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Josep Pane,1,2 Katia MC Verhamme,1 Dorian Villegas,2 Laura Gamez,3 Irene Rebollo,3 Miriam CJM Sturkenboom4 1Department of Medical Informatics, Erasmus Medical Center, University of Rotterdam, Rotterdam, Netherlands; 2Alcon, Fort Worth, USA; 3Novartis, Barcelona, Spain; 4Julius Global Health, University Medical Center Utrecht, Utrecht, NetherlandsCorrespondence: Josep PaneDepartment of Medical Informatics, Erasmus Medical Center, University of Rotterdam, Rotterdam, 3000, CA, NetherlandsEmail jpanesalvado@gmail.comBackground: Previous safety issues involving medical devices have stressed the need for better safety signal detection. Various European Union (EU) national competent authorities have started to focus on strengthening the analysis of vigilance data. Consequently, article 90 of the new EU regulation states that the European Commission shall put in place systems and processes to actively monitor medical device safety signals.Methods: A systematic literature review was conducted to synthesize the current state of knowledge and investigate the present tools used for medical device safety signal detection. An electronic literature search was performed in Embase, Medline, Cochrane, Web of science, and Google scholar from inception until January 2017. Articles that included terms related to medical devices and terms associated with safety were selected. A further selection was based on the abstract review. A full review of the remaining articles was conducted to decide on which articles finally to consider relevant for this review. Completeness was assessed based on the content of the articles.Results: Our search resulted in a total of 20,819 articles, of which 24 met the inclusion criteria and were subject to data extraction and completeness scoring. A wide range of data sources, especially spontaneous reporting systems and registries, used for the detection and assessment of product problems and patient harms associated with the use of medical devices, were studied. Coding is remarkably heterogeneous, no agreement on the preferred methods for signal detection exists, and no gold standard for signal detection has been established thus far.Conclusion: Data source harmonization, the development of gold standard signal detection methodologies and the standardization of coding dictionaries are amongst the recommendations to support the implementation of a new proactive approach to signal detection. The new safety surveillance system will be able to use real-world evidence to support regulatory decision-making across all jurisdictions.Keywords: signal detection, safety surveillance, post-market surveillance, post-market data sources, coding dictionaries, medical devices

Gomortega keule (Mol.) Baillon es un árbol endémico de Chile, que se encuentra actualmente en peligro de extinción. Aunque los patrones de regeneración de la especie se desconocen, algunos autores aluden a una generalizada escasez de plántulas. Este artículo presenta una investigación de la estructura poblacional y los patrones de regeneración de G. keule en un bosque antiguo en Caramávida, Cordillera de Nahuelbuta. Los objetivos fueron (i) determinar el patrón de regeneración que esta especie ha presentado en el pasado, (ii) verificar si existe actualmente regeneración sexual de G. keule y (iii) caracterizar los ambientes lumínicos en que ésta se produce. En una parcela de 0,24 ha se midió el diámetro a la altura de pecho (DAP) y la posición espacial de cada uno de los árboles de G. keule y de dos de las especies más comunes asociadas (Aextoxicon punctatum y Eucryphia cordifolia). Se usaron dos analizadores de doseles LAI-2000 para medir los ambientes lumínicos sobre cada plántula de G. keule. La irregularidad en la distribución diamétrica de G. keule y la asociación de las plántulas con un claro reciente en la parcela sugieren un patrón de regeneración episódica por apertura de claros. Aunque actualmente hay plántulas en el rodal, los bajos niveles de luz prevalecientes en el sotobosque hacen dudar de sus posibilidades de supervivencia. Al parecer G. keule sería una especie más intolerante a la sombra que las otras dos especies analizadas que muestran evidencias de regeneración más continua. La conservación y restauración de poblaciones de esta especie requerirá complementar esta primera investigación demográfica con otras semejantes, además de mejorar el conocimiento de otros aspectos de su biologíaGomortega keule is an endemic Chilean tree currently in danger of extinction. Although the regeneration patterns of the species are poorly-understood, some authors have alluded to a widespread lack of seedlings in established populations. Past regeneration patterns were inferred from diameter distributions in a population of G. keule in an old-growth stand at Caramávida in south-central Chile. These data were compared with those of two of its most common associates, Aextoxicon punctatum and Eucryphia cordifolia. Seedling light environments were also measured in order to identify the conditions that favour sexual regeneration of the species. Results suggest that sexual regeneration of G. keule requires considerable canopy opening. On the other hand, A. punctatum shows evidence of continuous regeneration and E. cordifolia shows a strong tendency to reproduce by suckering. G. keule appears to be more shade-intolerant than the other two species studied. The irregularity of G. keule `s diameter distribution, and the association of seedlings with a recent canopy opening on the plot, suggest a strongly discontinuous regeneration pattern. Although seedlings of G. keule were present on the plot, these seem unlikely to survive in the low light levels now prevailing in the partially closed gap where they established. G. keule appears to be less shade tolerant than the other two species studied, which show evidence of more continuous regeneration. Conservation and restoration of populations of G. keule will require further demographic studies, as well as research on other aspects of the biology of the species

To understand yield limitations imposed by the source-sink relationship and the effects that breeding had on it, the source-sink ratio was modified on 24 durum wheat cultivars released in different periods. Field experiments were conducted during 3 yr, with treatments consisting of removing the flag-leaf blade, degraining half of the spike, and intact checks. Grains from near-basal spikelets tended to be the most sensitive to source-sink modifications. Degraining increased grain weight up to 15% in modern cultivars, which were more source limited and more responsive to source-sink modifications than the old ones. Our results suggest a source-sink colimitation for grain filling in Mediterranean environments. Translocation of preanthesis assimilates was responsible for 25, 27, and 33% of grain weight in old, intermediate, and modern cultivars, respectively. Defoliation did not alter dry matter translocation (DMT) from the main stem, as the reduction in translocation of leaf blades was compensated with translocation increases from the chaff. Sink demand determined DMT that was mostly regulated by the stem. Our results indicate that future yield improvements may be achieved by strengthening the source capacity.

The effect of environment on the relationship between grain carbon isotope discrimination (Δ) and yield was studied for durum wheat (Triticum turgidum L. var. durum) under Mediterranean conditions. A group of 25 genotypes was grown under contrasting water regimes in two regions of Spain during three years. The first objective was to determine the environmental factors responsible for the strong positive relationship previously observed between Δ and yield across trials. Environmental factors tested were total water input ([W.sub.i]), mean temperature, accumulated reference evapotranspiration (E[T.sub.0]), and the ratio [W.sub.i]/E[T.sub.0] during different periods of the crop cycle. Water input during grain filling was the variable most strongly correlated with grain Δ and yield across all the trials, as well as across the subset of trials in northeastern Spain. In southeastern Spain, the most drought prone of the two regions, [W.sub.i] from sowing to heading explained the most variation in grain Δ and yield. The second objective was to study the effect of environment on the relationship between Δ and yield across genotypes. NO significant correlation was found for trials with a mean yield up to about 2000 kg [ha.sup.-1], but the strength of the relationship increased sharply and attained significance in trials yielding 2500 kg [ha.sup.-1]. When yield above 2500 kg [ha.sup.-1] the correlation between Δ and yield remained relatively steady and positive, with an r value around 0.5. It is concluded that breeding to raise durum wheat yield in Mediterranean conditions could take advantage of selecting for higher Δ only in relatively wet years or under supplementary irrigation., DROUGHT, defined as water deficit, and often combined with high temperature stress, is one of the greatest constraints to cereal grain yield in Mediterranean areas. For crops such as durum [...]

Future wheat yield improvements may be gained by increasing total dry matter (TDM) production. Vegetation indices (VI) based on spectral reflectance ratios have been proposed as an appropriate method to assess TDM and leaf area index (LAI) in wheat. This study was undertaken to determine whether VI could accurately identify TDM and LAI in durum wheat {Triticum turgidum var. durum (Desf.) Bowden [= T. turgidum subsp, durum (Desf.) Husn.]} and serve as indirect selection criteria in breeding programs. Total dry matter and LAI were determined from destructive sampling from booting to milk-grain in seven field experiments conducted under Mediterranean conditions. Each experiment included one of two sets of 20 or 25 genotypes. Field reflectance values were collected using a portable field spectroradiometer. Two VI, the normalized difference vegetation index (NDVI) and the simple ratio (SR), were derived from spectral measurements and their predictive value for TDM and LAI was evaluated. The best stages for growth trait appraisal were Stages 65 and 75 of the Zadoks scale. The power of VI for assessing TDM was lower than their predictive value for LAI. The suitability of VI for the assessment of growth traits depended on the range of variability existing within the experimental data. Vegetation indices accurately tracked changes in LAI when data were analyzed across a broad range of different growth stages, environments, and genotypes. However, their value as indirect genotypic selection criteria for TDM or LAI was limited, since they lacked predictive ability for specific environment/ growth stage combinations., GAIN YIELD may be defined as a product of the TDM of the crop and its harvest index (Donald and Hamblin, 1976). In the past, increases in bread wheat yields [...]