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1.
Buma  B.  Harvey  B. J.  Gavin  D. G.  Kelly  R.  Loboda  T.  McNeil  B. E.  Marlon  J. R.  Meddens  A. J. H.  Morris  J. L.  Raffa  K. F.  Shuman  B.  Smithwick  E. A. H.  McLauchlan  K. K. 《Landscape Ecology》2019,34(1):17-33
Context

Predicting ecosystem resilience is a challenge, especially as climate change alters disturbance regimes and conditions for recovery. Recent research has highlighted the importance of spatially-explicit disturbance and resilience processes to long-term ecosystem dynamics. “Neoecological” approaches characterize resilience mechanisms at relatively fine spatio-temporal resolutions, but results are difficult to extrapolate across broad temporal scales or climatic ranges. Paleoecological methodologies can consider the effects of climates that differ from today. However, they are often limited to coarse-grained spatio-temporal resolutions.

Methods

In this synthesis, we describe implicit and explicit examples of studies that incorporate both neo- and paleoecological approaches. We propose ways to build on the strengths of both approaches in an explicit and proactive fashion.

Results

Linking the two approaches is a powerful way to surpass their respective limitations. Aligning spatial scales is critical: Paleoecological sampling design should incorporate knowledge of the spatial characteristics of the disturbance process, and neoecological studies benefit from a longer-term context to their conclusions. In some cases, modeling can incorporate non-spatial data from paleoecological records or emerging spatial paleo-data networks with mechanistic disturbance/recovery processes that operate at fine spatiotemporal scales.

Conclusions

Linking these two complementary approaches is a powerful way to build a complete understanding of ecosystem disturbance and resilience.

  相似文献   
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Developing more stress‐tolerant crops will require greater knowledge of the physiological basis of stress tolerance. Here, we explore how biomass declines in response to salinity relate to leaf traits across 20 genotypes of cultivated sunflower (Helianthus annuus). Plant growth, leaf physiological traits and leaf elemental composition were assessed after 21 days of salinity treatments (0, 50, 100, 150 or 200 mM NaCl) in a greenhouse study. There was a trade‐off in performance such that vigorous genotypes, those with higher biomass at 0 mM NaCl, had both a larger absolute decrease and proportional decrease in biomass due to increased salinity. More vigorous genotypes at control were less tolerant to salinity. Contrary to expectation, genotypes with a low increase in leaf Na and decrease in K:Na were not better at maintaining biomass with increasing salinity. Rather, genotypes with a greater reduction in leaf S and K content were better at maintaining biomass at increased salinity. While we found an overall trade‐off between sunflower vigour and salt tolerance, some genotypes were more tolerant than expected. Further analysis of the traits and mechanisms underlying this trade‐off may allow us to breed these into high‐vigour genotypes in order to increase their salt tolerance.  相似文献   
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Patchy meningeal and parenchymal contrast enhancement of the spinal cord with multifocal central canal dilations was noted in a computed tomography myelogram of the cervical spine of a 6-month-old intact female coonhound with a confirmed diagnosis of canine juvenile polyarteritis and associated hemorrhage within the central canal.  相似文献   
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Canine osteosarcoma is an aggressive cancer, comprising 85% of canine bone neoplasms. Current treatment practices of surgery and chemotherapy increase 1-year survival by only 45%. The curcumin analogue RL71, has demonstrated potent in vitro and in vivo efficacy in several models of human breast cancer through increased apoptosis and cell cycle arrest. Thus, the present study aimed to investigate efficacy of curcumin analogues in two canine osteosarcoma cell lines. Osteosarcoma cell viability was assessed using the sulforhodamine B assay and mechanisms of action were determined by analysing the levels of cell cycle and apoptotic regulatory proteins via Western blotting. Further evidence was obtained using flow cytometry to detect cell cycle distribution and the number of apoptotic cells. RL71 was the most potent curcumin analogue with EC50 values of 0.64 ± 0.04 and 0.38 ± 0.009 μM (n = 3) in D-17 (commercial) and Gracie canine osteosarcoma cells, respectively. RL71 significantly increased the ratio of cleaved-caspase 3 to pro-caspase 3 and the level of apoptotic cells at the 2× and 5× EC50 concentration (p < 0.001, n = 3). Furthermore, at the same concentration, RL71 significantly increased the number of cells in the G2/M phase. In conclusion, RL71 has potent cytotoxic activity in canine osteosarcoma cells triggering G2/M arrest and apoptosis at concentrations achievable in vivo. Future research should further investigate molecular mechanisms for these changes in other canine osteosarcoma cell lines prior to in vivo investigation.  相似文献   
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Avena sativa L. subsp. nudisativa has the ability to produce naked grains. Genetic studies on the naked trait of oat began over a century ago, but the genetic and molecular factors associated with the expression of this trait have not been fully clarified. The objectives of this study were to evaluate the naked trait in two oat populations of recombinant inbred lines (RILs), to determine the number of genes, to estimate the heritability, and to map genomic regions associated with the naked trait in hexaploid oat. Parental lines and RILs of each population were screened for the naked trait from plants grown in the field over a 2 year period. Based on the phenotypic data, the oat RILs were classed as naked, partially naked, partially hulled and hulled. In both populations and years, a great number of RILs showed variable expressivity for the naked trait. The genetic analysis indicated the action of a major gene (N1) with the action of modifying genes controlling the formation of naked grains. The results of the estimate of heritability show that environmental conditions do not have a great influence in determining the naked trait. The quantitative trait loci analysis detected a genomic region with a large effect on the naked trait that explained more than 50% of the phenotypic variation. Further studies are needed to validate the use of these molecular markers to assist breeding programs to select high quality and stable naked oat cultivars.  相似文献   
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