Many studies have focused on the physiological and morphological responses of
Quercus suber to high temperatures and summer drought. Nevertheless, our understanding of the potential of this species ...to cope with climate change is incomplete. An increase in severity, length and frequency of summer droughts is expected in the Iberian Peninsula over the 21st century. We investigated the potential of cork oak to adapt to climate change in a 4-year study comparing seedling survival from thirteen Spanish populations in a common garden. Acorn size was evaluated as a possible adaptive trait enhancing stress resistance during establishment. Populations originating from sites with the driest summers exhibited the highest survival rates under dry conditions. These populations were characterized by bigger acorns, suggesting selection for this trait across sites experiencing drought. Our findings reveal that northern populations are not well adapted to cope with increasing drought but suggest that they might cope well with the moderate drought increase expected for these zones. However, continental populations are intermediately adapted to dry conditions, while drastic and fast increases in summer droughts are expected to occur in these regions. This extensive and quick change will provide scant chances to adapt making the populations of cork oak in these regions particularly vulnerable to the future climatic conditions.
Introduction
Active surveillance (AS) is considered a suitable management practice for those patients with low‐risk prostate cancer (PCa). At present, however, the role of multiparametric magnetic ...resonance imaging (mpMRI) in AS protocols has not yet been clearly established.
Outcomes
To determine the role of mpMRI and its ability to detect significant prostate cancer (SigPCa) in PCa patients enrolled in AS protocols.
Materials and Methods
There were 229 patients enrolled in an AS protocol between 2011 and 2020 at Reina Sofía University Hospital. MRI interpretation was based on PIRADS v.1 or v.2/2.1 classification. Demographics, clinical, and analytical data were collected and analyzed. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for mpMRI in different scenarios. We defined SigPCa and reclassification/progression as a Gleason score (GS) ≥ 3 + 4, a clinical stage ≥T2b, or an increase in PCa volume. Kaplan–Meier and log‐rank tests were used to estimate progression‐free survival time.
Results
Median age was 69.02 (±7.73) at diagnosis, with a 0.15 (±0.08) PSA density (PSAD). Eighty‐six patients were reclassified after confirmatory biopsy, with a suspicious mpMRI an indication for a clear reclassification and risk‐predictor factor in disease progression (p < 0.05). During follow‐up, 46 patients were changed from AS to active treatment mainly due to disease progression. Ninety patients underwent ≥2mpMRI during follow‐up, with a median follow‐up of 29 (15–49) months. Thirty‐four patients had a baseline suspicious mpMRI (at diagnostic or confirmatory biopsy): 14 patients with a PIRADS 3 and 20 patients with ≥PIRADS 4. From 14 patients with a PIRADS 3 baseline mpMRI, 29% progressed radiologically, with a 50% progression rate versus 10% (1/10 patients) for those with similar or decreased mpMRI risk. Of the 56 patients with a non‐suspicious baseline mpMRI (PIRADS < 2), 14 patients (25%) had an increased degree of radiological suspicion, with a detection rate of SigPCa of 29%. The mpMRI NPV during follow‐up was 0.91.
Conclusion
A suspicious mpMRI increases the reclassification and disease progression risk during follow‐up and plays an important role in monitoring biopsies. In addition, a high NPV at mpMRI follow‐up can help to decrease the need to monitor biopsies during AS.
Drought is the main selection agent in Mediterranean ecosystems and it has been suggested as an important evolutionary force responsible for population diversification in these types of environments. ...However, population divergence in quantitative traits can be driven by either natural selection, genetic drift or both. To investigate the roles of these forces on among-population divergence in ecophysiological traits related to drought tolerance (carbon isotope discrimination, specific leaf area, leaf size and leaf nitrogen content), we compared molecular and quantitative genetic differentiation in a common garden experiment including thirteen cork oak (Quercus suber L.) populations across a gradient of rainfall and temperature. Population differentiation for height, specific leaf area, leaf size and nitrogen leaf content measured during a dry year far exceeded the molecular differentiation measured by six nuclear microsatellites. Populations from dry-cool sites showed the lowest nitrogen leaf content and the smallest and thickest leaves contrasting with those from humid-warm sites. These results suggest (i) these traits are subjected to divergence selection and (ii) the genetic differences among populations are partly due to climate adaptation. By contrast, the low among-population divergence found in basal diameter, annual growth and carbon isotopic discrimination (a surrogate for water use efficiency) suggests low or no divergence selection for these traits. Among-population differentiation for neutral markers was not a good predictor for differentiation regarding the quantitative traits studied here, except for leaf size. The correlation observed between the genetic differentiation for leaf size and that for molecular markers was exclusively due to the association between leaf size and the microsatellite QpZAG46, which suggests a possible linkage between QpZAG46 and genes encoding for leaf size.
Ocular hypertension is a major risk factor for glaucoma, a neurodegenerative disease characterized by an irreversible decrease in ganglion cells and their axons. Macroglial and microglial cells ...appear to play an important role in the pathogenic mechanisms of the disease. Here, we study the effects of laser-induced ocular hypertension (OHT) in the macroglia, microglia and retinal ganglion cells (RGCs) of eyes with OHT (OHT-eyes) and contralateral eyes two weeks after lasering.
Two groups of adult Swiss mice were used: age-matched control (naïve, n=9); and lasered (n=9). In the lasered animals, both OHT-eyes and contralateral eyes were analyzed. Retinal whole-mounts were immunostained with antibodies against glial fibrillary acid protein (GFAP), neurofilament of 200 kD (NF-200), ionized calcium binding adaptor molecule (Iba-1) and major histocompatibility complex class II molecule (MHC-II). The GFAP-labeled retinal area (GFAP-RA), the intensity of GFAP immunoreaction (GFAP-IR), and the number of astrocytes and NF-200 + RGCs were quantified.
In comparison with naïve: i) astrocytes were more robust in contralateral eyes. In OHT-eyes, the astrocyte population was not homogeneous, given that astrocytes displaying only primary processes coexisted with astrocytes in which primary and secondary processes could be recognized, the former having less intense GFAP-IR (P<0.001); ii) GFAP-RA was increased in contralateral (P<.05) and decreased in OHT-eyes (P <0.001); iii) the mean intensity of GFAP-IR was higher in OHT-eyes (P<0.01), and the percentage of the retinal area occupied by GFAP+ cells with higher intensity levels was increased in contralateral (P=0.05) and in OHT-eyes (P<0.01); iv) both in contralateral and in OHT-eyes, GFAP was upregulated in Müller cells and microglia was activated; v) MHC-II was upregulated on macroglia and microglia. In microglia, it was similarly expressed in contralateral and OHT-eyes. By contrast, in macroglia, MHC-II upregulation was observed mainly in astrocytes in contralateral eyes and in Müller cells in OHT-eyes; vi) NF-200+ RGCs (degenerated cells) appeared in OHT-eyes with a trend for the GFAP-RA to decrease and for the NF-200+RGC number to increase from the center to the periphery (r= -0.45).
The use of the contralateral eye as an internal control in experimental induction of unilateral IOP should be reconsidered. The gliotic behavior in contralateral eyes could be related to the immune response. The absence of NF-200+RGCs (sign of RGC degeneration) leads us to postulate that the MHC-II upregulation in contralateral eyes could favor neuroprotection.
We make use of Friedrich's construction of the cylinder at spatial infinity to relate the logarithmic terms appearing in asymptotic expansions of components of the Weyl tensor to the freely ...specifiable parts of time symmetric initial data sets for the Einstein field equations. Our analysis is based on the assumption that a particular type of formal expansions near the cylinder at spatial infinity corresponds to the leading terms of actual solutions to the Einstein field equations. In particular, we show that if the Bach tensor of the initial conformal metric does not vanish at the point at infinity then the most singular component of the Weyl tensor decays near null infinity as O(r~−3lnr~) so that spacetime will not peel. We also provide necessary conditions on the initial data which should lead to a peeling spacetime. Finally, we show how to construct global spacetimes which are candidates for non-peeling (polyhomogeneous) asymptotics.
Heavy rain events are frequently recorded in the Western Mediterranean causing economic losses and even human casualties. The Western Mediterranean is a deep and almost closed sea surrounded by high ...mountain ranges and with little exchange of water with the Atlantic ocean. A main factor in the development of torrential rains is ocean-atmosphere exchanges of heat and moisture that can potentially destabilize air masses travelling over the sea. The study of air mass trajectories previous to the rain event permits the identification of sea areas that could probably contribute to the development or intensification of rainfall. From a previous Mediterranean sea surface temperature climatology, its spatio-temporal distribution patterns have been studied showing two main distribution modes in winter and summer and transitional regimes in spring and autumn. Hence, three heavy precipitation events, for such winter and summer sea temperature regimes and for fall transition, affecting the Valencia region have been selected to study the effect of sea surface temperature in torrential rains. Simulations with perturbed sea surface temperature in different areas along the air mass path were run to compare results with unperturbed simulation. The variation of sea surface temperature in certain areas caused significant changes in model accumulated values and its spatial distribution. Therefore, the existence of areas that at a greater extent favour air-sea interaction leading to the development of torrential rainfall in the Valencia region has been shown. This methodology could be extended to the whole Mediterranean basin to look for such potential recharge areas. The identification of sea areas that contribute to the development or intensification of heavy rain events in the Mediterranean countries could be a useful prognosis and/or monitoring tool.
We use an orthonormal frame approach to provide a general framework for the first order hyperbolic reduction of the Einstein equations coupled to a fairly generic class of matter models. Our analysis ...covers the special cases of dust and perfect fluid. We also provide a discussion of self-gravitating elastic matter. The frame is Fermi–Walker propagated and coordinates are chosen such as to satisfy the Lagrange condition. We show the propagation of the constraints of the Einstein-matter system.
Large-scale human-mediated translocation of plants is a widespread phenomenon throughout the world. In this study, we examine the extent to which exotic gene flow from conspecific plantations of ...mesic origin impacts pre- and post-dispersal fitness, seedling phenotype, and quantitative genetic variation of the relict southernmost native population of Scots pine (Pinus sylvestris var. nevadensis Christ). For this purpose, we conducted controlled pollinations to obtain native, exotic and intraspecific hybrid progenies for testing seed viability and seedling performance under experimental common-garden conditions mimicking the severe summer drought in the native population's environment. Proportion of aborted seeds was markedly higher in exotic (>60%) than in intraspecific hybrid (~24%) and native (18%) progenies. Seed germination time and rate were similar across genetic crosses. Hybrid and exotic seedlings died on average 1.2 and 0.8days earlier than local progenies when exposed to the drought treatment. Cumulative mortality rate was positively associated to biomass allocation in needles, suggesting that higher investment in needles is maladaptive in dry environments for P. sylvestris, probably because of increased total transpiration. Native progenies harbored higher genetic variation than exotic progenies, but similar to hybrids for most phenotypic traits, suggesting low impact of exotic gene flow on the levels of heritable genetic variation of the relict population. To the extent that our results held in natural conditions, they suggest that natural selection in the relict's dry natural environment could potentially hamper the effective establishment of exotic genes via seed and pollen dispersal from the plantations, and that exotic hybridization would not significantly affect the potential of early recruits in response to selection.
•F1 hybrid progenies are slightly less tolerant to drought than exotic and local seedlings.•Biomass allocation in needles negatively affects survival.•Exotic gene flow has low impact on the levels of heritable genetic variation.
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