2,328 research outputs found
Prevalence of the metabolic syndrome in Chinese adolescents
Since national figures on the occurrence of metabolic syndrome among Chinese adolescents are lacking, this study aims to estimate its prevalence and distribution among Chinese youngsters. The 2002 China National Nutrition and Health Survey is a nationally representative cross-sectional study. Applying the criteria for US adolescents, we estimated the prevalence of metabolic syndrome among 2761 adolescents aged 15 to 19 years. The prevalence of metabolic syndrome among Chinese adolescents overall was 3·7% (10% in US adolescents). It was 35·2 %, 23·4% and 2·3% among adolescents who were overweight (BMI 85th percentile and one or two parent(s) with metabolic syndrome, the prevalence was 46·4 %. A total of 96% of overweight adolescents had at least one and 74·1% overweight adolescents had at least two abnormalities of metabolic syndrome. Based on these figures, it is estimated that more than three million Chinese adolescents have metabolic syndrome. Both overweight and metabolic syndrome prevalence among adolescents are still relatively low in China, but the prevalence of metabolic syndrome among Chinese overweight adolescents is similar to those living in the USA
Assisted Tachyonic Inflation
The model of inflation with a single tachyon field generates larger
anisotropy and has difficulties in describing the formation of the Universe .
In this paper we consider a model with multi tachyon fields and study the
assisted inflationary solution. Our results show that this model satisfies the
observation.Comment: 5 pages, no figures, a revised version and reference adde
Sustainable procurement practices in the Brazilian chemical industry context
Sustainable procurement requires an understanding of the full impact of purchase throughout the entire life cycle of the product or service, irrespective of location. The aim is to investigate the adoption of sustainable procurement in some Brazilian chemical companies. Questionnaires were sent to professionals from the Brazilian Chemical Industry Association (ABIQUIM) and from thirtyseven associated companies. The results were used to elaborate empirical illustrations about sustainable procurement practices in the Brazilian chemical industry context. Although the companies did not have a prescriptive supplier selection model that incorporates social-environmental criteria, most companies had more restrictive standards than the legislation and they supported suppliers to improve their social-environmental performance. In addition, that actions related to social and environmental issues occur in policies and documents and are reflected through middle and upper management commitments. It indicates that there are some organizational directions to incorporate social and environmental questions. However, no materialization in actions along the procurement process
Evaluation of land surface models in reproducing satellite derived leaf area index over the high-latitude northern hemisphere. Part II: Earth system models
PublishedJournal ArticleLeaf Area Index (LAI) is a key parameter in the Earth System Models (ESMs) since it strongly affects land-surface boundary conditions and the exchange of matter and energy with the atmosphere. Observations and data products derived from satellite remote sensing are important for the validation and evaluation of ESMs from regional to global scales. Several decades' worth of satellite data products are now available at global scale which represents a unique opportunity to contrast observations against model results. The objective of this study is to assess whether ESMs correctly reproduce the spatial variability of LAI when compared with satellite data and to compare the length of the growing season in the different models with the satellite data. To achieve this goal we analyse outputs from 11 coupled carbon-climate models that are based on the set of new global model simulations planned in support of the IPCC Fifth Assessment Report. We focus on the average LAI and the length of the growing season on Northern Hemisphere over the period 1986-2005. Additionally we compare the results with previous analyses (Part I) of uncoupled land surface models (LSMs) to assess the relative contribution of vegetation and climatic drivers on the correct representation of LAI. Our results show that models tend to overestimate the average values of LAI and have a longer growing season due to the later dormancy. The similarities with the uncoupled models suggest that representing the correct vegetation fraction with the associated parameterizations; is more important in controlling the distribution and value of LAI than the climatic variables. © 2013 by the authors.This work was funded by the European Commission’s 7th Framework Programme under Grant Agreements number 238366 (GREENCYCLESII project) and 282672 (EMBRACE project)
Measuring semantic distance for linked open data-enabled recommender systems
The Linked Open Data (LOD) initiative has been quite successful in terms of publishing and interlinking data on the Web. On top of the huge amount of interconnected data, measuring relatedness between resources and identifying their relatedness could be used for various applications such as LOD-enabled recommender systems. In this paper, we propose various distance measures, on top of the basic concept of Linked Data Semantic Distance (LDSD), for calculating Linked Data semantic distance between resources that can be used in a LOD-enabled recommender system. We evaluated the distance measures in the context of a recommender system that provides the top-N recommendations with baseline methods such as LDSD. Results show that the performance is significantly improved by our proposed distance measures incorporating normalizations that use both of the resources and global appearances of paths in a graph
Exploring dynamics and semantics of user interests for user modeling on Twitter for link recommendations
User modeling for individual users on the Social Web plays
an important role and is a fundamental step for personalization as well as recommendations. Recent studies have
proposed different user modeling strategies considering various dimensions such as temporal dynamics and semantics
of user interests. Although previous work proposed different
user modeling strategies considering the temporal dynamics
of user interests, there is a lack of comparative studies on
those methods and therefore the comparative performance
over each other is unknown. In terms of semantics of user
interests, background knowledge from DBpedia has been
explored to enrich user interest profiles so as to reveal more
information about users. However, it is still unclear to what
extent different types of information from DBpedia contribute
to the enrichment of user interest profiles.
In this paper, we propose user modeling strategies which
use Concept Frequency - Inverse Document Frequency (CF-IDF) as a weighting scheme and incorporate either or both
of the dynamics and semantics of user interests. To this end,
we first provide a comparative study on different user modeling strategies considering the dynamics of user interests in
previous literature to present their comparative performance.
In addition, we investigate different types of information (i.e.,
categories, classes and connected entities via various properties) for entities from DBpedia and the combination of them
for extending user interest profiles. Finally, we build our user
modeling strategies incorporating either or both of the best performing methods in each dimension. Results show that
our strategies outperform two baseline strategies significantly
in the context of link recommendations on Twitter
Inferring user interests in microblogging social networks: a survey
With the growing popularity of microblogging services such as Twitter in recent years,
an increasing number of users are using these services in their daily lives. The huge volume of information generated by users raises new opportunities in various applications
and areas. Inferring user interests plays a significant role in providing personalized
recommendations on microblogging services, and also on third-party applications
providing social logins via these services, especially in cold-start situations. In this
survey, we review user modeling strategies with respect to inferring user interests
from previous studies. To this end, we focus on four dimensions of inferring user
interest profiles: (1) data collection, (2) representation of user interest profiles, (3)
construction and enhancement of user interest profiles, and (4) the evaluation of the
constructed profiles. Through this survey, we aim to provide an overview of state-of-the-art user modeling strategies for inferring user interest profiles on microblogging
social networks with respect to the four dimensions. For each dimension, we review
and summarize previous studies based on specified criteria. Finally, we discuss some
challenges and opportunities for future work in this research domain
Analyzing MOOC Entries of Professionals on LinkedIn for User Modeling and Personalized MOOC Recommendations
The main contribution of this work is the comparison of
three user modeling strategies based on job titles, educational
fields and skills in LinkedIn profiles, for personalized MOOC
recommendations in a cold start situation. Results show
that the skill-based user modeling strategy performs best,
followed by the job- and edu-based strategies
- …