Post-dispersal predation of Pinus pinaster Aiton seeds: key factors and effects on below-ground seed bank.

Seed bank dynamics constitute a pool of natural regeneration, a complex and key process for stand persistence. The present work analyses post-dispersal predation on a Pinus pinaster Ait. (Maritime Pine) below-ground seed bank. The study was carried out at the experimental site of Mata de Cuellar (Segovia-Central Spain), where an integrated analysis of Maritime Pine regeneration has been underway since 2004. Seed predation was monitored every month from 2010 to 2013. A generalized linear model was fitted using ‘next spring seed density’ as the response variable and seed rain, micro-site conditions and annual climate variability as explanatory variables. Seed rain, distance to the nearest stump, basal area and Walter’s drought index, along with percentage cover of herbaceous species, pine needle litter and shrub species had significant positive effects. The number of neighbouring trees had a significant negative effect on seed density. These results demonstrate how seed rain, summer drought and micro-site conditions are crucial to understanding the effects of predation on the below-ground seed bank. Though greater than null, the final seed bank might be insufficient for successful natural regeneration due to high mortality caused by difficult germination and establishment conditions.Instituto Universitario de Gestión Forestal Sostenibl

Diagramas de manejo de densidad para dos especies de pino mediterráneas en el este de España

Producción CientíficaStand Density Management Diagrams are useful tools for designing, displaying and evaluating alternative density management regimes in even-aged stands, with which to achieve a desired future stand condition. The stands studied, of Pinus halepensis and Pinus pinaster, have low productivity, and managers need easy, efficient tools to obtain the best yield. These diagrams help the managers of these stands determine thinning prescriptions. The relationship between stand density, dominant height, quadratic mean diameter and stand volume is represented in just one graph. Two equations were fitted simultaneously: one that relates quadratic mean diameter with stand density and dominant height, and another that relates total stand volume with quadratic mean diameter, stand density and dominant height.Los Diagramas de Manejo de Densidad de Masa son útiles herramientas para el diseño, desarrollo y evaluación de regímenes de densidad alternativos en masas regulares, para alcanzar unas condiciones de masa deseadas. Las masas estudiadas, de Pinus halepensis y Pinus pinaster tienen una baja productividad, y los gestores necesitan herramientas fáciles de usar y eficientes para obtener la mayor rentabilidad. Estos diagramas ayudan a los gestores de estas masas en la toma de decisiones selvícolas. La relación entre la densidad de masa, la altura dominante, el diámetro medio cuadrático y el volumen total se la masa se representa en sólo un gráfico. Se ajustaron dos ecuaciones simultáneamente: una que relaciona el diámetro medio cuadrático con la densidad de la masa y la altura dominante, y otra que relaciona el volumen total de la masa con el diámetro medio cuadrático, densidad de la masa y altura dominante.Ministerio de Educación y Ciencia (Project AGL2007-65795-C02-01)Ministerio de Educación y Ciencia (Project AGL2007-65795-C01-01

Long-term implications of traditional forest regulation methods applied to Maritime pine (Pinus pinaster Ait.) forests in central Spain: a century of management plans

Producción CientíficaPinus pinaster stands in the northern Iberian range (Spain) have been under forest management plans for more than a century. The main goals have been sustainable yield and conservation and enhancement of forest conditions. In the study area, forest management plan implementation started to be effective in the late 19th and early 20th centuries and the plans have been evaluated every ten years. In these forests, a permanent forest compartment method has been applied as the management system. Different regeneration methods have been applied (uniform shelterwood and clear cutting in Soria, selective and uniform shelterwood and continuous cover forestry in Teruel). To analyse the evolution of each forest group, five management indicators have been tested in this study: number of merchantable trees, standing volume, resin production, allowable yield, and harvested volume. Forest situation improvement and maintenance of forest integrity are not only a consequence of the actions planed by foresters, they are also influenced by socio-economic transformations that have occurred during the last century such as the weakness of the resin market, decreasing demand for fire wood, restriction of pasture activities, and increasing recreation use.Ministerio de Educación y Ciencia (project AGL-2001-1780)Ministerio de Educación y Ciencia (project AGL2004-07094-C02-02)Ministerio de Educación y Ciencia (project AGL2007-65795-C02-01

Determination of Methane Oxidation in Landfill Fugitive Emissions by 13C Isotope Measurements

Still today, the final destiny of a large part of the waste dumped is landfilling, which is an important source of methane. Quantifying the amount of methane that is oxidized when the landfill gas passes through the seal, it can provide valuable information when determining the total GHG potential emission of a landfill. In this work, methane oxidation has been determined for landfill gas samples taken on the surface of three Spanish landfills. For this, it has been determined the 13C isotopic signal in methane by cavity ring-down spectroscopy (CRDS-WS). Previously, the preference of methanotrophic bacteria for 12C isotope versus 13C has been quantified using soil samples from the three landfills. The results obtained show a great variability, ranging from 0 to 70% of methane oxidized. This variability can be explained with the specific characteristics of each sample, suggesting a consistent methodology

Biomechanical Test of a New Endoprosthesis for Cylindrical Medullary Canals in Dogs

Exo-endoprosthesis is a limb salvage procedure for animals, although only expensive metal devices have been described. Now-a-days, new materials for this type of implant could be considered due to novel and affordable manufacturing techniques. However, a factor of safety (FoS) should be considered. There are kinetic and kinematic studies of canine natural gaits, which can be used to establish an FoS for mechanical tests for new non-metallic devices. Polyetheretherketone (PEEK) is used in different specialties in human medicine. Its mechanical properties (and its close mechanical stiffness to that of bone) make this polymer an alternative to metals in veterinary traumatology. PEEK could also be used in 3D printing. The suitability of a novel inner part of an exo-endoprosthesis manufactured by fuse deposition modeling (FDM) was presented in this study for long canine bones. Mechanical characterization of 3D-printed PEEK material and ex vivo mechanical tests of a customized endoprosthesis were performed to address it. Young's modulus of 3D-printed PEEK suffered a reduction of 30% in relation to bulk PEEK. Customized 3D-printed PEEK endoprostheses had promising outcomes for the tibiae of 20 kg dogs. Pure compression tests of the non-inserted endoprostheses showed a maximum force of 936 +/- 199 N. In the bending tests of non-inserted endoprostheses, the PEEK part remained intact. Quasistatic mechanical tests of bone-inserted endoprostheses (compression-bending and pure compression tests) reached a maximum force of 785 +/- 101 N and 1,642 +/- 447 N, respectively. In fatigue tests, the samples reached 500,000 cycles without failure or detriment to their quasistatic results. These outcomes surpass the natural weight-bearing of dogs, even during a galloping pace. In conclusion, the 3D-printed PEEK part of the endoprosthesis for an exo-endoprosthesis can withstand loading, even during a galloping pace.Depto. de Medicina y Cirugía AnimalFac. de VeterinariaTRUEComunidad de Madridpu

Can seed production and restricted dispersal limit recruitment in Pinus pinaster Aiton from the Spanish Northern Plateau?

Natural regeneration faces increasing difficulties in dry forests from the Mediterranean basin, including for normally well-regenerating species such as maritime pine (Pinus pinaster Aiton). In this paper, we studied female fertility, seed dispersal and spread rates in P. pinaster from the Spanish Northern Plateau, where natural regeneration failure is a main concern for forest managers. For this purpose we periodically collected data from seed traps and trees located at two core locations across several years. We found significant variation in interannual cone production, with the best seed trees being the same across years. In addition, we found highly skewed distributions of female reproductive effort and large fertility differences across stands located few kilometres away. Annual seed dispersal kernels fitted lognormal or 2Dt models depending on the stand analysed, with median dispersal distances between 14 and 25 m. Kernels fitted for maximum dispersal periods showed an outstanding intraseasonal variation of median dispersal distances, from 10 to 54 m, in association to variable patterns of rainfall and maximum wind speed. The amount of seed produced appeared to be enough to guarantee the natural regeneration of the stands during the typical 20-year regeneration period. Colonisation simulations concluded that Mediterranean maritime pine has a notable dispersion capacity, which is strongly influenced by levels of fecundity and, especially, by the number and frequency of long-distance dispersal events. The latter play a key role in tree dispersion processes through enlarging the occupied area and fostering the invasion of abandoned crop land

Determination of methane and carbon dioxide surface emissions in a Spanish landfill

Fugitive emissions from the surface of landfills constitute an important source of carbon dioxide and methane that are emitted to the atmosphere and contribute to the greenhouse effects. Quantifying those emissions can give valuable information, not only, on the amount of those gases which are released into the atmosphere but on their environmental consequences. They can also help to evaluate another aspects related to the landfill management like the seal efficiency or the gas recovery. Quantifying these emissions is not an easy task, due to the heterogeneity of the waste into the landfills, their huge dimensions and the influence of others factors like the site meteorology. Several measurement methods as well as prediction models for determine this type of emissions can be found in the bibliography. In this study a process in two steps, as described on the Guidance on monitoring landfill gas surface emissions (EA 2010), was followed in order to obtain the fugitive emissions of two landfill sites in Madrid (Spain). The first step consists on a walkover survey. At this stage the gas concentration close to the surface is monitored and zones with equal concentrations are defined. At the same time, significant emission sources and failures in the gas collection system are identified. All this information is used to choose the sample points for the second step, the flux box study. A flux box or flux chamber is a well known volume dispositive that allows to accumulate and to quantify over time emissions emanating from a given area of the landfill. To measure the composition of methane inside the flux box, a portable detector based on Infrared (IR) Absorption Spectroscopy (Sensit PMD) in combination with an electronic narrow band pass filter technology is being used. Carbon dioxide emissions were obtained using a passive IR sensor for CO2 (Kimo HQ210). Some preliminary results show the possibility of quantifying emissions rates from less than 1 mg/m2h to 104 mg/m2h or even higher. From a number of measures of this type in the selected emissions points the total amount of the surface emission of the landfill could be estimated. This method has been used in two landfills. The first one is a closed landfill that has been exploited for almost 40 years and was closed in 2000. In this case the landfill gas extracted is being used to generate electricity. The other one corresponds to a landfill which is still in use and the extracted gas is being burnt in a flare. Another critical difference between the two landfills is the type of cover used. In the closed landfill there is a high density polyethylene film while in the other one there is only a clay and sand barrier as cover. The walkover survey results show lower concentrations of methane on the closed landfill. This is an evidence of the effectiveness of a good seal combined with the active extraction and use of the gas to reduce methane release

Identification of non-coding genetic variants in samples from hypoxemic respiratory disease patients that affect the transcriptional response to hypoxia

A wide range of diseases course with an unbalance between the consumption of oxygen by tissues and its supply. This situation triggers a transcriptional response, mediated by the hypoxia inducible factors (HIFs), that aims to restore oxygen homeostasis. Little is known about the inter-individual variation in this response and its role in the progression of disease. Herein, we sought to identify common genetic variants mapping to hypoxia response elements (HREs) and characterize their effect on transcription. To this end, we constructed a list of genome-wide HIF-binding regions from publicly available experimental datasets and studied the genetic variability in these regions by targeted re-sequencing of genomic samples from 96 chronic obstructive pulmonary disease and 144 obstructive sleep apnea patients. This study identified 14 frequent variants disrupting potential HREs. The analysis of the genomic regions containing these variants by means of reporter assays revealed that variants rs1009329, rs6593210 and rs150921338 impaired the transcriptional response to hypoxia. Finally, using genome editing we confirmed the functional role of rs6593210 in the transcriptional regulation of EGFR. In summary, we found that inter-individual variability in non-coding regions affect the response to hypoxia and could potentially impact on the progression of pulmonary diseases.Ministerio de Ciencia e Innovación (Spanish Ministry of Science and Innovation, MICINN) [SAF2011 24225 to LdelP, SAF2014-53819-R to L.delP., B.J.]; Comunidad Autónoma de Madrid [S2010/BMD-2542 to L.delP., F.G.R., J.A.], Sociedad Española de Neumología y Cirugía Torácica (SEPAR) [34/2013 to LdelP, F.G.R.]; Fondo de Investigación Sanitaria/Instituto de Salud Carlos III [PI13-01512 to F.G.R.]; Fundación Caja Madrid (Beca de Movilidad para Profesores de las Universidades Públicas de Madrid 2011–2012 to L.delP); Canadian Institutes of Health Research (CIHR) [MOP-82875 to W.W.W.]; Natural Sciences and Engineering Research Council of Canada (NSERC) [RGPIN355532-10 to W.W.W.]; National Institutes of Health [1R01GM084875 toW.W.W.]; CSIC (Spanish National Research Council) [JAE-Doc grant-2010 to O.R., in part by the European Social Fund]. Spanish science, technology and innovation contract [University of Castilla-LaMancha-2014 to O.R., in part by the European Social Fund]. Funding for open access charge: MICINN [SAF2011 24225 to L.delP., SAF2014-53819-R to L.delP., B.J.

Markers of endothelial damage in patients with chronic kidney disease on hemodialysis

Patients with Stage 5 chronic kidney disease who are on hemodialysis (HD) remain in a chronic inflammatory state, characterized by the accumulation of uremic toxins that induce endothelial damage and cardiovascular disease (CVD). Our aim was to examine microvesicles (MVs), monocyte subpopulations, and angiopoietins (Ang) to identify prognostic markers in HD patients with or without diabetes mellitus (DM). A total of 160 prevalent HD patients from 10 centers across Spain were obtained from the Biobank of the Nephrology Renal Network (Madrid, Spain): 80 patients with DM and 80 patients without DM who were matched for clinical and demographic criteria. MVs from plasma and several monocyte subpopulations (CD142+/CD16+, CD14+/CD162+) were analyzed by flow cytometry, and the plasma concentrations of Ang1 and Ang2 were quantified by ELISA. Data on CVD were gathered over the 5.5 yr after these samples were obtained. MV level, monocyte subpopulations (CD14+/CD162+ and CD142+/CD16+), and Ang2-to-Ang1 ratios increased in HD patients with DM compared with non-DM patients. Moreover, MV level above the median (264 MVs/µl) was associated independently with greater mortality. MVs, monocyte subpopulations, and Ang2-to-Ang1 ratio can be used as predictors for CVD. In addition, MV level has a potential predictive value in the prevention of CVD in HD patients. These parameters undergo more extensive changes in patients with DM.Support for this work was provided by Plan Nacional de IDi Proyectos de Investigación en Salud of Instituto de Salud Carlos III (ISCIII)–Subdirección General de Evaluación, Fondos de desarrollo regional (FEDER; PI11/01536, PI12/01489, PI14/00806, PI15/01785); Junta de Andalucía grants (P010-CTS-6337, P11-CTS-7352); and Fundación Nefrológica. P. Buendía, A. Carmona, and C. Luna-Ruiz are fellows from Consejería de Innovacion, Ciencia y Empresa, Junta de Andalucía