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The photosynthesis source-sink relationship in young Pinus canariensis seedlings was modified by stem girdling to investigate sprouting and cambial activity, feedback inhibition of photosynthesis, and stem and root hydraulic capacity. Removal of bark tissue showed a trade-off between sprouting and diameter growth. Above the girdle, growth was accelerated but the number of sprouts was almost negligible, whereas below the girdle the response was reversed. Girdling resulted in a sharp decrease in whole plant transpiration and root hydraulic conductance. The reduction of leaf area after girdling was strengthened by the high levels of abscisic acid found in buds which pointed to stronger bud dormancy, preventing a new needle flush. Accumulation of sugars in leaves led to a coordinated reduction in net photosynthesis (AN) and stomatal conductance (gS) in the short term, but later (gS below 0.07 mol m(-2) s(-1)) AN decreased faster. The decrease in maximal efficiency of photosystem II (FV/FM) and the operating quantum efficiency of photosystem II (?PSII) in girdled plants could suggest photoprotection of leaves, as shown by the vigorous recovery of AN and ?PSII after reconnection of the phloem. Stem girdling did not affect xylem embolism but increased stem hydraulic conductance above the girdle. This study shows that stem girdling affects not only the carbon balance, but also the water status of the plant.

Background Wounds caused by fire, herbivorism, rock impacts, etc. cause the direct loss of photosynthetic, storage and/or vascular tissue. In addition, they may entail other damages, such as desiccation of the exposed internal parts, or become a gateway to infection by fungi and other pathogens. To successfully overcome such injuries, plants must reorganize their meristems or even differentiate new ones, producing new traumatic tissues to cover the wound and restore the vascular connection. Results In this work we analyse the anatomical growth response in conifers after debarking and injuring the vascular cambium, using Pinus canariensis as model species, due to its high wound recovery ability. Conversely to angiosperm woody species, this process is initiated and largely driven by the damaged vascular cambium and not by proliferation in the wound surface. We have detected alterations and switches in the divisions of cambial cells, associated to their position relative to the surface and edges of the wound, resulting in disordered traumatic xylem. We also describe the formation of column-like structures, after girdling, which are in part formed by the proliferation of xylem parenchymatous cells, associated to axial resin ducts. Conclusions Abundant resinosis on the wound surface, typical of conifers, is an efficient barrier against opportunistic fungi, insects, etc. but it also hinders the healing process directly from the surface. Thus, wound closure must be largely carried out from the wound margins, being a much slower process, which very often remains unconcluded for long years. This work also describes for the first time the proliferation of inner parenchymatous cells to form column-like structures, which accelerates wound closure in girdled P. canariensis. Irregularities in the surface of the healing edge or column-like structures result in the production of disordered vascular tissues, compromising their future functionality, and which must be overcome through the fast restoration of the proper polarity in vascular cambium.

Aim of the study: Models that combine parentage analysis from molecular data with spatial information of seeds and seedlings provide a framework to describe and identify the factors involved in seed dispersal and recruitment of forest species. In the present study we used a spatially explicit method (the gene shadow model) in order to assess primary and effective dispersal in Pinus canariensis.Area of study: Pinus canariensis is endemic to the Canary Islands (Spain). Sampling sites were a high density forest in southern slopes of Tenerife and a low density stand in South Gran Canaria. Materials and methods: We fitted models based on parentage analysis from seeds and seedlings collected in two sites with contrasting stand density, and then compared the resulting dispersal distributions.Main results: The results showed that: 1) P. canariensis has a remarkable dispersal ability compared to other pine species; 2) there is no discordance between primary and effective dispersals, suggesting limited secondary dispersal by animals and lack of Janzen-Connell effect; and 3) low stand densities enhance the extent of seed dispersal, which was higher in the low density stand.Research highlights: The efficient dispersal mechanism of P. canariensis by wind inferred by the gene shadow model is congruent with indirect measures of gene flow, and has utility in reconstructing past demographic events and in predicting future distribution ranges for the species.Keywords: Bayesian inference; Canary Islands; gene shadow model; microsatellites; parentage analysis.

In the last five years, sharp increases in the price of natural resins, accompanied by technological advances directed toward mechanization, have made resin tapping a strategic activity for rural development and forest conservation. The resin industry demands more efficient tapping methods and forest management plans as a way to increase competitiveness in a global market. Understanding the effects of environmental conditions on resin yield, especially under the current scenario of climate change, is key to improving techniques and plans in the resin industry. This study aims to evaluate the intra- and inter-annual effects of climate conditions and soil water availability on resin yield in tapped Pinus pinaster stands. The individual resin yield of 26 tapped trees growing at two locations with different stand densities and soil characteristics was measured fortnightly during the tapping season (June to October) for four years. The study was complemented with an analysis of changes in xylem anatomy over the four years, with a focus on axial resin canal traits, including 12 non-tapped trees as controls. Intra-annual variation in resin yield was strongly correlated with temperature, solar radiation, potential evapotranspiration and water deficit. Inter-annual variation in resin yield and resin canal abundance were correlated with temperature and water deficit in spring, but above a certain threshold of cumulated water deficit in summer rainfall favored resin yield. Under adverse climate scenarios where resource optimization is desirable, a reduced tapping season during the warmest months (June-September) would be advisable, assuming a very small production loss. Similarly, in years with a rainy summer and/or dry spring, a slightly longer tapping season could be suggested, as resin yield increases after these events. © 2014 Elsevier B.V.

The aim of this study was to provide new insights into how intraspecific variability in the response of key functional traits to drought dictates the interplay between gas-exchange parameters and the hydraulic architecture of European beech (Fagus sylvatica L.). Considering the relationships between hydraulic and leaf functional traits, we tested whether local adaptation to water stress occurs in this species. To address these objectives, we conducted a glasshouse experiment in which 2-year-old saplings from six beech populations were subjected to different watering treatments. These populations encompassed central and marginal areas of the range, with variation in macro- and microclimatic water availability. The results highlight subtle but significant differences among populations in their functional response to drought. Interpopulation differences in hydraulic traits suggest that vulnerability to cavitation is higher in populations with higher sensitivity to drought. However, there was no clear relationship between variables related to hydraulic efficiency, such as xylem-specific hydraulic conductivity or stomatal conductance, and those that reflect resistance to xylem cavitation (i.e.;ψ12, the water potential corresponding to a 12% loss of stem hydraulic conductivity). The results suggest that while a trade-off between photosynthetic capacity at the leaf level and hydraulic function of xylem could be established across populations, it functions independently of the compromise between safety and efficiency of the hydraulic system with regard to water use at the interpopulation level. © The Author 2014. Published by Oxford University Press. All rights reserved.

Introduccion se describen las caracteristicas clinicas, funcionales y socioeconomicas de un grupo de pacientes que precisan atencion para cuidados domiciliarios. Se evalua la repercusion en el cuidador principal del hecho de cuidar. Material y metodo estudio descriptivo transversal. Marco comunitario (Centro de Salud San Agustin de Burgos). Se recogen datos de la historia clinica del paciente y se aplica un cuestionario especifico a un grupo de cuidadores. Analisis estadistico: SPSS version 10.0. Resultados Pacientes 88 casos (63,6% mujeres), 93,2% mayores de 65 anos. Mas del 50% con dependencia grave o total. La mayoria vive en domicilio propio. El 21,6% de las viviendas no dispone de ascensor. Cuidadores edad media ± desviacion estandar de 62,0 ± 14,9 anos; el 84% eran mujeres (hija en el 56% de los casos, conyuge en el 36%). Dos terceras partes estan casados. Principales quejas del cuidador: falta de tiempo libre (60%), restriccion en su vida anterior (84%), cambio de proyectos personales (66%). Tienen lumbalgias (64%) y algias musculares (40%), ansiedad (36%), depression (44%) y sindrome de estres del cuidador (36%). Mas estres en enfermos terminales, enfermedad mental y deficit visuales y auditivos. Menor necesidad de consultas medicas a mayor tiempo de inclusion en el programa. Conclusiones el paciente inmovilizado tipo en nuestro medio es una mujer anciana, viuda, que vive en su domicilio, cuidada por una hija/o, con escaso apoyo social, importante comorbilidad y polimedicada. La mayoria de los cuidadores son mujeres casadas de mediana edad, con gran prevalencia de ansiedad/depresion, y pueden estar infratratados.

A heteroblastic (or vegetative phase) change is an abrupt manifestation in the general heteroblastic development during the ontogeny of plants. The Canary Island pine undergoes an especially marked and delayed heteroblastic change, including both the formation of secondary needles on dwarf shoots and the onset of preformed growth. To assess genetic and environmental effects on the heteroblastic change in this species, we followed plants from 19 populations at a dry site and a wetter site. Comparing juvenile and adult needles from the same individuals, the adult had a significantly lower rate of water loss and higher leaf mass per area. Pooling data from all seed sources, the heteroblastic change took place when plants reached a critical height, on average, at 4 years of age at the dry site and 1 year earlier at the wet site. Within a subsample of individuals of equal size, mortality was significantly higher in juvenile plants than in mature plants. However, the juvenile phase was longer in plants from dry regions when compared to plants from highly productive, wet regions. This apparent contradiction might be explained through differential resource allocation and the cost of sclerophylly and resprouting ability. Considering the life strategy of the Canary Island pine, we interpret the prolonged juvenile phase as an unavoidable trade-off for the high tolerance of adults to harsh environments.

El estudio taxonómico de la estructura de los portales periodísticos y el análisis de la frecuencia de aparición de sus componentes —productos informativos, productos documentales y servicios de valor añadido— han fijado el actual estado de la cuestión sobre su desarrollo. La minería de datos es una tecnología que permite identificar tendencias y patrones seguidos en ese desarrollo a partir de la base de conocimientos aportada por los trabajos anteriormente llevados a cabo, permitiendo recuperar información suplementaria a la ya explicitada. Aplicando un análisis multivariante a la matriz de portales periodísticos y elementos componentes, se obtiene una serie de agrupamientos que permitirán determinar qué portales marcan la tendencia a seguir, al mismo tiempo que se aporta información adicional sobre sus grupos de comunicación y sobre el medio origen del que proceden —prensa, radio, televisión o Internet—. El positivo resultado de esta investigación verifica su viabilidad, vaticinando su posible adaptación a otros tipos de portales desarrollados en la web

Se analizan los elementos que componen los portales periodísticos de radio y televisión españoles, identificando su estructura y comparando su oferta de productos y servicios, según el medio de comunicación. Se comparan los resultados con el modelo de portal periodístico de prensa desarrollado por el grupo de investigación del autor, de manera que se puedan esbozar las tendencias actuales de productos y servicios presentes en el periodismo en línea español, construyendo un modelo general de referencia para cualquier tipo de portal periodístico. (A)

Propuesta de clasificación de los servicios de valor añadido (SVA) de los portales periodísticos españoles a partir del análisis de un total de diecisiete portales, los de los rotativos nacionales y una representación de la prensa regional. Se identificaron ocho categorías de SVA: acceso a la información, interactivos, participación, multimedia, personalizados, entretenimiento, comerciales y Complementarios. Los SVA más consolidados son los pertenecientes a las categorías de acceso a la información e interactivos, seguidos muy de cerca por los de participación. Los portales periodísticos que destacan en la categoría de SVA de acceso a la información son los pertenecientes a los diarios El Mundo, El País y La Verdad. En el caso de los SVA interactivos sobresale ABC y Marca, y con respecto a los SVA de participación destaca La Vanguardia. (A)

Stem respiration plays a role in species coexistence and forest dynamics. Here we examined the intra- and inter-specific variability of stem CO2 efflux (E) in dominant and suppressed trees of six deciduous species in a mixed forest stand: Fagus sylvatica L., Quercus petraea [Matt.] Liebl, Quercus pyrenaica Willd., Prunus avium L., Sorbus aucuparia L. and Crataegus monogyna Jacq. We conducted measurements in late autumn. Within species, dominants had higher E per unit stem surface area (Es ) mainly because sapwood depth was higher than in suppressed trees. Across species, however, differences in Es corresponded with differences in the proportion of living parenchyma in sapwood and concentration of non-structural carbohydrates (NSC). Across species, Es was strongly and NSC marginally positively related with an index of drought tolerance, suggesting that slow growth of drought-tolerant trees is related to higher NSC concentration and Es . We conclude that, during the leafless period, E is indicative of maintenance respiration and is related with some ecological characteristics of the species, such as drought resistance; that sapwood depth is the main factor explaining variability in Es within species; and that the proportion of NSC in the sapwood is the main factor behind variability in Es among species.

Water stress (WS) slows growth and photosynthesis (A(n)), but most knowledge comes from short-time studies that do not account for longer term acclimation processes that are especially relevant in tree species. Using two Eucalyptus species that contrast in drought tolerance, we induced moderate and severe water deficits by withholding water until stomatal conductance (g(sw)) decreased to two pre-defined values for 24 d, WS was maintained at the target g(sw) for 29 d and then plants were re-watered. Additionally, we developed new equations to simulate the effect on mesophyll conductance (g(m)) of accounting for the resistance to refixation of CO(2). The diffusive limitations to CO(2), dominated by the stomata, were the most important constraints to A(n). Full recovery of A(n) was reached after re-watering, characterized by quick recovery of gm and even higher biochemical capacity, in contrast to the slower recovery of g(sw). The acclimation to long-term WS led to decreased mesophyll and biochemical limitations, in contrast to studies in which stress was imposed more rapidly. Finally, we provide evidence that higher gm under WS contributes to higher intrinsic water-use efficiency (iWUE) and reduces the leaf oxidative stress, highlighting the importance of gm as a target for breeding/genetic engineering.

Summary Bending of trees causes a transient hydraulic overpressure signal that propagates rapidly along the vascular system in planta. This may be a mechanobiological remote signalling of the mechanical stress., When tree stems are mechanically stimulated, a rapid long-distance signal is induced that slows down primary growth. An investigation was carried out to determine whether the signal might be borne by a mechanically induced pressure pulse in the xylem. Coupling xylem flow meters and pressure sensors with a mechanical testing device, the hydraulic effects of mechanical deformation of tree stem and branches were measured. Organs of several tree species were studied, including gymnosperms and angiosperms with different wood densities and anatomies. Bending had a negligible effect on xylem conductivity, even when deformations were sustained or were larger than would be encountered in nature. It was found that bending caused transient variation in the hydraulic pressure within the xylem of branch segments. This local transient increase in pressure in the xylem was rapidly propagated along the vascular system in planta to the upper and lower regions of the stem. It was shown that this hydraulic pulse originates from the apoplast. Water that was mobilized in the hydraulic pulses came from the saturated porous material of the conduits and their walls, suggesting that the poroelastic behaviour of xylem might be a key factor. Although likely to be a generic mechanical response, quantitative differences in the hydraulic pulse were found in different species, possibly related to differences in xylem anatomy. Importantly the hydraulic pulse was proportional to the strained volume, similar to known thigmomorphogenetic responses. It is hypothesized that the hydraulic pulse may be the signal that rapidly transmits mechanobiological information to leaves, roots, and apices.

Dutch elm disease (DED) is a vascular wilt disease that causes the occlusion and cavitation of xylem vessels. Therefore,it is hypothesized that those elms that are less vulnerable to cavitation by drought might be more resistant to DED. Totest this hypothesis, the relationship between xylem vulnerability to cavitation and susceptibility to DED was examinedin progenies of crosses between susceptible and resistant individuals of Ulmus minor. Hydraulic conductivity and xylemvulnerability curves were evaluated and anatomical features such as vessel size, length and grouping were measured.Next, elms were inoculated with Ophiostoma novo-ulmi, the cause of DED, and pre-dawn and midday waterpotentials, stomatal conductance and wilting percentages were assessed. Progenies of R 9 R crosses showed signifi-cantly lower mean wilting percentages (30–50%) than the progeny of S 9 S crosses (75%). Fifty percent conductivityloss was reached at c. 1 MPa, pointing out a high vulnerability of this species to drought-induced cavitation. Crownwilting percentage as a result of inoculation and xylem vulnerability to cavitation by water stress did not show anysignificant correlation. Nevertheless, significant differences in theoretical hydraulic conductivity and vessel size parame-ters (diameter, length and size distributions) were found among the tested progenies. Susceptible trees had significantlywider and longer vessels. Xylem structure of resistant elms seems to restrict pathogen spread rather than preventcavitation.Keywords: Dutch elm disease, elm breeding, Ulmus minor, water stress, wood anatomy, xylem vulnerability curves

En los últimos años las Administraciones Públicas vienen desarrollando continuos esfuerzos en pos de la modernización, aunque pocas veces se aborda con detenimiento la problemática de la gestión de los documentos administrativos. Con el objeto de promover una normalización de los procedimientos administrativos, introducimos la idea de utilizar el tesauro como instrumento para la gestión de esta documentación, medio que nos permitirá alcanzar dos objetivos fundamentales: una consistente normalización terminológica y, por consiguiente, una adecuada recuperación de la información dentro de un entorno relacional. Presentamos la experiencia desarrollada en el seno del Archivo Forestal de la Dirección General del Medio Natural de la Consejería de Medio Ambiente, Agricultura y Agua de la Comunidad Autónoma de la Región de Murcia, resaltando la singular presencia del empleo de este lenguaje documental en un contexto tan poco común. (Autor)

The apparent molecular polarizations at infinite dilution, P2∞, molecular refractions, RD, dipole moments, µ2, polarizabilities, α, and partial molar volumes, V 02,m, of 1,3-benzothiazole and some derivatives at position two or three, have been determined from relative permittivity, density and refractive index measurements in n-hexane or 1,4-dioxane solutions at 25 °C.The RD and V 02,m values correlate well for all substances studied, independently of the solvent used. The P2∞ values appear to be slightly dependent on the solvent showing the presence of specific interactions as hydrogen bond.The apparent relative permittivity, e2′, and the refraction index extrapolated at the IR region, nIR, have been estimated for all solutes. In the case of 1,3-benzothiazole and its 2-methyl derivative, these results have been compared with the relative permittivities measured at 25 °C at low and high frequencies, respectively, by the Cole–Cole dynamic method, showing a good agreement.The apparent dipole moments and their changes with the corresponding substituent group have been determined by three different methods. From the measurement of dipole moment it has been unambiguously established that the tautomeric equilibrium between 2-mercapto-1,3-benzothiazole and 2-thioxo-3H-1,3-benzothiazole is strongly displaced to the latter. Changes in the apparent molar solution volumes and apparent molar polarizations of the solutes in the considered solvents are qualitatively discussed.Comparison between pKa values reported in the literature and the corresponding µ values for free base benzothiazole derivatives have been carried out as well as the appropriate qualitative discussion.

Summary Activating and inhibitory killer immunoglobulin-like receptors (KIR) and their ligands HLA-Bw4 (loci A and B) were studied by way of establishing whether they can contribute to protection against HIV-1 infection in highly exposed and persistently seronegative (HESN) patients. Twenty-three HIV-1 serodiscordant heterosexual couples, 100 HIV-1+ patients and 200 healthy individuals were included in this retrospective case–control study. HLA typing was performed by means of PCR followed by sequence-specific oligonucleotide probe reverse hybridization. KIR3DL1 and KIR3DS1 were studied by PCR sequence-specific primers. The frequency of KIR3DS1(3DS1/3DL1)-Bw4 combination was significantly higher in HESN patients versus the discordant couples (P = 0·0003) and HIV-1+ patients (P = 0·0001). Conversely, the KIR3DL1/KIR3DL1 homozygosity was significantly decreased in HESN patients versus the discordant couples (P = 0·00003), and HIV-1+ patients (P = 0·00066). The frequency of HLA-A*32 and HLA-B*44 was higher in HESN versus their discordant couples (P = 0·009; P = 0·049), and HIV-1+ patients (P = 0·00002; P = 0·0001). This had greater significance in combination with KIR3DS1 (3DS1/3DL1). KIR3DS1(3DS1/3DL1) could have a greater effect on protection against HIV-1 infection in HESN patients when bound to a specific HLA allele, in this case HLA-A*32 and HLA-B*44, both Bw4 alleles. The differences probably arise both in the HLA alleles and in the subtypes of KIR receptors depending on the ethnic group studied.

[Background and Aims] It is widely accepted that hydraulic failure due to xylem embolism is a key factor contributing to drought-induced mortality in trees. In the present study, an attempt is made to disentangle phenotypic plasticity from genetic variation in hydraulic traits across the entire distribution area of a tree species to detect adaptation to local environments., [Methods] A series of traits related to hydraulics (vulnerability to cavitation and hydraulic conductivity in branches), growth performance and leaf mass per area were assessed in eight Pinus canariensis populations growing in two common gardens under contrasting environments. In addition, the neutral genetic variability (FST) and the genetic differentiation of phenotypic variation (QST) were compared in order to identify the evolutionary forces acting on these traits., [Key Results] The variability for hydraulic traits was largely due to phenotypic plasticity. Nevertheless, the vulnerability to cavitation displayed a significant genetic variability (approx. 5 % of the explained variation), and a significant genetic × environment interaction (between 5 and 19 % of the explained variation). The strong correlation between vulnerability to cavitation and survival in the xeric common garden (r = –0·81; P < 0·05) suggests a role for the former in the adaptation to xeric environments. Populations from drier sites and higher temperature seasonality were less vulnerable to cavitation than those growing at mesic sites. No trade-off between xylem safety and efficiency was detected. QST of parameters of the vulnerability curve (0·365 for P50 and the slope of the vulnerability curve and 0·452 for P88) differed substantially from FST (0·091), indicating divergent selection. In contrast, genetic drift alone was found to be sufficient to explain patterns of differentiation for xylem efficiency and growth., [Conclusions] The ability of P. canariensis to inhabit a wide range of ecosystems seemed to be associated with high phenotypic plasticity and some degree of local adaptations of xylem and leaf traits. Resistance to cavitation conferred adaptive potential for this species to adapt successfully to xeric conditions., We are grateful to the Canary Islands Government, the Cabildos of Tenerife and Gran Canaria and the National Park of Caldera de Taburiente for long-standing support in the study of Canary Island pine. We thank all people involved in the plantation and measurements of the common gardens and to Christian Bodet and Pierre Conchon for their assistance with the Cavitron. R.L. was supported by a González Esparcia fellowship during her stay in Clermont-Ferrand. This work was supported by the Spanish Ministry of Science in the Project AGL2009-10606 (VULCAN).

Antitachycardia pacing (ATP) fails to terminate 5% to 25% of ventricular tachycardias (VTs) occurring in implantable cardioverter-defibrillator patients. We speculated that small fluctuations in VT cycle length (CL) may be related to the efficacy of subsequent ATP.The purpose of this study was to determine the relationship between the R-R variations of the last 12 R-R intervals before ATP and the efficacy of the first ATP attempt.We studied 551 VTs (CL 329±35 ms) occurring in 67 patients. We also analyzed the percentage of variation (P-RR), which was calculated by dividing the mean difference between each R-R interval and the next one by the CL (×100), and the acceleration index (AI), which was calculated by dividing the CL of the first 6 R-R intervals by the CL of the next 6.The effectiveness of the first ATP therapy was 81%, being higher in VTs with AI1 (85% vs 64%; P.001). After classifying the events according to the tertiles of P-RR, ATP efficiency was better in higher values of P-RR (VTs with AI1): 99% (third tertile) vs 85% (second tertile) vs 76% (first tertile), P.001; and for VTs with AI≥1: 94% vs 68% vs 42% (P.001). By logistic regression, P-RR (%; odds ratio 2.37; P.001), and AI1 (odds ratio 4.17; P.001) were found to be independent predictors of successful first ATP attempts.Small changes in CL increase the effectiveness of ATP significantly. VTs with lower degrees of R-R fluctuations, especially when the pattern is a progressive CL shortening, are infrequently terminated by ATP.

Este trabajo recoge una revisión de los servicios ofertados en los portales periodísticos de la prensa española en relación a la oferta del año 2002 cuando se llevó a cabo un primer y exhaustivo análisis taxonómico. Se aplica la misma metodología de estudio, adaptándose los elementos a observar a la evolución advertida a lo largo de estos últimos seis años, marcada por el incremento de consumo de los contenidos suministrados a través de los servicios consolidados de acceso a la información y de los novedosos servicios sociales de participación. Como resultado se constata la importancia de estos servicios, resultantes de la conocida web 2.0, en la expansión de los contenidos digitales de los portales periodísticos y la rápida adaptación de estos medios de comunicación a las necesidades informativas de sus usuarios. ABSTRACT: This work includes a review of the services offered in the newspaper websites of the Spanish press regarding the 2002 offer. It applies the same methodology of study and adapting the elements to watch the evolution warned over the past six years, marked by increased consumption of content through services access to information and innovative social services. The importance of these services is due to the expansion of digital content of the newspaper websites and the rapid adaptation of these media to the information needs of their users and their presentation shapes.

A study was conducted on the variation in growth, biomass, juvenile wood anatomy, and needle morphology of Pinushalepensis Mill. from three Spanish regions of provenance characterized by environmental differences, without the influence of the site factor. Seeds collected from two progenies in each region were planted in a single plot, and the trees were felled at the age of 7 years. The results showed significant differences between provenances, as well as the genetic or environmental influence on the traits analyzed. Trees adapted to moderate summer drought conditions (Inland Catalonia region) are primarily characterized by higher average values for height, diameter, biomass, cell wall thickness, inter-tracheid wall strength, pit membrane diameter, torus diameter, bordered pit aperture diameter, and ray tracheid abundance in comparison with trees adapted to severe summer drought conditions (Southern region and Balearic Islands region). The greater structural requirements of trees from the Inland Catalonia region, subjected to higher weight and wind loads, resulted in thick cell walls. Moreover, the large pits and more abundant ray tracheids in trees from this provenance would allow more efficient water transport and greater water storage capacity, respectively. The differences found between provenances suggest the adaptive nature of the anatomy of this species, which demonstrates the importance of the region of provenance when choosing reproduction material for reforestation. © Springer-Verlag 2009.

La innovación educativa va más allá del cambio metodológico y didáctico ya que implica una reflexión ideológica que nunca tiene lugar fuera de un contexto. Esta es la razón que explica la dificultad de aplicar el recurso o los materiales generados en los procesos innovadores de un contexto a otro sin el necesario debate. En este artículo nos proponemos realizar un estudio descriptivo que combine la explotación de la información contenida en los registros de innovación de la Base de Datos REDINED, tratados cuantitativa y cualitativamente. Para presentar el proceso técnico de la investigación hemos realizado una breve descripción del software utilizado: CDS/ISIS, que es un sistema de gestión documental desarrollado por la UNESCO que permite almacenar y recuperar grandes volúmenes de datos, así como la combinación de distintos tipos de búsquedas para las que hemos utilizado el programa WinISIS, que es una versión para Windows de CDS/ISIS en la que está disponible la base de datos REDINED. WinISIS permite realizar búsquedas a través del archivo invertido o búsquedas en texto libre basadas en la lectura secuencial del archivo Maestro, combinando los términos de búsqueda con operadores booleanos. Estas búsquedas nos facilitan obtener las estadísticas porcentuales de los éxitos de las peticiones formuladas a la base.

Mechanisms of drought resistance were studied in two xeric populations of Pinus canariensis and Pinus pinaster. Seedlings were grown in a hydroponic culture for four months. Gradual controlled drought was imposed during two weeks by adding Polyethylene glycol (PEG-6000) to the growing medium. Two levels of water deficit (Psi = -1MPa, Psi = -2 MPa) and a control treatment (Psi = -0.03 MPa) were tested. Relative water content (RWC) was markedly low at the end of the experimenBoth populations showed a high capacity for osmotic adjustment in needles as shown by the osmotic index, 0.63 (1.33 MPa at 80% RWC) for P. canariensis and 0.54 (1.25 MPa at 80% RWC) for P. pinaster. Root growth and root:shoot (stem + needles) ratio were increased by water deficiOpposite patterns of relative biomass allocation were assessed between stressed and control plants. While stressed seedlings assigned more dry matter to roots, non-stressed plants showed a higher relative needle weighThe growing media caused additional stress to the plants, thus comparisons with other drought protocols should be made carefully. Se estudiaron mecanismos de resistencia a la sequía en poblaciones áridas de P.canariensis y P. pinaster. Tras cuatro meses en cultivo hidropónico, se sometió a las plantas a un tratamiento de sequía durante dos semanas añadiendo polietilenglicol (PEG-6000) a la solución. Se evaluaron dos niveles de déficit hídrico (Psi = -1MPa, Psi = -2 MPa) y un tratamiento control (Psi = -0,03 MPa). El contenido hídrico relativo (RWC) de las plántulas fue muy bajo durante todo el ensayo. Las dos poblaciones mostraron una gran capacidad de ajuste osmótico con índices de ajuste osmótico de 0,63 (ajuste osmótico de 1,33 MPa a un 80% de RWC) en P. canariensis y 0,54 (ajuste osmótico de 1,25 MPa a un 80% de RWC) en P-. pinaster. El crecimiento radical y la relación raíz:parte aérea fueron estimulados por la sequía. Se encontraron patrones de reparto de biomasa opuestos entre las plantas estresadas y las control. Mientras que las primeras destinaron más materia seca a las raíces, las no estresadas invirtieron más en biomasa foliar. El medio de cultivo causó un estrés adicional a la planta por lo que las comparaciones de ensayos de sequía utilizando PEG con otros protocolos deben de tenerlo en cuenta.

Pine needles reflect some of the most outstanding xeromorphic characteristics of sclerophyllous plants. Detailed descriptive studies about their anatomy and morphology were carried out since the beginning of the past century but the role the different tissues play in adaptation to diverse environments is still little known. In this work we analyzed morphological and anatomical needle traits of seventeen natural populations of Pinus canariensis Chr. Sm. Ex DC to identify adaptive traits related to drought resistance and determine their variability throughout a wide range of ecological conditions. A Principal Component Analysis revealed two groups of traits, one related to drought adaptation maximizing gas exchange, avoiding water loss and storing water and the other to photosynthesis. Results support a predominantly mechanical function of hypodermis and a possible role of transfusion tissue to withstand dry conditions, thanks to its water storing capacity. The inversion of the patterns of the relative area of the dermal and transfusion tissues in the xeric region was justified due to the influence of the extreme dry Saharan wind from the East. A clear adaptation of Pinus canariensis needles to contrasted environments is evidenced suggesting distinct phenotypic needle features in the most xeric stands. © 2008 Springer-Verlag.

La progresiva implantación de portales educativos de distinta naturaleza requiere una definición y clasificación para su identificación, así como una enumeración de los elementos más comunes que se ofertan en ellos, para poder establecer un perfil de portal educativo. Para ello, en este trabajo se realiza una revisión de los principales portales educativos institucionales dependientes de las administraciones autonómicas para establecer el nivel de desarrollo que presentan y para conocer las posibles tendencias que se proyectan en su evolución. Además, también se advierte de la importancia de la implantación de algunos servicios de valor añadido para el apoyo y la mejora de las tareas educativas o didácticas, como son los blogs, wikis y webquests. ABSTRACT: The progressive running of different educational portals needs one defini-tion and classification for its identification, as well as, one enumeration of their usual elements to be able to set up one model of educational portal. This paper re-vises the main institutional of education portals of the Regional Governments to set up the level of development and to know their possible trends. Furthermore, it no-tices about the importance in the some added value services implementation for the support and the improvement of the educational tasks, as blogs, wikis and web-quests.

We tested genetic and environmental effects and their interaction on the behaviour of 21 provenances of Pinus canariensis Chr. Sm. Ex DC from the Canary Islands and three seed sources from Israel at seven study sites covering a wide range of ecological conditions. Survival and growth traits (height, diameter and polycyclism) and their relationship with environmental parameters were assessed to evaluate their adaptive value and establish patterns of variation of the species inside and outside its natural distribution area. The results showed a high level of ecotypic differentiation for survival. As a general pattern, seed sources from favourable environments exhibited lower survival rates at dry sites than those from harsh environments (r = –0.76, P

Internet y su tecnología han transformado los Medios de Comunicación Social, generando nuevos modelos comunicativos entre los que destacan los portales periodísticos como figuras emergentes. Para comprender este fenómeno es conve-niente realizar una revisión de la evolución del periodismo electrónico. Los portales periodísticos se están consolidando como nuevos medios de comunicación social y para disponer de una percepción adecuada del estado de la cuestión, es preciso un análisis taxonómico de los componentes de estos portales: productos informativos, productos documentales y servicios de valor añadido. Esta observación permitirá de-finir el grado de desarrollo en el que se encuentran los portales periodísticos, seña-lando tanto los aspectos más positivos como las carencias identificadas. Como resul-tado de la revisión se propone un modelo de referencia para el diseño de los portales periodísticos, con base en una serie de niveles que permitirán el establecimiento de un principio metodológico para futuros proyectos sobre esta cuestión. ABSTRACT: Internet has made the structures of the traditional mass media to stagger, having generated new communicative models among which the journalistic portals outstand as the most relevant examples. The present situation is the result of an evo-lutionary process, although the popularity of the Internet has recently caused a true outbreak. It is advisable, however, to carry out an exhaustive revision of the whole evolution of Digital Journalism up to today’s standards, with the journalistic portals turning into the new and independent mass media. A sensible perception of the this fact calls for a taxonomic analysis of the components of the portals: informative products, documentary products and added value services. This analysis will enable us to define the degree of development of these portals. The final result of this revi-sion should provide a model of reference for the designing and developing of Jour-nalistic Portals, based upon a series of development levels that will grant a method-ology background for future projects in this field.

La nueva forma de construir sitios web coloca al usu-rio en un lugar mucho más protagónico, de manera que puede participar de forma más activa. La Web se entiende ahora como la plataforma sobre la que se desa-rrollan las aplicaciones y a través de la cual los usuarios interaccionan con ella, porque las necesidades de los usuarios van más allá de la mera consulta de documentos publicados por otros autores, ahora sienten interés en editar ellos mismos sus documentos, bien de forma individual (un blog, por ejemplo) o de forma colectiva (una wiki, por ejemplo). Este nuevo paradigma se co-noce con el nombre de web 2.0 e incorpora una serie de ideas y servicios que le otorgan al usuario mayor capacidad de participación, las cuales pueden ser aprovechadas de forma muy interesante por las comunidades educativas, bien de forma personal o bien apoyándose en los recursos que disponen para ello las comunidades autónomas españolas en la Web, donde desarrollan y mantienen portales que comienzan a integrar productos y servicios 2.0, que ofrecen al usuario mayor participación y personalización de su espacio personal. El objetivo de este estudio es revisar la presencia y uso de estos productos y servicios en este tipo de portales. Los resultados obtenidos nos muestran que se ha iniciado el proceso de adaptación e implementación hacia los portales educativos 2.0 pero que aún queda mucho camino por recorrer. Asimismo, y como era previsible, se han detectado grandes diferencias entre unos portales y otros en cuanto a su grado de desarrollo.

Disregarded for centuries, Mediterranean pine forests in Spain have been severely affected by human activities including fires and livestock grazing. As a consequence, reforestation programs were started by the late 1800s, albeit the origin of the seeds was not considered until the late 1960s. In July 2005, a large Pinus pinaster Ait. forest, located in Guadalajara (central Spain), burned down. In this area, we studied fire-related fitness traits in natural stands (zone N) and compared them to those of trees sown with seeds from foreign sources (zone S). Cone production per hectare in zone N doubled that found in zone S. In addition, zone N resulted in more saplings per hectare as well as more small trees bearing cones than zone S. In zone S, trees showed thicker crowns and less fructification resulting in open formations with low intraspecific competition. Whereas in the natural stands the average percentage of serotiny per tree was 32%, in the sown stands only one serotinous cone was found in seven unburned harvested trees. Compared with zone S, the presence of seedlings after springtime was almost nine times higher in zone N in spite of the damaging effects of logging and removal of burnt wood.

14 páginas.- 6 figuras.- referencias.- Additional Supporting Information may be found online in the Supporting Information section at the end of the article https://nph.onlinelibrary.wiley.com/action/downloadSupplement?doi=10.1111%2Fnph.16746&file=nph16746-sup-0001-SupInfo.pdf, Hydraulic failure of the plant vascular system is a principal cause of forest die-off under drought. Accurate quantification of this process is essential to our understanding of the physiological mechanisms underpinning plant mortality. Imaging techniques increasingly are applied to estimate xylem cavitation resistance. These techniques allow forin situmeasurement of embolism formation in real time, although the benefits and trade-offs associated with different techniques have not been evaluated in detail. Here we compare two imaging methods, microcomputed tomography (microCT) and optical vulnerability (OV), to standard hydraulic methods for measurement of cavitation resistance in seven woody species representing a diversity of major phylogenetic and xylem anatomical groups. Across the seven species, there was strong agreement between cavitation resistance values (P-50) estimated from visualization techniques (microCT and OV) and between visual techniques and hydraulic techniques. The results indicate that visual techniques provide accurate estimates of cavitation resistance and the degree to which xylem hydraulic function is impacted by embolism. Results are discussed in the context of trade-offs associated with each technique and possible causes of discrepancy between estimates of cavitation resistance provided by visual and hydraulic techniques., This work was supported by an ARC Discovery Projec t(DP170100761) to BC and TJB and an ARC Future Fellowship (FT130101115) to BC. We thank Daniel Hausermann, ChrisHall and Anton Maksimenko from the Australian SynchrotronImaging and Medical Beamline in Melbourne for assisting withthe micro-computed tomography methodology, as well as thetechnical staff at SOLEIL. Travel funding for AG to attendbeamtime at SOLEIL was provided by the International Syn-chrotron Access Program (ISAP) managed by the Australian Syn-chrotron. CMR-D was supported by an Individual Fellowshipfrom the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agree-ment no. 751918-AgroPHYS

RESUMENEl uso de normas y estilos de descripción bibliográfica estándares a nivel internacional ha dotado a las revistas científicas de un considerable nivel de rigor y uniformidad para el intercambio y manejo de datos bibliográficos entre sistemas distintos, al influir positivamente en la difusión y el impacto de la producción científica. En pleno auge de la publicación en acceso abierto creemos conveniente estudiar estos patrones de comportamiento, concretamente en las revistas editadas en España. El análisis destaca la “herencia editorial” presente en las revistas de acceso abierto que procede de las revistas impresas en la forma de citación y las normas empleadas, en donde el estilo apa es el más utilizado en la muestra objeto de estudio. No obstante, el resultado global no es del todo satisfactorio debido al escaso porcentaje de uso de estas normas internacionales en las revistas españolas de acceso abierto.ABSTRACTThe use of international standards for bibliographic description and writing styles has imbued scientific journals with a considerable rigor and uniformity for the management and exchange of bibliographical data between diverse systems, enhancing dissemination and scientific production itself. At the current juncture of open access publishing, the study of these behavioral patterns exhibited in open access journals published in Spain seems particularly important. The analysis offered reveals the “print media legacy” evident in open access journals, embodied in apa standard citation conventions used in most journals examined in this study. Overall results, however, are not entirely satisfactory, because of the scarce use of such international standards in the Spanish open access journals.