2,028 research outputs found

    Modelling Pinus pinea forest management to attain natural regeneration under present and future climatic scenarios

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    Natural regeneration-based silviculture has been increasingly regarded as a reliable option in sustainable forest management. However, successful natural regeneration is not always easy to achieve. Recently, new concerns have arisen because of changing future climate. To date, regeneration models have proved helpful in decision-making concerning natural regeneration. The implementation of such models into optimization routines is a promising approach in providing forest managers with accurate tools for forest planning. In the present study, we present a stochastic multistage regeneration model for Pinus pinea L. managed woodlands in Central Spain, where regeneration has been historically unsuccessful. The model is able to quantify recruitment under different silviculture alternatives and varying climatic scenarios, with further application to optimize management scheduling. The regeneration process in the species showed high between-year variation, with all subprocesses (seed production, dispersal, germination, predation, and seedling survival) having the potential to become bottlenecks. However, model simulations demonstrate that current intensive management is responsible for regeneration failure in the long term. Specifically, stand densities at rotation age are too low to guarantee adequate dispersal, the optimal density of seed-producing trees being around 150 stems·ha−1. In addition, rotation length needs to be extended up to 120 years to benefit from the higher seed production of older trees. Stochastic optimization confirms these results. Regeneration does not appear to worsen under climate change conditions; the species exhibiting resilience worthy of broader consideration in Mediterranean silviculture

    Micromammalian faunas from the middle miocene (middle Aragonian) of the Tudela formation (Ebro Basin, Spain)

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    Two new fossil micromammal localities of Middle Miocene age (Pico del Fraile 2, PF2 and Sancho Abarca 5, SA5) from the Tudela Formation (northeastern Ebro Basin) are described. PF2 contains rodents and insectivores of Aragonian age (local zone Dc). The rodent assemblage from the locality SA5 is very scarce and probably of Middle Aragonian age, like PF2. The micromammal fauna from the locality PF2 is very similar to that from Valdemoros 3B (VA3B) (Calatayud-Daroca Basin), including Microdyromys cf. remmerti, a species until now only described from the Miocene of the Daroca-Villafeliche area. Among the fauna recorded in PF2, a form of Democricetodon is described. The sedimentary record of the Pico del Fraile and Sancho Abarca sections and the mammalian findings extend the stratigraphic and paleontological knowledge of this part of the Ebro Basin, and allow its study in a continuous stratigraphic context

    IgG4-related disease: results from a multicenter Spanish registry

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    IgG4-related disease (IgG4-RD) is a rare entity consisting of inflammation and fibrosis that has been described in multiple organs. Concrete diagnostic criteria have been established recently and there is a lack of large series of patients.To describe the clinical presentation, histopathological characteristics, treatment and evolution of a series of IgG4-RD Spanish patients.A retrospective multicenter study was performed. Twelve hospitals across Spain included patients meeting the current 2012 consensus criteria on IgG4-RD diagnosis.Fifty-five patients were included in the study, 38 of whom (69.1%) were male. Median age at diagnosis was 53 years. Thirty (54.5%) patients were included in the Histologically Highly Suggestive IgG4-RD group and 25 (45.5%) in the probable IgG4-RD group. Twenty-six (47.3%) patients had more than 1 organ affected at presentation. The most frequently affected organs were: retroperitoneum, orbital pseudotumor, pancreas, salivary and lachrymal glands, and maxillary sinuses.Corticosteroids were the mainstay of treatment (46 patients, 83.6%). Eighteen patients (32.7%) required additional immunosuppressive agents. Twenty-four (43.6%) patients achieved a complete response and 26 (43.7%) presented a partial response (<50% of regression) after 22 months of follow-up. No deaths were attributed directly to IgG4-RD and malignancy was infrequent.This is the largest IgG4-RD series reported in Europe. Patients were middle-aged males, with histologically probable IgG4-RD. The systemic form of the disease was frequent, involving mainly sites of the head and abdomen. Corticosteroids were an effective first line treatment, sometimes combined with immunosuppressive agents. Neither fatalities nor malignancies were attributed to IgG4-RD

    Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

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    The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum
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