110 research outputs found
Challenges and Requirements for Introducing Impairment-awareness into the Management and Control Planes of ASON/GMPLS WDM Networks
The absence of electrical regenerators in transparent WDM networks significantly contributes to reduce the overall network cost. In transparent WDM networks, a proper resource allocation requires that the presence of physical impairments in Routing and Wavelength Assignment (RWA) and lightpath provisioning be taken into account. In this article a centralized, a hybrid centralized-distributed and two distributed approaches that integrate information about most relevant physical impairments in RWA and
lightpath provisioning are presented and assessed. Both centralized and hybrid approaches perform a centralized path computation at the management-plane level, utilizing physical
impairment information, while the lightpath provisioning is done by the management plane or the control plane, respectively. The distributed approaches fall entirely within the scope of the
ASON/GMPLS control plane. For these two approaches, we provide functional requirements, architectural functional blocks, and protocol extensions for implementing either an impairment-aware real-time RWA, or a lighpath provisioning based on impairment-aware signaling
Joint data analysis in nutritional epidemiology: Identification of observational studies and minimal requirements
Background: Joint data analysis from multiple nutrition studies may improve the ability to answer complex questions regarding the role of nutritional status and diet in health and disease.Objective: The objective was to identify nutritional observational studies from partners participating in the European Nutritional Phenotype Assessment and Data Sharing Initiative (ENPADASI) Consortium, as well asminimal requirements for joint data analysis.Methods: A predefined template containing information on study design, exposure measurements (dietary intake, alcohol and tobacco consumption, physical activity, sedentary behavior, anthropometric measures, and sociodemographic and health status), main health-related outcomes, and laboratory measurements (traditional and omics biomarkers) was developed and circulated to those European research groups participating in the ENPADASI under the strategic research area of "diet-related chronic diseases." Information about raw data disposition and metadata sharing was requested. A set of minimal requirements was abstracted from the gathered information.Results: Studies (12 cohort, 12 cross-sectional, and 2 case-control) were identified. Two studies recruited children only and the rest recruited adults. All studies included dietary intake data. Twenty studies collected blood samples. Data on traditional biomarkers were available for 20 studies, of which 17 measured lipoproteins, glucose, and insulin and 13 measured inflammatory biomarkers. Metabolomics, proteomics, and genomics or transcriptomics data were available in 5, 3, and 12 studies, respectively. Although the study authors were willing to share metadata, most refused, were hesitant, or had legal or ethical issues related to sharing raw data. Forty-one descriptors of minimal requirements for the study data were identified to facilitate data integration.Conclusions: Combining study data sets will enable sufficiently powered, refined investigations to increase the knowledge and understanding of the relation between food, nutrition, and human health. Furthermore, t he minimal requirements for study data may encourage more efficient secondary usage of existing data and provide sufficient information for researchers to draft future multicenter research proposals in nutrition
Effects of Dietary Fibers on Short-Chain Fatty Acids and Gut Microbiota Composition in Healthy Adults: A Systematic Review
There is an increasing interest in investigating dietary strategies able to modulate the gut microbial ecosystem which, in turn, may play a key role in human health. Dietary fibers (DFs) are widely recognized as molecules with prebiotic effects. The main objective of this systematic review was to: (i) analyze the results available on the impact of DF intervention on short chain fatty acids (SCFAs) production; (ii) evaluate the interplay between the type of DF intervention, the gut microbiota composition and its metabolic activities, and any other health associated outcome evaluated in the host. To this aim, initially, a comprehensive database of literature on human intervention studies assessing the effect of confirmed and candidate prebiotics on the microbial ecosystem was developed. Subsequently, studies performed on DFs and analyzing at least the impact on SCFA levels were extracted from the database. A total of 44 studies from 42 manuscripts were selected for the analysis. Among the different types of fiber, inulin was the DF investigated the most (n = 11). Regarding the results obtained on the ability of fiber to modulate total SCFAs, seven studies reported a significant increase, while no significant changes were reported in five studies, depending on the analytical methodology used. A total of 26 studies did not show significant differences in individual SCFAs, while the others reported significant differences for one or more SCFAs. The effect of DF interventions on the SCFA profile seemed to be strictly dependent on the dose and the type and structure of DFs. Overall, these results underline that, although affecting microbiota composition and derived metabolites, DFs do not produce univocal significant increase in SCFA levels in apparently healthy adults. In this regard, several factors (i.e., related to the study protocols and analytical methods) have been identified that could have affected the results obtained in the studies evaluated. Future studies are needed to better elucidate the relationship between DFs and gut microbiota in terms of SCFA production and impact on health-related markers
ONS : an ontology for a standardized description of interventions and observational studies in nutrition
Background: The multidisciplinary nature of nutrition research is one of its main strengths. At the same time, however, it presents a major obstacle to integrate data analysis, especially for the terminological and semantic interpretations that specific research fields or communities are used to. To date, a proper ontology to structure and formalize the concepts used for the description of nutritional studies is still lacking.
Results: We have developed the Ontology for Nutritional Studies (ONS) by harmonizing selected pre-existing de facto ontologies with novel health and nutritional terminology classifications. The ONS is the result of a scholarly consensus of 51 research centers in nine European countries. The ontology classes and relations are commonly encountered while conducting, storing, harmonizing, integrating, describing, and searching nutritional studies. The ONS facilitates the description and specification of complex nutritional studies as demonstrated with two application scenarios.
Conclusions: The ONS is the first systematic effort to provide a solid and extensible formal ontology framework for nutritional studies. Integration of new information can be easily achieved by the addition of extra modules (i.e., nutrigenomics, metabolomics, nutrikinetics, and quality appraisal). The ONS provides a unified and standardized terminology for nutritional studies as a resource for nutrition researchers who might not necessarily be familiar with ontologies and standardization concepts
ONS: An ontology for a standardized description of interventions and observational studies in nutrition
Background: The multidisciplinary nature of nutrition research is one of its main strengths. At the same time, however, it presents a major obstacle to integrate data analysis, especially for the terminological and semantic interpretations that specific research fields or communities are used to. To date, a proper ontology to structure and formalize the concepts used for the description of nutritional studies is still lacking.Results: We have developed the Ontology for Nutritional Studies (ONS) by harmonizing selected pre-existing de facto ontologies with novel health and nutritional terminology classifications. The ONS is the result of a scholarly consensus of 51 research centers in nine European countries. The ontology classes and relations are commonly encountered while conducting, storing, harmonizing, integrating, describing, and searching nutritional studies. The ONS facilitates the description and specification of complex nutritional studies as demonstrated with two application scenarios.Conclusions: The ONS is the first systematic effort to provide a solid and extensible formal ontology framework for nutritional studies. Integration of new information can be easily achieved by the addition of extra modules (i.e., nutrigenomics, metabolomics, nutrikinetics, and quality appraisal). The ONS provides a unified and standardized terminology for nutritional studies as a resource for nutrition researchers who might not necessarily be familiar with ontologies and standardization concepts
Effect of photoperiod on sexual activity of boar
The main objective of this study was to assess the effect of photoperiod on sexual activity of three breeds of boars: Swedish Landrace (n=34), Large White (n=38), and Duroc (n=32). Boar sexual activity was analysed based on the libido index and intensity of ejaculation. The libido index was calculated as the ratio between the duration of ejaculation and time of preparation until ejaculation. The intensity of ejaculation was the volume of ejaculate (mL) secreted in the unit of time (min). The effect of photoperiod was analysed as the effect of duration of daylight ( lt 12 h and >12 h) within photoperiod intervals (increasing and decreasing). Impact assessment was carried out by applying the General Linear Model procedure. Libido and intensity of ejaculation varied under the impact of photoperiod and the breed of boars. With the increase in age, the boar libido weakened, while the volume of ejaculate and intensity of ejaculation increased. Boars manifested better libido when the daylight lasted longer than 12 h in both photoperiod intervals. Different from libido, the volume of ejaculate and intensity of ejaculation were highest when the daylight was shorter than 12 h, but only in the decreasing photoperiod interval. Swedish Landrace boars manifested best libido, while in the production of sperm the Duroc boars were inferior compared with Swedish Landrace and Large White. The phenotypic relationship among libido, ejaculate volume, and ejaculation intensity ranges from very low to high; however, the coefficients were positive, which indicates the possibility of simultaneous improvement of these traits
Perspective: Essential study quality descriptors for data from nutritional epidemiologic research
Pooled analysis of secondary data increases the power of research and enables scientific discovery in nutritional epidemiology. Information on study characteristics that determine data quality is needed to enable correct reuse and interpretation of data. This study aims to define essential quality characteristics for data from observational studies in nutrition. First, a literature review was performed to get an insight on existing instruments that assess the quality of cohort, case-control, and cross-sectional studies and dietary measurement. Second, 2 face-to-face workshops were organized to determine the study characteristics that affect data quality. Third, consensus on the data descriptors and controlled vocabulary was obtained. From 4884 papers retrieved, 26 relevant instruments, containing 164 characteristics for study design and 93 characteristics for measurements, were selected. The workshop and consensus process resulted in 10 descriptors allocated to "study design" and 22 to "measurement" domains. Data descriptors were organized as an ordinal scale of items to facilitate the identification, storage, and querying of nutrition data. Further integration of an Ontology for Nutrition Studies will facilitate interoperability of data repositories
GRCBox: Extending Smartphone Connectivity in Vehicular Networks
The low penetration of connectivity-enabled OBUs is delaying the deployment of Vehicular Networks (VNs), and
therefore the development of Vehicular Delay Tolerant Network (VDTN) applications, among others. In this paper we
present GRCBox, an architecture based on RaspberryPi that allows integrating smartphones in VNs. GRCBox is based
on a low-cost device that combines several pieces of software to provide ad-hoc and multi-interface connectivity to
smartphones. Using GRCBox each application can choose the interface for its data flows, which increases flexibility
and will allow developers to easily implement applications based on ad-hoc connectivity, such as VDTN applications.This work was partially supported by the Ministerio de Economia y Competitividad, Spain, under Grants TIN2011-27543-C03-01 and BES-2012-052673, and by the European Commission under Svagata.eu, the Erasmus Mundus Programme, Action 2 (EMA2).MartĂnez Tornell, S.; Patra, S.; Tavares De Araujo Cesariny Calafate, CM.; Cano Escribá, JC.; Manzoni, P. (2015). GRCBox: Extending Smartphone Connectivity in Vehicular Networks. International Journal of Distributed Sensor Networks. 2015:1-13. doi:10.1155/2015/478064S1132015Hartenstein, H., & Laberteaux, K. P. (2008). A tutorial survey on vehicular ad hoc networks. IEEE Communications Magazine, 46(6), 164-171. doi:10.1109/mcom.2008.4539481Wu, H., Palekar, M., Fujimoto, R., Guensler, R., Hunter, M., Lee, J., & Ko, J. (2005). An empirical study of short range communications for vehicles. Proceedings of the 2nd ACM international workshop on Vehicular ad hoc networks - VANET ’05. doi:10.1145/1080754.1080769Jerbi, M., Senouci, S.-M., & Haj, M. A. (2007). Extensive Experimental Characterization of Communications in Vehicular Ad Hoc Networks within Different Environments. 2007 IEEE 65th Vehicular Technology Conference - VTC2007-Spring. doi:10.1109/vetecs.2007.533Lee, K. C., Lee, S., Cheung, R., Lee, U., & Gerla, M. (2007). First Experience with CarTorrent in a Real Vehicular Ad Hoc Network Testbed. 2007 Mobile Networking for Vehicular Environments. doi:10.1109/move.2007.4300814Giordano, E., Tomatis, A., Ghosh, A., Pau, G., & Gerla, M. (2008). C-VeT An Open Research Platform for VANETs: Evaluation of Peer to Peer Applications in Vehicular Networks. 2008 IEEE 68th Vehicular Technology Conference. doi:10.1109/vetecf.2008.462Cesana, M., Fratta, L., Gerla, M., Giordano, E., & Pau, G. (2010). C-VeT the UCLA campus vehicular testbed: Integration of VANET and Mesh networks. 2010 European Wireless Conference (EW). doi:10.1109/ew.2010.5483535Santa, J., Tsukada, M., Ernst, T., & Gomez-Skarmeta, A. F. (2009). Experimental analysis of multi-hop routing in vehicular ad-hoc networks. 2009 5th International Conference on Testbeds and Research Infrastructures for the Development of Networks & Communities and Workshops. doi:10.1109/tridentcom.2009.4976248Paula, M. C. G., Isento, J. N., Dias, J. A., & Rodrigues, J. J. P. C. (2011). A real-world VDTN testbed for advanced vehicular services and applications. 2011 IEEE 16th International Workshop on Computer Aided Modeling and Design of Communication Links and Networks (CAMAD). doi:10.1109/camad.2011.5941108Campbell, A., & Choudhury, T. (2012). From Smart to Cognitive Phones. IEEE Pervasive Computing, 11(3), 7-11. doi:10.1109/mprv.2012.41Vandenberghe, W., Moerman, I., & Demeester, P. (2011). On the feasibility of utilizing smartphones for vehicular ad hoc networking. 2011 11th International Conference on ITS Telecommunications. doi:10.1109/itst.2011.6060061Sawada, D., Sato, M., Uehara, K., & Murai, J. (2011). iDANS: A platform for disseminating information on a VANET consisting of smartphone nodes. 2011 11th International Conference on ITS Telecommunications. doi:10.1109/itst.2011.6060062Tornell, S. M., Calafate, C. T., Cano, J.-C., Manzoni, P., Fogue, M., & Martinez, F. J. (2013). Evaluating the Feasibility of Using Smartphones for ITS Safety Applications. 2013 IEEE 77th Vehicular Technology Conference (VTC Spring). doi:10.1109/vtcspring.2013.6692553Mitchell, G. (2012). The Raspberry Pi single-board computer will revolutionise computer science teaching. Engineering & Technology, 7(3), 26-26. doi:10.1049/et.2012.0300Fielding R. T.Architectural styles and the design of network-based software architectures [Ph.D. thesis]2000University of Californi
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