Photosynthetic thermal tolerance and recovery to short duration temperature stress in desert and montane plants: A comparative study

Climate change models predict an increase in frequency and amplitude of extreme weather events, including heat waves. To better predict how the composition and distribution of plant assemblages might respond to these changes in temperature, it is important to understand how species currently respond to these extremes. Photosynthetic thermal tolerance (T25)and photosynthetic recovery (RT25) were quantified in 27 species. We also studied the relationships between T25, RT25 and leaf mass per area (LMA). Leaf temperature was also monitored in the field. Leaves used in this study were collected from two distinct environments representing desert and montane plant assemblages. T25 and RT25 were measured using a chlorophyll fluorescence protocol incorporating sub-saturating light and short duration heat stress. Mean T25and LMA were significantly different between environments. Mean RT25 was not significantly different between environments. There was a positive relationship between T25 and LMA in both environments. The ability to recover from heat stress does not differ between two biomes that experience vastly different mean maximum temperatures during the summer months. LMA is a predictive leaf trait for thermal tolerance

Potential use of oxygen as a metabolic biosensor in combination with T2*-weighted MRI to define the ischemic penumbra

We describe a novel magnetic resonance imaging technique for detecting metabolism indirectly through changes in oxyhemoglobin:deoxyhemoglobin ratios and T2* signal change during ‘oxygen challenge’ (OC, 5 mins 100% O2). During OC, T2* increase reflects O2 binding to deoxyhemoglobin, which is formed when metabolizing tissues take up oxygen. Here OC has been applied to identify tissue metabolism within the ischemic brain. Permanent middle cerebral artery occlusion was induced in rats. In series 1 scanning (n=5), diffusion-weighted imaging (DWI) was performed, followed by echo-planar T2* acquired during OC and perfusion-weighted imaging (PWI, arterial spin labeling). Oxygen challenge induced a T2* signal increase of 1.8%, 3.7%, and 0.24% in the contralateral cortex, ipsilateral cortex within the PWI/DWI mismatch zone, and ischemic core, respectively. T2* and apparent diffusion coefficient (ADC) map coregistration revealed that the T2* signal increase extended into the ADC lesion (3.4%). In series 2 (n=5), FLASH T2* and ADC maps coregistered with histology revealed a T2* signal increase of 4.9% in the histologically defined border zone (55% normal neuronal morphology, located within the ADC lesion boundary) compared with a 0.7% increase in the cortical ischemic core (92% neuronal ischemic cell change, core ADC lesion). Oxygen challenge has potential clinical utility and, by distinguishing metabolically active and inactive tissues within hypoperfused regions, could provide a more precise assessment of penumbra

On-orbit performance of the Spitzer Space Telescope

The Spitzer Space Telescope (formally known as SIRTF) was successfully launched on August 25, 2003, and has completed its initial in-orbit checkout and science validation and calibration period. The measured performance of the observatory has met or exceeded all of its high-level requirements, it entered normal operations in January 2004, and is returning high-quality science data. A superfluid-helium cooled 85 cm diameter telescope provides extremely low infrared backgrounds and feeds three science instruments covering wavelengths ranging from 3.6 to 160 microns. The telescope optical quality is excellent, providing diffraction-limited performance down to wavelengths below 6.5 microns. Based on the first helium mass and boil-off rate measurements, a cryogenic lifetime in excess of 5 years is expected. This presentation will provide a summary of the overall performance of the observatory, with an emphasis on those performance parameters that have the greatest impact on its ultimate science return

Body Composition Measurements from Birth through 5 Years: Challenges, Gaps, and Existing & Emerging Technologies—A National Institutes of Health workshop

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156150/2/obr13033_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156150/1/obr13033.pd

Comparison of Fencing Designs for Excluding Deer from Roadways

We evaluated the efficacy of several fencing designs for restricting movements of 18 captive, female white-tailed deer (Odocoelus virginianus), including standard wovenwire fencing (1.2-m, 1.5-m, 1.8-m, 2.1-m, and 2.4-m tall), opaque fencing (1.2-m, 1.5-m, and 1.8-m tall), and an outrigger fence (i.e., 0.6-m outriggers attached to a 1.2-m-tall wire fence angled at 45º). We recorded the number of successful fence crossings for each deer and characterized behaviors associated with each failed crossing attempt. No deer crossed the 2.4-m fence, whereas all deer crossed the 1.2-m fence. We observed no differences in crossing success between woven-wire and opaque fencing at height

An Electronic Adherence Measurement Intervention to Reduce Clinical Inertia in the Treatment of Uncontrolled Hypertension: The MATCH Cluster Randomized Clinical Trial

BACKGROUND: To appropriately manage uncontrolled hypertension, clinicians must decide whether blood pressure (BP) is above goal due to a need for additional medication or to medication nonadherence. Yet, clinicians are poor judges of adherence, and uncertainty about adherence may promote inertia with respect to medication modification. OBJECTIVE: We aimed to determine the effect of sharing electronically-measured adherence data with clinicians on the management of uncontrolled hypertension. DESIGN: This was a cluster randomized trial. PARTICIPANTS: Twenty-four primary care providers (12 intervention, 12 usual care; cluster units) and 100 patients with uncontrolled hypertension (65 intervention, 35 usual care) were included in the study. INTERVENTIONS: At one visit per patient, clinicians in the intervention group received a report summarizing electronically measured adherence to the BP regimen and recommended clinical actions. Clinicians in the control group did not receive a report. MAIN MEASURES: The primary outcome was the proportion of visits with appropriate clinical management (i.e., treatment intensification among adherent patients and adherence counseling among nonadherent patients). Secondary outcomes included patient-rated quality of care and communication during the visit. KEY RESULTS: The proportion of visits with appropriate clinical management was higher in the intervention group than the control group (45 out of 65; 69 %) versus (12 out of 35; 34 %; p = 0.001). A higher proportion of adherent patients in the intervention group had their regimen intensified (p = 0.01), and a higher proportion of nonadherent patients in the intervention group received adherence counseling (p = 0.005). Patients in the intervention group were more likely to give their clinician high ratings on quality of care (p = 0.05), and on measures of patient-centered (p = 0.001) and collaborative communication (p = 0.02). CONCLUSIONS: Providing clinicians with electronically-measured antihypertensive adherence reports reduces inertia in the management of uncontrolled hypertension. TRIAL REGISTRATION: NCT01257347 ; http://clinicaltrials.gov/show/ NCT01257347

On-orbit performance of the Spitzer Space Telescope

The Spitzer Space Telescope (formally known as SIRTF) was successfully launched on August 25, 2003, and has completed its initial in-orbit checkout and science validation and calibration period. The measured performance of the observatory has met or exceeded all of its high-level requirements, it entered normal operations in January 2004, and is returning high-quality science data. A superfluid-helium cooled 85 cm diameter telescope provides extremely low infrared backgrounds and feeds three science instruments covering wavelengths ranging from 3.6 to 160 microns. The telescope optical quality is excellent, providing diffraction-limited performance down to wavelengths below 6.5 microns. Based on the first helium mass and boil-off rate measurements, a cryogenic lifetime in excess of 5 years is expected. This presentation will provide a summary of the overall performance of the observatory, with an emphasis on those performance parameters that have the greatest impact on its ultimate science return