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Molitor D.,LIST Luxembourg Institute of Science and Technology | Molitor D.,University of Natural Resources and Life Sciences, Vienna | Keller M.,Washington State University
Journal International des Sciences de la Vigne et du Vin | Year: 2016

Methods and results: Window pane analysis showed that pre-bloom and bloom minimum temperatures and precipitation sums in the preceding year, winter temperatures, spring temperatures, and post-veraison minimum temperatures in the current year were positively correlated with annual yield; early spring and post-harvest temperatures in the preceding year, and, for Riesling, pre-bloom precipitation sums and post-bloom maximum temperatures in the current year were negatively correlated with annual yield. Models developed from these data simulated annual yield with high accuracy (R2adj = 0.88 for Riesling, and R2adj = 0.92 for Müller-Thurgau). Conclusions: Meteorological conditions during distinct periods of yield formation are correlated with annual yield. Yield models can be used in practical viticulture as well as in climate change impact studies. Significance and impact of the study: Enhanced understanding of the effects of meteorological conditions during specific periods of yield formation supports growers' efforts to optimize viticultural measures aimed at achieving adequate yield levels. © Université de Bordeaux (Bordeaux, France).


Molitor D.,LIST Luxembourg Institute of Science and Technology | Molitor D.,University of Natural Resources and Life Sciences, Vienna | Augenstein B.,Geosens Ingenieurpartnerschaft | Mugnai L.,University of Florence | And 9 more authors.
European Journal of Plant Pathology | Year: 2015

Black rot on grapevine is a fungal disease caused by Phyllosticta ampelicida (syn. Guignardia bidwellii) affecting grape leaves as well as clusters. A novel black rot decision support system termed VitiMeteo Black rot was assembled based on existing sub-models and incorporated into the established VitiMeteo forecast and decision support platform. Based on local weather data and a 5-day weather forecast, VitiMeteo Black rot simulates the relative susceptibility of grape clusters, the occurrence and severity of infection events as well as the duration of incubation periods. Data sets obtained in extended international (14 case studies; eight monitoring locations; 11 cultivars; seven countries in Europe and North America) field monitoring campaigns in 2012 and 2013 were used to evaluate the model predictions of newly expressed symptoms on leaves. In the case of the Vitis vinifera cultivars, on average 26.3 disease assessments took place per season. On average, 9.9 predictions were classified as true positive, 8.0 as true negative, 5.2 as false positive and 3.2 as false negative. Model precision, sensitivity and accuracy were on average 64, 77 and 67 %. Potential reasons for false positive and false negative predictions are discussed. VitiMeteo Black rot is freely available for several locations in Germany, Luxembourg and Austria on the internet via the VitiMeteo platform and might be expanded to other regions in the future. © 2015 Koninklijke Nederlandse Planteziektenkundige Vereniging


Molitor D.,LIST Luxembourg Institute of Science and Technology | Molitor D.,University of Natural Resources and Life Sciences, Vienna | Udelhoven T.,LIST Luxembourg Institute of Science and Technology | Udelhoven T.,University of Trier | And 3 more authors.
Vitis - Journal of Grapevine Research | Year: 2016

Verbal vintage descriptions in a historical wine chronicle (809-1904) of the Luxembourgish winegrowing region were assigned to five wine quality and three wine quantity classes. To calibrate models describing the impact of the seasonal heat consumption on wine quality and quantity, instrumental records from Luxembourg-City in a reference period (1854-1885) and the associated vintage quality and quantity classes were correlated. Dummy regression models showed, that in the reference period the wine quality classes assigned were significantly correlated with the annual modified heliothermic index values (representing the heat consumption) (R2 adj. = 0.55, p = 0.0002); whereas, the incorporation of the wine quantity as additional predictor variable did not significantly improve model output. Based on linear correlations between annual thermal conditions and wine quality descriptions, average April-September temperatures were reconstructed for the period 1200-1904. Running averages calculated using LOESS smoothing showed that periods with cooler and warmer climatic conditions alternated in the past centuries. Even though a precise reconstruction of the annual temperature conditions solely based on vintage descriptions is not possible due to the broad set of potentially interfering effects, long-term climatic trends described in the literature such as the Medieval Climate Optimum and the Little Ice Age could be retrieved. © The author(s).


Boudjeloud-Assala L.,University of Lorraine | Pinheiro P.,LIST Luxembourg Institute of Science and Technology | Blansche A.,University of Lorraine | Tamisier T.,LIST Luxembourg Institute of Science and Technology | Otjacques B.,LIST Luxembourg Institute of Science and Technology
Information Visualization | Year: 2016

This article proposes a semi-interactive system for visual data exploration using an iterative clustering that combines an automatic approach with an interactive one. We propose a framework to improve the interactivity between the user and the data analysis process, allowing him or her to participate actively in the iterative clustering tasks using a two-dimensional projection. Defining a cluster by its seed (center) and its limit, the proposed approach allows the user to modify the automated values or to define new seeds and the associated cluster limit himself or herself. The user can perform the clustering according to his or her visual perception manually and can also choose to let the automated approach find optimal seeds and then interact with the process to iterate the clustering process according to his or her visual perception and domain knowledge. Most of the evaluation criteria for clustering evaluate the complete clustering and not each cluster separately. In this article, we propose to adapt evaluation criteria to single clusters, allowing the users to evaluate their own clusters and perform the clustering iteratively until satisfaction. To evaluate our proposed approach, we conduct a user evaluation, where the users are asked to perform clustering interactively according to their visual perception and with the semi-interactive one. We also compare the obtained results with those of automated clustering. The quantitative results have shown that the cooperative approach can improve the clustering results in terms of accuracy. © The Author(s) 2015.


Boudjeloud-Assala L.,CNRS Theoretical and Applied Informatics | Pinheiro P.,LIST Luxembourg Institute of Science and Technology | Blansche A.,CNRS Theoretical and Applied Informatics | Tamisier T.,LIST Luxembourg Institute of Science and Technology | Otjaques B.,LIST Luxembourg Institute of Science and Technology
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2015

We propose in this paper a new approach to detect and visualize the change in a streaming clustering. This approach can be used to explore visually the data streams. We assume that the data stream structure can be different during the time. Our objective is to alert the user on the structure change during the time period. A common approach to deal with data streams is to observe and process it in a window. The principle of the proposed approach is to apply a data exploration method on each window. We then propose to visualize the change between all windows for each extracted cluster. The user can investigate more precisely the change between the two windows through a visual projection for each extracted cluster. © Springer International Publishing Switzerland 2015.


Zamborlini V.,VU University Amsterdam | Zamborlini V.,LIST Luxembourg Institute of Science and Technology | Hoekstra R.,VU University Amsterdam | Hoekstra R.,University of Amsterdam | And 4 more authors.
HEALTHINF 2016 - 9th International Conference on Health Informatics, Proceedings; Part of 9th International Joint Conference on Biomedical Engineering Systems and Technologies, BIOSTEC 2016 | Year: 2016

This paper presents a method for formally representing Computer-Interpretable Guidelines to deal with multimorbidity. Although some approaches for merging guidelines exist, improvements are still required for combining several sources of information and coping with possibly conflicting pieces of evidence coming from clinical studies. Our main contribution is twofold: (i) we provide general models and rules for representing guidelines that expresses evidence as causation beliefs; (ii) we introduce a mechanism to exploit external medical knowledge acquired from Linked Open Data (Drugbank, Sider, DIKB) to detect potential interactions between recommendations. We apply this framework to merge three guidelines (Osteoarthritis, Diabetes, and Hypertension) in order to illustrate the capability of this approach for detecting potential conflicts between guidelines and eventually propose alternatives. Copyright © 2016 by SCITEPRESS - Science and Technology Publications, Lda. All rights reserved.


Zamborlini V.,VU University Amsterdam | Zamborlini V.,LIST Luxembourg Institute of Science and Technology | Hoekstra R.,VU University Amsterdam | Hoekstra R.,University of Amsterdam | And 4 more authors.
Semantic Web | Year: 2016

The formal representation of clinical knowledge is still an open research topic. Classical representation languages for clinical guidelines are used to produce diagnostic and treatment plans. However, they have important limitations, e.g. when looking for ways to re-use, combine, and reason over existing clinical knowledge. These limitations are especially problematic in the context of multimorbidity; patients that suffer from multiple diseases. To overcome these limitations, this paper proposes a model for clinical guidelines (TMR4I) that allows the re-use and combination of knowledge from multiple guidelines. Semantic Web technology is applied to implement the model, allowing us to automatically infer interactions between recommendations, such as recommending the same drug more than once. It relies on an existing Linked Data set, DrugBank, for identifying drug-drug interactions. We evaluate the model by applying it to two realistic case studies on multimorbidity that combine guidelines for two (Duodenal Ulcer and Transient Ischemic Attack) and three diseases (Osteoarthritis, Hypertension and Diabetes) and compare the results with existing methods. © 2016 - IOS Press and the authors.


Corte-Real J.,LIST Luxembourg Institute of Science and Technology | Corte-Real J.,University of Kaiserslautern | Iddir M.,LIST Luxembourg Institute of Science and Technology | Soukoulis C.,LIST Luxembourg Institute of Science and Technology | And 3 more authors.
Food Chemistry | Year: 2016

During digestion, high concentrations of divalent minerals (DMs) can lead to insoluble lipid-soap complex formation, hampering carotenoid bioaccessibility. The effect of varying concentrations (0-1000 mg/L) of calcium, magnesium, zinc and sodium (control) on the bioaccessibility of lutein, neoxanthin, lycopene and β-carotene, following in vitro gastro-intestinal digestion (GI), was investigated systematically and coupled with physical measurements of the digesta. Addition of DMs significantly decreased (p < 0.001) carotenoid bioaccessibility, up to 100% in the case of calcium. Mean half maximal inhibitory concentrations (EC50) for calcium, magnesium and zinc were 270 ± 18, 253 ± 75 and 420 ± 322 mg/L respectively. Increased DM concentrations correlated with decreased viscosity (r > 0.9) and decreased carotenoid bioaccessibility. Surface tension of digesta correlated inversely (p < 0.05) with the bioaccessibility of carotenoids. This correlation was mineral and carotenoid dependent. Although based on in vitro findings, it is plausible that similar interactions occur in vivo, with DMs affecting the bioaccessibility and bioavailability of carotenoids and other lipophilic micronutrients and phytochemicals. © 2015 Elsevier Ltd. All rights reserved.


PubMed | LIST Luxembourg Institute of Science and Technology and University of Kaiserslautern
Type: Journal Article | Journal: Food chemistry | Year: 2015

During digestion, high concentrations of divalent minerals (DMs) can lead to insoluble lipid-soap complex formation, hampering carotenoid bioaccessibility. The effect of varying concentrations (0-1000 mg/L) of calcium, magnesium, zinc and sodium (control) on the bioaccessibility of lutein, neoxanthin, lycopene and -carotene, following in vitro gastro-intestinal digestion (GI), was investigated systematically and coupled with physical measurements of the digesta. Addition of DMs significantly decreased (p<0.001) carotenoid bioaccessibility, up to 100% in the case of calcium. Mean half maximal inhibitory concentrations (EC50) for calcium, magnesium and zinc were 27018, 25375 and 420322 mg/L respectively. Increased DM concentrations correlated with decreased viscosity (r>0.9) and decreased carotenoid bioaccessibility. Surface tension of digesta correlated inversely (p<0.05) with the bioaccessibility of carotenoids. This correlation was mineral and carotenoid dependent. Although based on in vitro findings, it is plausible that similar interactions occur in vivo, with DMs affecting the bioaccessibility and bioavailability of carotenoids and other lipophilic micronutrients and phytochemicals.

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