175 research outputs found

    Plasticidad fenotípica de Pinus pinaster frente a la disponibilidad de nutrientes

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    7 páginas, 4 figuras, 1 tabla -- Comunicación presentada en la IV Reunión sobre Genética Forestal (2008), celebrada en Pontevedra entre el 27 y el 29 de junio de 2007.En tres ensayos factoriales familia x fertilización situados en sitios de baja fertilidad en el Sur de Galicia se analizó la plasticidad fenotípica en el desarrollo y la variación genética en plasticidad en familias de medios hermanos de Pinus pinaster. La autocorrelación espacial que presentaron las variables de estudio invalidaron las técnicas de análisis convencional, siendo necesario ajustar los datos espacialmente mediante técnicas de geoestadística. En las tres parcelas se encontró variación genética en el crecimiento de la población de estudio además de plasticidad fenotípica frente a la disponibilidad de nutrientes en el gradiente de fertilización ensayado. En concordancia con estudios nutricionales previos en Galicia, la fertilización resultó ser beneficiosa para el crecimiento de las plantas. También se encontró variación genética en la plasticidad en todas las parcelas, lo que indica que existen variaciones genéticas en la eficacia nutricional entre las familias estudiadas. Sin embargo, la interacción fertilización x sitio, familia x sitio y familia x fertilización x sitio muestra un patrón de respuesta complejo.Este trabajo se ha realizado al amparo del Proyecto de Investigación INIA-RTA05-173.Peer reviewe

    Phenotypic plasticity of maritime pine to insect herbivory

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    PósterPeer Reviewe

    Genetic variation and phenotypic plasticity of nutrient re-allocation and increased fine root production as putative tolerance mechanisms inducible by methyl jasmonate in pine trees

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    1. Plant plastic responses to herbivore damage may include rapid, active reallocation of plant resources to reduce the impact of herbivory on future plant fitness. However, whether these inducible tolerance responses can be extended to pine trees and how these responses could be modulated by genetic and environmental factors remains unclear.2. Biomass allocation and phosphorus (P) and nitrogen (N) concentrations in above- and belowground tissues were measured in Pinus pinaster juveniles belonging to 33 open-pollinated families grown under two P availabilities (P-deficient and complete fertilization). Measurements were taken 15 days after half of the plants received a foliar spray treatment of 22 mmol L)1 methyl jasmonate (MJ) to simulate above-ground herbivore attack.3. Simulated above-ground herbivory promoted a strong preferential allocation of biomass below ground in the form of fine roots, leading to an almost two-fold increase in fine root biomass in MJ-treated plants and a significant reduction in above-ground tissues and coarse roots. In addition, MJ signalling increased P andN concentrations in the shoots while reducing (P) or maintaining (N) concentrations in the roots. These results suggest that induced resource sequestration is not a generalized strategy in this pine species. Fine root biomass and concentration of N and P in plant tissues showed additive genetic variation, but responses to MJ signalling did not vary among families. Allocation of biomass to fine roots was not affected by P availability, whereas allocation of P to the shoot was more intense under complete fertilization.4. Synthesis: Two new putative tolerance mechanisms inducible by MJ signalling may help to minimize the impact of above-ground herbivore damage on the future fitness of young pine trees by (i) allocation of carbon to fine roots, this appeared to be a generalized strategy with weak environmental modulation and (ii) reallocation of P and N from roots to shoots, which was largely affected by P availability, and thus susceptible to greater phenotypic variation in heterogeneous environments. We provide evidence that changes in tolerance-related traits are rapidly inducible by herbivory cues in this pine species. These results should be integrated with induced resistance responses to fully understand the costs and benefits associated with induced responses to herbivory.This research was supported by the grants AGL2010-18724, RTA07-100, PSE310000. LS and XM received financial support from DOC-INIA and PREDOC-INIA grant programs respectively.INIAPeer Reviewe

    Cognitive reserve mediates the severity of certain neuropsychological deficits related to cocaine use disorder

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    Introduction: The concept of cognitive reserve (CR) is being considered in the field of substance use disorder (SUD) by observing that there are individuals whose brain alterations are not related to the cognitive symptomatology they present. Aims: Our aims were to characterise the possible neuropsychological deficits in a sample of subjects with SUD compared to a control group and to determine whether the degree of CR is a mediator in the cognitive functioning of these patients. Methods: To perform these objectives, the study involved a sample of subjects with SUD in outpatient treatment and a control group. A CR questionnaire and a comprehensive neuropsychological assessment were administered, and we also collected data related to drug consumption and psychological well-being. Results: The SUD group showed poorer performance compared to the control group in several cognitive domains (attention, declarative memory, executive functions and emotional perception), as well as in psychological comfort. Interestingly, we observed that the deficits found in attention, declarative memory and executive functions were mediated by the CR level of the participants, an effect that we did not observe in the rest of the variables registered. Conclusion: Our results suggest that long-term drug consumption leads to cognitive deficits and affects the psychological well-being of the subjects. Moreover, the CR should be taken into account during the assessment and rehabilitation of patients with SUD due to its protective role against certain neuropsychological deficits.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Nutritional status and genetic variation in the response to nutrient availability in Pinus pinaster. A multisite field study in NW Spain

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    The low nutrient availability of the acidic and sandy soils of Galicia (Northwest Spain) is probably the main environmental factor limiting forest primary productivity in the area. These particular edaphic conditions could have imposed selective pressures on maritime pine populations leading to specific local adaptations. We first assessed the nutritional status of 22 young contemporary Pinus pinaster plantations in Northwest Spain, and then analysed the response to fertilization in three family × fertilization trials, and how this response varied across sites and genotypes. Growth of P. pinaster in Northwest Spain appeared to be largely limited by nutrient availability, where most of the plantations showed severe nutrient deficiencies, especially in P and Mg. According to these deficiencies, a strong positive response to nutrient additions was observed in the three trials, with height increments of up to 30% compared with the unfertilized control. However, the response to fertilizers was very variable from site to site, and in some cases did not agree with the foliar nutritional diagnosis. The response to fertilization was also significantly affected by pine genotype, suggesting that the plastic response to nutrient additions within each environment was under genetic control. However, the family response to nutrient availability was not consistent across sites, and no significant differences among families were observed for the RDPI plasticity index – a single index that summarizes the phenotypic change in multiple environments – when analysed across environments. The strong environmental component modulating phenotypic responses to fertilization could impose an important obstacle to evolve specific adaptations to the local edaphic conditions, as well as to artificially select genotypes adapted to different environments and silviculture regimes.This research was funded by the INIA projects RTA05-173 and RTA07-100.Peer reviewe

    Genetics, phosphorus availability, and herbivore-derived induction as sources of phenotypic variation of leaf volatile terpenes in a pine species

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    Oleoresin produced and stored in pine tree leaves provides direct resistance to herbivores, while leaf volatile terpenes (LVT) in the resin are also powerful airborne infochemicals. Resin concentration and profile show considerable spatial and temporal phenotypic variation within and among pine populations. LVT biochemistry is known to be under genetic control, and although LVT should be plastic to diverse abiotic and biotic environmental factors such as nutrient availability and herbivore attack, little is known about their relative contributions and interactive effects. The aim of this paper was to clarify whether reduced phosphorus availability could increase the LVT concentration and affect the expression of herbivore-derived induced defences, and how plasticity would contribute to the phenotypic variation of LVT. The constitutive and methyl-jasmonate (MeJa) induced LVT concentration and profile were analysed in 17 half-sib Pinus pinaster families growing under two levels of P-availability (complete and P-limited fertilization). Individual terpene concentrations showed large additive genetic variation, which was more pronounced in the control than in MeJa-induced pines. MeJa application did not affect the LVT concentration, but significantly modified the LVT profile by depleting the α-pinene content and reducing the sesquiterpene fraction. Low P-availability strongly reduced plant growth and foliar nutrient concentrations, but did not affect LVT concentration and profile, and did not interact with MeJa-induction. Results indicate a strong homeostasis of LVT concentration to P-availability, and minor changes in the LVT profile due to MeJa-induction. Genetic variation appears to be the main source of phenotypic variation affecting the LVT concentration in this pine species.This work was supported by the Spanish Instituto Nacional de Investigación y Tecnología Agraria y Agroalimentaria (grant number INIA-RTA07-100; and DOC-INIA and PREDOC-INIA fellows for LS and XM, respectively); the Spanish Agency of Science and Technology (grant numbers CGL2006-04025/BOS, CGL2010-17172, and CSD2008- 00040 for JP and JL; and AGL2010-18724 and PSE310000 for RZ and LS); and the Catalonian Government (grant number SGR 2009-1458).Peer reviewe

    Densidad y área de los canales resiníferos de "Pinus pinaster" ante tratamientos de fertilización, y su relación con la defensa ante "Hylobius abietis"

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    6 páginas, 3 tablas -- Actas de la I Reunión sobre Sanidad Forestal celebrada en Palencia el 24 y 25 de septiembre de 2007.Las coníferas poseen una estructura de canales resiníferos que actúa como defensa contra el ataque de insectos y patógenos. Varios autores han observado que un aumento en la disponibilidad de nutrientes puede alterar el reparto de energía en las plantas, en detrimento de los sistemas defensivos. El presente estudio tiene como objetivo determinar el efecto de la fertilización de establecimiento sobre el desarrollo del sistema de canales resiníferos en Pinus pinaster. Mediante histología en brinzales de 3 savias sometidos a dos ensayos familia x fertilización se cuantificó la densidad y el área de los canales resiníferos del floema y del xilema tanto en el tallo principal como en ramas laterales en dos ensayos familia x fertilización. Se observó un efecto significativo de la fertilización en el desarrollo de los canales resiníferos del floema (p<0,05), con valores de 0,45 y 0,36 canales.mm-2 para brinzales no fertilizados y sí fertilizados, respectivamente. Este efecto no se observó en las variables del xilema. La densidad de canales resiníferos en el xilema fue significativamente diferente entre las dos parcelas estudiadas, siendo mayor en la atacada por el curculiónido Hylobius abietis. Por último, la relación tallo-rama de las variables cuantificadas no fue lo suficientemente consistente como para utilizar los canales en ramas de P. pinaster como indicadores de los canales en el tronco principal.Este trabajo se ha realizado bajo financiación del proyecto INIA-RTA05-173.Peer reviewe

    INFORMATION TECHNOLOGIES APPLIED TO ENGINEERING EDUCATION

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    To develop this article, a documentary review of the elaboration and production of research works related to the study of Information Technologies and their application in Engineering Education was carried out &nbsp;in order to know through a bibliometric study the main characteristics of 2159 publications registered in Scopus database during the period 2018-2022 at the Latin American level.&nbsp; The results of&nbsp; this database were organized in graphs and figures categorizing the&nbsp; information by variables such as Year of Publication, Country of Origin and Area of Knowledge which allowed to identify through a qualitative analysis, the position of different authors against the proposed theme.&nbsp; The main findings found through this research was that Brazil stood out for having the highest scientific production, leading the list with 621 publications.&nbsp; Likewise, the Area of Knowledge that made the greatest contribution to the construction of bibliographic material related to the study of the variables was engineering with 2159 published documents

    Implementation of Band-to-Band Tunneling Phenomena in a Multisubband Ensemble Monte Carlo Simulator: Application to Silicon TFETs

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    TFETs are in the way to become an alternative to conventional MOSFETs due to the possibility of achieving low subthreshold swing (SS) combined with small OFF current levels which allows operation at low VDD. In this work, a non-local band–to–band tunneling (BTBT) model has been successfully implemented into a Multi-Subband Ensemble Monte Carlo (MSEMC) simulator and applied to ultra-scaled silicon-based n-type TFETs. We have considered two different criteria for the choice of the tunneling path followed by the carriers when crossing the potential barrier, which leads to different distributions of the generated electron-hole pairs. Subband discretization due to field–induced quantum confinement has been taken into account. TCAD simulations accounting for quantization effects are considered for comparison purposes providing very accurate agreement with MS-EMC results

    Impact of the Trap Attributes on the Gate Leakage Mechanisms in a 2D MS-EMC Nanodevice Simulator

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    From a modeling point of view, the inclusion of adequate physical phenomena is mandatory when analyzing the behavior of new transistor architectures. In particular, the high electric field across the ultra-thin insulator in aggressively scaled transistors leads to the possibility for the charge carriers in the channel to tunnel through the gate oxide via various gate leakage mechanisms (GLMs). In this work, we study the impact of trap number on gate leakage using the GLM model, which is included in a Multi-Subband Ensemble Monte Carlo (MS-EMC) simulator for Fully-Depleted Silicon-On-Insulator (FDSOI) field effect transistors (FETs). The GLM code described herein considers both direct and trap-assisted tunneling. This work shows that trap attributes and dynamics can modify the device electrostatic characteristics and even play a significant role in determining the extent of GLMs.The research leading to these results has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 688101 SUPERAID7
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