systematic review and meta-analysis of empirical studies pertaining to the use of MBIs with healthcare professionals. Databases were reviewed from the start of records to January 2016 (PROSPERO registration number: CRD42016032899). Eligibility criteria included empirical analyses of wellbeing outcomes acquired in relation to MBIs. Forty-two papers met the eligibility criteria, consisting of a total of 2,101 participants. Studies were examined for two broad classes of wellbeing outcomes: (a) “negative” mental health measures such as anxiety, depression, and stress; (b) “positive” indices of wellbeing, such as life satisfaction, together with outcomes associated with wellbeing, such as emotional intelligence. MBIs were generally associated with positive outcomes in relation to most measures, and mindfulness does appear to improve the wellbeing of healthcare professionals. However, the quality of the studies was inconsistent, so further research is needed, particularly high-quality randomised control trials

PolyLens: A recommender system for groups of users

Abstract. We present PolyLens, a new collaborative filtering recommender system designed to recommend items for groups of users, rather than for individuals. A group recommender is more appropriate and useful for domains in which several people participate in a single activity, as is often the case with movies and restaurants. We present an analysis of the primary design issues for group recommenders, including questions about the nature of groups, the rights of group members, social value functions for groups, and interfaces for displaying group recommendations. We then report on our PolyLens prototype and the lessons we learned from usage logs and surveys from a nine-month trial that included 819 users. We found that users not only valued group recommendations, but were willing to yield some privacy to get the benefits of group recommendations. Users valued an extension to the group recommender system that enabled them to invite non-members to participate, via email

Stabilite et conditionnement de problemes de points-selles et loi des grands nombres en analyse epi/hypographique

SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : T 81284 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Towards emotional well-being by design 17 opportunities for emotion regulation for user-centered healthcare design

Recent attention has been given to the role of emotion regulation in promoting well-being. Although various approaches have been established to design for emotion in design research and HCI, there is only little knowledge on how to support the process of regulating user emotions through design. The paper introduces a framework that delineates 17 emotion regulation strategies based on the theories of emotion regulation. The framework supports an understanding of emotion regulation strategies by enabling designers to compare differences and overlaps of the strategies. The paper describes the framework and its development process along with design examples. Implications and future research steps are discussed