Publications by authors named "G R Allan"

Background: This is an update of the original Cochrane review, published in 2017. Eight out of 10 major antihypertensive trials in adults, 65 years of age or older, attempted to achieve a target systolic blood pressure (BP) of < 160 mmHg. Collectively, these trials demonstrated cardiovascular benefit for treatment, compared to no treatment, for older adults with BP > 160 mmHg.

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Climate means and variability are shifting rapidly, leading to mismatches between climate and locally adapted plant traits. Phenotypic plasticity, the ability of a plant to respond to environmental conditions within a lifetime, may provide a buffer for plants to persist under increasing temperature and water stress. We used two reciprocal common gardens across a steep temperature gradient to investigate plasticity in six populations of Fremont cottonwood, an important foundation tree species in arid riparian ecosystems.

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Article Synopsis
  • Plants' survival and adaptation to environmental changes depend on their genetic traits and ability to adjust, but measuring these factors on a large scale is challenging.
  • Using a handheld spectrometer, researchers studied the leaf reflectance of the Populus fremontii species across different climates and gardens to detect genetic variations among populations.
  • The study found that genetic differences influenced leaf spectra significantly, with unique adjustments made by populations in response to environmental stresses, highlighting the importance of genetic identity for predicting plant responses to climate change.
  • Additionally, transferring plants to hotter environments diminished their photosynthetic efficiency, indicating a need for local adaptation to the specific climate.
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Increasing heatwaves are threatening forest ecosystems globally. Leaf thermal regulation and tolerance are important for plant survival during heatwaves, though the interaction between these processes and water availability is unclear. Genotypes of the widely distributed foundation tree species were studied in a controlled common garden during a record summer heatwave-where air temperature exceeded 48 °C.

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