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Background: There are no large reported series determining the Covid-19 cancer patient's characteristics. We determine whether differences exist in cumulative incidence and mortality of Covid-19 infection between cancer patients and general population in Madrid. Material and methods: We reviewed 1069 medical records of all cancer patients admitted at Oncology department between Feb 1 and April 7, 2020. We described Covid-19 cumulative incidence, treatment outcome, mortality, and associated risk factors. Results: We detected 45/1069 Covid-19 diagnoses in cancer patients vs 42,450/6,662,000 in total population (p < 0.00001). Mortality rate: 19/45 cancer patients vs 5586/42,450 (p = 0.0001). Mortality was associated with older median age, adjusted by staging and histology (74 vs 63.5 years old, OR 1.06, p = 0.03). Patients who combined hydroxychloroquine and azithromycin presented 3/18 deaths, regardless of age, staging, histology, cancer treatment and comorbidities (OR 0.02, p = 0.03). Conclusion: Cancer patients are vulnerable to Covid-19 with an increase in complications. Combined hydroxychloroquine and azithromycin is presented as a good treatment option. [ABSTRACT FROM AUTHOR]

The authors describe a graphite immobilized bismuth film electrode with enhanced sensitivity for the organophosphorus pesticide paraoxon. The film was formed by ex-situ electroplating of bismuth onto the large surface of a glassy carbon electrode modified with graphite nanopowder (Bi/Gr/GCE). The modified GCE was characterized by chronoamperometry using p-nitrophenol as a model nitro compound. The modification of the GCE results in an increase of the electroactive area (to 27.7 mm) and of the electrocatalytic activity (the catalytic rate constant being 4140 L·mol·s). This results in an enhancement of the current for the electroreduction of paraoxon by a factor of 4.3 (compared to a plain GCE). The modified GCE was applied to the sensitive determination of paraoxon by differential pulse voltammetry. At a typical working potential of −0.45 V vs. Ag/AgCl, the LOD is 2 nmol·L of paraoxon, which is comparable to the LOD of some cholinesterases-based electrochemical sensors and is lower than the LOD of the organophosphorus hydrolase-based electrochemical sensors for paraoxon. In addition, the new GCE is more stable than enzyme-based sensors, and it can be renewed. [ABSTRACT FROM AUTHOR]

The effects of silvicultural treatments on carbon sequestration are poorly understood, particularly in areas like the Mediterranean where soil fertility is low and climatic conditions can be harsh. In order to improve our understanding of these effects, a long-term thinning experiment in a stand of Mediterranean maritime pine ( Pinus pinaster Ait.) was studied to identify the effects of thinning on soil carbon (forest floor and mineral soil), above and belowground biomass and fine and coarse woody debris. The study site was a 59-year-old pinewood, where three thinnings of differing intensities were applied: unthinned (control), moderate thinning and heavy thinning. The three thinning interventions (for the managed plots) involved whole-tree harvesting. The results revealed no differences between the different thinning treatments as regards the total soil carbon pool (forest floor + mineral soil). However, differences were detected in the case of living aboveground biomass and total dead wood debris between unthinned and thinned plots; the former containing larger amounts of carbon. The total carbon present in the unthinned plots was 317 Mg ha; in the moderately thinned plots, it was 256 Mg ha and in the case of heavily thinned plots, 234 Mg ha. Quantification of these carbon compartments can be used as an indicator of total carbon stocks under different forest management regimes and thus identify the most appropriate to mitigate the effects of global change. Our results indicated that thinning do not alter the total soil carbon content at medium term, suggesting the sustainability of these silvicultural treatments. [ABSTRACT FROM AUTHOR]

The article focuses on the study which uses finite element method (FEM) to simulate the air quality in local scale area in La Palma island in Canary Islands, Spain. The study is investigated by generating adaptive tetrahedral mesh, computating ambient wind field, and including the plume rise effect in the wind field. Results show that the proposed method can be useful in simulating the quality of air in complex terrain areas.

Changing biotic and abiotic stress mediate in plant–plant interactions resulting in positive to neutral or negative effects, and these effects can change with gradients of stress or through plant dynamics. Here we studied the variability in annual grass production and composition induced by gradients of intercepted light by trees in years of contrasting precipitation in Mediterranean holm oak open woodlands. Although trees reduce the light radiance received by the pasture community, the presence of trees generally had a positive effect on pasture production in average climatic years where soil fertility was low. However, the interaction changed with increasing abiotic water stress. In a dry year, the increase in fertility could not be utilized and the effect of the crown was neutral. The effect of shade turned out to be beneficial for growth, contrary to the situation in an average climatic year. Light insolation was positive for legume biomass. There was high variability in functional components over the course of the growing period and from 1 year to another. Under low levels of other biotic stresses such as livestock grazing or root competition, the limiting factor among light, soil moisture or soil nutrients may determine whether facilitation or competition occurs. [ABSTRACT FROM AUTHOR]

Despite Quercus ilex L. being one of the most widespread tree species in the Mediterranean basin, there are no growth models in the literature for this species. In this study, we compare age-dependent and age-independent dynamic diameter growth models and discuss the concept of dominance in open stands. A posteriori dominance was determined to fit potential age-dependent growth models and a site index based on diameter growth was defined. Formulations derived from power decline base models (Korf and Hossfeld) best described diameter growth. The best approach for age-dependent models was a polymorphic and with variable asymptotes generalized algebraic difference approach formulation. Residual errors in trees between 20 and 55 cm ranged from ~7.0% in potential growth models to ~15% in age-independent models expanded by density. Using a unique age-dependent dynamic equation for all trees, regardless of dominance, did not increase the error very much. In age-independent models, the inclusion of the defined site index reduced the prediction error but requires that the age of trees is estimated to determine the site index. The difficulty of estimating Q. ilex age makes age-independent models very attractive for system modelling. Age-independent models could be useful in other ecosystems where age estimation is problematic. Bien que Quercus ilex L. soit une des essences les plus répandues dans le bassin méditerranéen, la littérature n’offre pas de modèle de croissance pour cette essence. Dans cette étude, nous comparons les modèles dynamiques de croissance diamétrale dépendants et indépendants de l’âge et nous discutons du concept de dominance en peuplements ouverts. Une dominance a posteriori est déterminée pour ajuster les modèles de croissance potentielle dépendants de l’âge. En outre, un indice de qualité de station basé sur la croissance diamétrale est développé. Les formulations mathématiques dérivées des équations à puissance décroissante (Korf et Hossfeld) décrivent le mieux la croissance diamétrale. La meilleure approche pour les modèles dépendants de l’âge est celle de la formulation polymorphique à asymptote variable par la méthode de la différence algébrique généralisée. L’erreur résiduelle pour les arbres de 20 à 55 cm varie d’environ 7 % pour les modèles de croissance potentielle à environ 15 % pour les modèles indépendants de l’âge avec l’ajout de la densité. L’emploi d’une équation unique dépendante de l’âge pour tous les arbres, sans égard à leur dominance, ne fait pas beaucoup augmenter l’erreur. L’inclusion de l’indice de qualité de station dans les modèles indépendants de l’âge réduit l’erreur de prévision, mais requiert l’estimation de l’âge des arbres pour déterminer l’indice de qualité de station. La difficulté à estimer l’âge de Q. ilex rend les modèles indépendants de l’âge très attrayants pour modéliser sa croissance. Les modèles indépendants de l’âge pourraient être utiles dans d’autres écosystèmes où l’âge est difficile à évaluer. [ABSTRACT FROM AUTHOR]

Presents a study which compared vapor pressure measurements of quinizarin and leuco-quinizarin via transpiration and thermogravimetry. Methods for determining vapour pressure; Results and discussion; Information on thermogravimetric vapor pressure method.

Parallel preconditioners are presented for the solution of general linear systems of equations. The computation of these preconditioners is achieved by orthogonal projections related to the Frobenius inner product. So, minM∈&Sscr;∥AM-I∥ F and matrix M0∈&Sscr; corresponding to this minimum (&Sscr; being any vectorial subspace of &Mscr;n(ℝ)) are explicitly computed using accumulative formulae in order to reduce computational cost when subspace &Sscr; is extended to another one containing it. Every step, the computation is carried out taking advantage of the previous one, what considerably reduces the amount of work. These general results are illustrated with the subspace of matrices M such that AM is symmetric. The main application is developed for the subspace of matrices with a given sparsity pattern which may be constructed iteratively by augmenting the set of non-zero entries in each column. Finally, the effectiveness of the sparse preconditioners is illustrated with some numerical experiments. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Purpose The purpose is to know the stability of the taken registries basic of eye by means of non‐Mydriatic retinography. Methods The sample has been of 20 eyes of young people of both sexes between 19 and 35 years old. The measurements were carried out with a non‐mydriatic retinal camera model Topcon TRC‐NW8 in mesopic conditions maintaining the fixation point stable. The number of times in wich each eye was measured was 10. Two coordinates in each of the five points determined were located, points that are: P1_First intersection point between the nasal Vein superior and papilla; P2_First intersection point between the nasal Artery inferior with papilla; P3_First intersection point of the nasal Vein inferior with papilla (the direction always was according to the needles of the clock); P4_First Bifurcation nasal Vein; P5 superior_First Bifurcation nasal Artery superior. For the statistic analysis was used the Statgraphics plus 5.0. Results OD: x1= 2735.7 ± 18.1,y1= 1248.6 ± 8.12,x2= 2821 ± 20,y2= 1599.1 ± 11.94,x3= 2888.6 ± 18.88,y3= 1554.5 ± 9.8,x4= 2727.5 ± 19.2,y4= 1095.5 ± 9.9,x5= 2347.5 ± 18.7,y5= 609 ± 12 OI:x1= 1511.36 ± 6.5,y1= 1153 ± 12.5,x2= 1507.36 ± 7.2,y2= 1512.63 ± 14.7,x3= 1432.45 ± 8.2,y3= 1497.36± 13.2,x4= 1691.36 ± 6.5,y4= 988.72 ± 13.1,x5= 1833.18 ± 8.2,y5= 840.54 ± 10.8 The measurements obtained with non‐mydriatic retinal camera are very similar, therefore, the variations of the deviation only oscillated between the 0,16% and 4,85% Conclusion The reproducibility of the registries of non‐mydriatic retinal camera is very elevated for the selected points. These results enable us to consider the retina as a key element to implement in new security devices. [ABSTRACT FROM AUTHOR]