Near-surface remote sensing of spatial and temporal variation in canopy phenology

There is a need to document how plant phenology is responding to global change factors, particularly warming trends. “Near-surface” remote sensing, using radiometric instruments or imaging sensors, has great potential to improve phenological monitoring because automated observations can be made at high temporal frequency. Here we build on previous work and show how inexpensive, networked digital cameras (“webcams”) can be used to document spatial and temporal variation in the spring and autumn phenology of forest canopies. We use two years of imagery from a deciduous, northern hardwood site, and one year of imagery from a coniferous, boreal transition site. A quantitative signal is obtained by splitting images into separate red, green, and blue color channels and calculating the relative brightness of each channel for “regions of interest” within each image. We put the observed phenological signal in context by relating it to seasonal patterns of gross primary productivity, inferred from eddy covariance measurements of surface–atmosphere CO2 exchange. We show that spring increases, and autumn decreases, in canopy greenness can be detected in both deciduous and coniferous stands. In deciduous stands, an autumn red peak is also observed. The timing and rate of spring development and autumn senescence varies across the canopy, with greater variability in autumn than spring. Interannual variation in phenology can be detected both visually and quantitatively; delayed spring onset in 2007 compared to 2006 is related to a prolonged cold spell from day 85 to day 110. This work lays the foundation for regional- to continental-scale camera-based monitoring of phenology at network observatory sites, e.g., National Ecological Observatory Network (NEON) or AmeriFlux

An Evaluation of the Load-Displacement Behavior and Load Test Interpretation of Micropiles in Rock

This paper summarizes a series of never-before reported axial compression load tests conducted on single micropiles that are embedded in or constructed on rock. These data are augmented by load tests on similar micropiles that have been reported by others. The observed displacements at the maximum test load (QMAX) and reported unfactored design load (QDL) are summarized. In addition, the small-strain load-displacement behavior of these foundations is evaluated by comparing the initial tangent slope (IS) to the theoretical elastic slope (ES), which is calculated by modeling the micropile as a free-standing column exhibiting fully -composite behavior. The data demonstrate that the ES/IS ratio has a strong dependence on the slenderness ratio D[depth]/B[diameter]. The observed results for micropiles in rock are discussed in the context of the micropile load test acceptance criteria proposed by the Deep Foundations Institute (DFI, 2001). In addition, recommendations are proposed for the maximum acceptable vertical displacement under the unfactored design load for such micropiles

Antibody-based detection of protein phosphorylation status to track the efficacy of novel therapies using nanogram protein quantities from stem cells and cell lines

This protocol describes a highly reproducible antibody-based method that provides protein level and phosphorylation status information from nanogram quantities of protein cell lysate. Nanocapillary isoelectric focusing (cIEF) combines with UV-activated linking chemistry to detect changes in phosphorylation status. As an example application, we describe how to detect changes in response to tyrosine kinase inhibitors (TKIs) in the phosphorylation status of the adaptor protein ​CrkL, a major substrate of the oncogenic tyrosine kinase ​BCR-​ABL in chronic myeloid leukemia (CML), using highly enriched CML stem cells and mature cell populations in vitro. This protocol provides a 2.5 pg/nl limit of protein detection (<0.2% of a stem cell sample containing <104 cells). Additional assays are described for phosphorylated tyrosine 207 (pTyr207)-​CrkL and the protein tyrosine phosphatase ​PTPRC/​CD45; these assays were developed using this protocol and applied to CML patient samples. This method is of high throughput, and it can act as a screen for in vitro cancer stem cell response to drugs and novel agents

Nitrogen cycling, forest canopy reflectance, and emergent properties of ecosystems

In Ollinger et al. (1), we reported that mass-based concentrations of nitrogen in forest canopies (%N) are positively associated with whole-canopy photosynthetic capacity and canopy shortwave albedo in temperate and boreal forests, the latter result stemming from a positive correlation between %N and canopy near infrared (NIR) reflectance. This finding is intriguing because a functional link between %N and NIR reflectance could indicate an influence of nitrogen cycling on surface energy exchange, and could provide a means for estimating %N using broad-band satellite sensors

Public Performance Metrics: Driving Physician Motivation and Performance

Introduction: As providers transition from “fee-for-service” to “pay-for-performance” models, focus has shifted to improving performance. This trend extends to the emergency department (ED) where visits continue to increase across the United States. Our objective was to determine whether displaying public performance metrics of physician triage data could drive intangible motivators and improve triage performance in the ED.Methods: This is a single institution, time-series performance study on a physician-in-triage system. Individual physician baseline metrics—number of patients triaged and dispositioned per shift—were obtained and prominently displayed with identifiable labels during each quarterly physician group meeting. Physicians were informed that metrics would be collected and displayed quarterly and that there would be no bonuses, punishments, or required training; physicians were essentially free to do as they wished. It was made explicit that the goal was to increase the number triaged, and while the number dispositioned would also be displayed, it would not be a focus, thereby acting as this study’s control. At the end of one year, we analyzed metrics.Results: The group’s average number of patients triaged per shift were as follows: Q1-29.2; Q2-31.9; Q3-34.4; Q4-36.5 (Q1 vs Q4, p < 0.00001). The average numbers of patients dispositioned per shift were Q1-16.4; Q2-17.8; Q3-16.9; Q4-15.3 (Q1 vs Q4, p = 0.14). The top 25% of Q1 performers increased their average numbers triaged from Q1-36.5 to Q4-40.3 (ie, a statistically insignificant increase of 3.8 patients per shift [p = 0.07]). The bottom 25% of Q1 performers, on the other hand, increased their averages from Q1-22.4 to Q4-34.5 (ie, a statistically significant increase of 12.2 patients per shift [p = 0.0013]).Conclusion: Public performance metrics can drive intangible motivators (eg, purpose, mastery, and peer pressure), which can be an effective, low-cost strategy to improve individual performance, achieve institutional goals, and thrive in the pay-for-performance era