380 research outputs found

    Natural selection on plant resistance to herbivores in the native and introduced range

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    . When plants are introduced into new regions, the absence of their co-evolved natural enemies can result in lower levels of attack. As a consequence of this reduction in enemy pressure, plant performance may increase and selection for resistance to enemies may decrease. In the present study, we compared leaf damage, plant size and leaf trichome density, as well as the direction and magnitude of selection on resistance and plant size between non-native (Spain) and native (Mexico) populations of Datura stramonium. This species was introduced to Spain about five centuries ago and constitutes an ideal system to test four predictions of the enemy release hypothesis. Compared with native populations, we expected Spanish populations of D. stramonium to have (i) lower levels of foliar damage; (ii) larger plant size; (iii) lower leaf trichome density that is unrelated to foliar damage by herbivores; and (iv) weak or no selection on resistance to herbivores but strong selection on plant size. Our results showed that, on average, plants from non-native populations were significantly less damaged by herbivores, were less pubescent and were larger than those from native populations. We also detected different selection regimes on resistance and plant size between the non-native and native ranges. Positive selection on plant size was detected in both ranges (though it was higher in the non-native area), but consistent positive selection on relative resistance was detected only in the native range. Overall, we suggest that changes in selection pressure on resistance and plant size in D. stramonium in Spain are a consequence of ‘release from natural enemies’

    [S,S]-EDDS Ligand as a Soil Solubilizer of Fe, Mn, Zn, and Cu to Improve Plant Nutrition in Deficient Soils

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    The deficiencies of iron, manganese, zinc, and copper in calcareous soils are a worldwide problem affecting plant growth and fruit quality, usually minimized by the application of recalcitrant synthetic metal chelates. Biodegradable ligand [S,S]- EDDS is an eco-friendly substitute. This study investigates the capacity of [S,S]-EDDS to mobilize micronutrients from agronomic soils and improve plant nutrition. A batch and a plant experiment (Phaseolus vulgaris cv. Black Pole) with three agronomic soils was conducted to monitor the micronutrients solubilized by [S,S]-EDDS, the ligand degradation, and plant uptake. The results demonstrated the high capacity of [S,S]-EDDS to solubilize Fe and other micronutrients related to its chemical behavior and the enhancement of plant nutrition. The best results were shown in sandy-clay soil with low Fe, typically found in the Mediterranean areas. The results support the direct application of the ligand to soils and a possible biotechnological application of the ligandproducer bacteriaAuthors gratefully acknowledge the financial support by Spanish Ministry of Economy and Competitiveness project: RTI2018-096268-B-I00, and the Comunidad de Madrid (Spain) and Structural Funds 2014−2020 (ERDF and ESF) project AGRISOST-CM S2018/BAA-433

    Desarrollo de un repositorio de objetos de aprendizaje usando DSpace

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    El repositorio de material didáctico para los alumnos de la Facultad de Informática de la Universidad Complutense de Madrid, es una aplicación web cuyo principal objetivo es el de facilitar a los alumnos el acceso a material educativo que les ayude en sus estudios. A diferencia de otros recursos similares, este repositorio tiene la peculiaridad de que son sus propios usuarios lo que, mediante sus propios envíos, se encargan de actualizar y de controlar sus contenidos. Para su implementación hemos utilizado uno de los repositorios de código abierto más importantes y usados en el ámbito académico, DSpace, y lo hemos modificado y personalizado hasta que le hemos dotado de una identidad propia y original. Nuestro objetivo principal ha sido el de crear una aplicación potencialmente útil para la Facultad de Informática y fácilmente configurable para que sirva a los intereses de otras universidades que lo necesiten. [ABSTRACT] The repository of teaching materials for students from the Facultad de Informática of the Universidad Complutense de Madrid, is a web application whose main purpose is to provide students with access to educational materials and help them in their studies. Unlike other similar resources, this repository has the peculiarity that the very users of the application are the ones in charge of updating and controlling their content through their own submits. For its implementation we have used one of the most important and most used in the academic field open source repositories, DSpace, and we have modified and customized it until we gave it an identity of its own. Our main goal has been creating a potentially useful application for the Facultad de Informática and easily configurable to serve similar purposes for other universities which may need it

    Fast determination of a novel iron chelate prototype used as a fertilizer by liquid chromatography coupled to a diode array detector

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    The environmental risk of the application of synthetic chelates has favored the implementation of new biodegradable ligands to correct Fe-deficient plants. This study developed and validated an analytical method for determination of a new prototype iron chelate-Fe(III)-benzeneacetate, 2-hydroxy-α-[(2-hydroxyethyl)amino]-(BHH/Fe3+) based on liquid chromatography with diode array detection, as a potential sustainable alternative. Chromatographic analysis was performed on a LiChrospher RP-18 in reverse-phase mode, with a mobile phase consisting of a mixture of acetonitrile (solvent A) and sodium borate buffer 0.20 mM at pH = 8 (solvent B) at a flow rate of 1.0 mL/min in isocratic elution mode. This method was fully validated and found to be linear from the limit of quantification (LOQ) to 50 mg/L and precise (standard deviation below 5%). The proposed method was demonstrated to be selective, precise, and robust. The developed methodology indicated that it is suitable for the quantification of iron chelate BHH/Fe3+The authors gratefully acknowledge the financial support by the Spanish Ministry of Economy and Competitiveness Project RTI2018-096268-B-I00, and the Comunidad de Madrid (Spain) and Structural Funds 2014−2020 (ERDF and ESF) project AGRISOST-CM S2018/BAA-433

    Gingival hyperplasia as an early manifestation of acute myeloid leukemia. A retrospective review

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    We study the prevalence of acute myeloid leukemia (AML) among patients with severe gingival enlargement. We retrospective reviewed the clinical records of patients with severe gingival enlargement, between 2011 and 2018. The Saxer and Mühlemann index were used to measure inflammation and gingival bleeding. The degree of dental mobility was measured by the Nyman and Lindhe technique. A correlation analysis was carried out to test whether there were any associations among the different variables. In the sample of 117 patients the mean gingival bleeding index was ?3 and the degree of dental mobility ?2.3. 1.7% of patients, with severe gingival hyperplasia were diagnosed with AML. We found a significant association between gingival bleeding and aging (p<0.001) and a trend (0.54) between bleeding and suffering from AML. Severe gingival enlargement, abundant gingival bleeding, and dental mobility could be early manifestations of a blood dyscrasia

    Epidemiological survey on third molar agenesis and facial pattern among adolescents requiring orthodontic treatment

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    The aim of this study was to determine the association between facial pattern according to Ricketts cephalometric analysis, and prevalence of third molar agenesis, taking subject age and gender as control variables. An epidemiological survey was conducted based on a sample of 224 candidates for orthodontic treatment aged 12 to 24 (n=224). Third molar agenesis was recorded using Ricketts cephalometric analyses of lateral teleradiographs and panoramic radiographs. The risk for agenesis was predicted considering the 5 Vert Index parameters (facial axis, facial depth, mandibular plane angle, lower facial height and mandibular arch), facial type (brachyfacial, mesofacial, dolichofacial) and sociodemographic variables (age and sex), using odds ratio (OR) calculated by logistic regression. Third molar agenesis was observed in 25% of the sample. Risk for agenesis is significantly determined by sociodemographic factors (age, OR: 1.2), cephalic patterns (mesofacial vs dolichofacial, OR:4.3; and brachyfacial vs dolichofacial OR: 3.2) and cephalometric patterns (facial axis, OR: 0.8; lower facial height, OR: 0.8; and mandibular plane angle, OR:0.9). Facial parameters (facial axis, lower facial height, and mandibular plane angle) proved to be strong predictors of the risk for third molar agenesis, the prevalence of agenesis being significantly lower in dolichofacial individuals

    Clinical and sociodemographic predictors of oral pain and eating problems among adult and senior Spaniards in the national survey performed in 2010

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    Background: Pain and chewing difficulties have been identified as the strongest predictors of oral disadvantage. The aim of this study is to analyze and quantify the sociodemographic, behavioural and clinical factors modulating the oral pain and eating difficulties reported by Spanish adults and elderly Spanish people in the last National Oral Health Survey performed in 2010. Material and Methods: Data concerning pain and chewing difficulties were acquired on a Likert‑scale format from a representative sample of the Spanish general population with ages between 35-44 years (n=391) and 65 - 74 years (n=405). Risk factors were identified using bivariate analysis, after which the crude association between risk factors (sociodemographic, behavioural and clinical) and outcome variables (pain and eating problems) was assessed by adjusted odds ratios, calculated by means of multivariate logistic regression. Results: Eating problems and oral pain were mainly associated with prosthetic and caries treatment needs as clinical predictors, but female sex was also seen to be a relevant and significant risk factor for suffering pain and eating restrictions. Paradoxically, after taking into account all the aforementioned predictors, the adults had an almost two‑fold higher risk of reporting pain or eating difficulties than the elderly subjects. Conclusions: In agreement with the results from the last national oral health survey, prosthetic and caries treatment needs should be considered key factors in determining the oral well - being of the Spanish population. In sociodemographic terms, the women and adults were seen to be at a significantly higher risk of suffering pain and eating restrictions

    Power-Aware Multi-Objective Evolvable Hardware System on an FPGA

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    Dynamic and Partial Reconfiguration (DPR) allows a system to be able to modify certain parts of itself during run-time. This feature gives rise to the capability of evolution: changing parts of the configuration according to the online evaluation of performance or other parameters. The evolution is achieved through a bio-inspired model in which the features of the system are identified as genes. The objective of the evolution may not be a single one; in this work, power consumption is taken into consideration, together with the quality of filtering, as the measure of performance, of a noisy image. Pareto optimality is applied to the evolutionary process, in order to find a representative set of optimal solutions as for performance and power consumption. The main contributions of this paper are: implementing an evolvable system on a low-power Spartan-6 FPGA included in a Wireless Sensor Network node and, by enabling the availability of a real measure of power consumption at run-time, achieving the capability of multi-objective evolution, that yields different optimal configurations, among which the selected one will depend on the relative “weights” of performance and power consumption

    Influence of seasonal factors in the earned value of construction

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    [EN] The objectives in each construction process can be multiple. However, the constructions have to be carried out under some restrictions concerning price and terms. They constitute some strategic and interdependent goals. In other words, ¿time is money¿. Several papers support that seasonal effects influence the execution rate of construction. Thus, most of them try to improve the forecasts by evaluating and joining them to the planning, although always measuring their influence indirectly. In this paper, we suggest a methodology to directly measure the influence of the seasonal factors as a whole over the earned value of construction. Additionally, we apply it to a certain case study regarding the subsidised housing of public promotion in the Castilla-La Mancha region (Spain). It is worth mentioning that our results are clarified: we have calculated the average monthly production for each month a year with respect to the annual monthly mean. Moreover, the differences regarding the average monthly production we have contributed are quite significant, and hence they have to be taken into account for each earned value forecast so that a project becomes reliable.The authors would like to thank Gicaman SA, Eres SA, and Urvial SA (construction companies) by the cession of their outcome data corresponding to 161 public promotions that gave rise to 5,319 subsidised housing.Ruiz-Fernández, JP.; Benlloch Marco, J.; López, MA.; Valverde-Gascueña, N. (2019). Influence of seasonal factors in the earned value of construction. Applied Mathematics and Nonlinear Sciences. 4(1):21-34. https://doi.org/10.2478/AMNS.2019.1.00003S213441Koehn, E., & Brown, G. (1985). Climatic Effects on Construction. Journal of Construction Engineering and Management, 111(2), 129-137. doi:10.1061/(asce)0733-9364(1985)111:2(129)El-Rayes, K., & Moselhi, O. (2001). Impact of Rainfall on the Productivity of Highway Construction. Journal of Construction Engineering and Management, 127(2), 125-131. doi:10.1061/(asce)0733-9364(2001)127:2(125)Kenley, R., & Wilson, O. D. (1989). A construction project net cash flow model. Construction Management and Economics, 7(1), 3-18. doi:10.1080/01446198900000002Skitmore, M. (1992). Parameter prediction for cash flow forecasting models. Construction Management and Economics, 10(5), 397-413. doi:10.1080/01446199200000038Chan, D. W. M., & Kumaraswamy, M. M. (1995). A study of the factors affecting construction durations in Hong Kong. Construction Management and Economics, 13(4), 319-333. doi:10.1080/01446199500000037Kaka, A. P., & Price, A. D. F. (1993). Modelling standard cost commitment curves for contractors’ cash flow forecasting. Construction Management and Economics, 11(4), 271-283. doi:10.1080/01446199300000027Blyth, K., & Kaka, A. (2006). A novel multiple linear regression model for forecasting S‐curves. Engineering, Construction and Architectural Management, 13(1), 82-95. doi:10.1108/09699980610646511Khosrowshahi, F., & Kaka, A. P. (2007). A Decision Support Model for Construction Cash Flow Management. Computer-Aided Civil and Infrastructure Engineering, 22(7), 527-539. doi:10.1111/j.1467-8667.2007.00508.

    Safety and Efficacy of a New Synthetic Material Based on Monetite, Silica Gel, PS-Wallastonite, and a Hydroxyapatite Calcium Deficient: A Randomized Comparative Clinic Trial

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    Background and Objectives: Maxillary bone defects related to post-extraction alveolar ridge resorption are usual. These defects may lead to failure in further surgical implant phases given the lack of bone volume to perform the dental implant. The objective of this clinical assay was to evaluate the safety and efficacy of an experimental synthetic bone substitute in the preservation of post-extraction maxillary alveoli. Materials and Methods: 33 voluntary patients who had at least one maxillary premolar tooth that was a candidate for exodontia (n = 39) and subsequent implant rehabilitation participated. The regenerated alveoli were monitored by means of periodic clinical examinations (days 9 ± 1, 21 ± 4, 42 ± 6, and 84 ± 6), measuring the height and width of the alveolar crest (days 0 and 180 ± 5), measurement of radiodensity using tomographic techniques (days 0–5 and 175 ± 5), and histological examination of biopsies collected at 180 ± 5 days. Results: No significant differences were observed during the entire follow-up period between the two groups with respect to the safety variables studied. A variation in width of −0.9 ± 1.3 mm and −0.6 ± 1.5 mm, and a variation in height of −0.1 ± 0.9 mm and −0.3 ± 0.7 mm was observed for experimental material Sil-Oss® and Bio-Oss®, respectively. The radiodensity of the alveoli regenerated with the experimental material was significantly lower than that corresponding to Bio-Oss®. However, the histological study showed greater osteoid matrix and replacement of the material with newformed bone in the implanted beds with the experimental material. Conclusions: Both materials can be used safely and proved equally effective in maintaining alveolar flange dimensions, they are also histologically biocompatible, bioactive and osteoconductive. The experimental material showed the advantage of being resorbable and replaced with newformed bone, in addition to promoting bone regeneration
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