Best practices in prediction for decision-making : lessons from the atmospheric and earth sciences

Predictions that result from scientific research hold great appeal for decision-makers who are grappling with complex and controversial environmental issues, by promising to enhance their ability to determine a need for and outcomes of alternative decisions. A problem exists in that decision-makers and scientists in the public and private sectors solicit, produce, and use such predictions with little understanding of their accuracy or utility, and often without systematic evaluation or mechanisms of accountability. In order to contribute to a more effective role for ecological science in support of decision-making, this paper discusses three ``best practices'' for quantitative ecosystem modeling and prediction gleaned from research on modeling, prediction, and decision-making in the atmospheric and earth sciences. The lessons are distilled from a series of case studies and placed into the specific context of examples from ecological science

Adjustment and Sensitivity Analyses of a Beta Global Rangeland Model

G-Range is a global model that simulates generalized changes in rangelands through time, created with support from the International Livestock Research Institute. Spatial data and a set of parameters that control plant growth and other ecological attributes in landscape units combine with computer code to represent ecological process such as soil nutrient and water dynamics, vegetation growth, fire, and wild and domestic animal offtake. The model is spatial, with areas of the world divided into square cells

Wearable Knee Health Rehabilitation Assessment using Acoustical Emissions

Each year, approximately 200,000 Americans endure anterior cruciate ligament (ACL) tears, and 100,000 reconstructive procedures are conducted to repair the injured knees (1). The injury itself, and the long rehabilitation process that follows, can majorly disrupt the quality of life for these Americans through missed workdays, reduction of overall physical activity, and increased risk of re-injury in future activities. Wearable technologies for quantifying the state of rehabilitation, and providing feedback to the user regarding which activities or intensities of activities are safe to perform at any given time, could potentially help accelerate the rehabilitation process as well as reduce the risk of re-injury. Our lab has developed a novel, wearable sensing system based on miniature piezoelectric contact microphones for measuring the acoustical emissions from the knee during movements such as unloaded flexion / extension, sit-to-stand, and walking activities. The system consists of two Knowles BU-23173 contact microphones (Knowles, Itasca, IL) positioned on the medial and lateral sides of the patella, connected to custom, analog pre-amplifier circuits and a microcontroller for digitization and data storage on a secure digital (SD) card. In addition to the acoustical sensing, the system includes two integrated inertial measurement sensors including accelerometer and gyroscope modalities to enable joint angle calculations; these sensors, with digital outputs, are connected directly to the same microcontroller via serial peripheral interface (SPI). The system provides low noise, accurate joint acoustical emission and angle measurements in a wearable form factor, and has several hours of battery life. We have also taken measurements from healthy subjects, and athletes following acute ACL tear, to determine initial features from these acoustical emissions that are associated with injured versus healthy joints. We have found that the main acoustic clicks during particular motions occurred at consistent joint angles for healthy subjects based on intraclass correlation coefficient analysis (ICC(1,1) = 0.94 and ICC(1,k) = 0.99) (2). For one subject with an ACL tear, we found that the consistency of the joint acoustical emissions was lower for the injured knee as compared to the healthy knee in the recording immediately following the injury (\u3c 7 days), and improved following six months of rehabilitation. We envision using the wearable system we have recently completed to conduct further experiments with subjects following acute ACL tears, and tracking the progress of the rehabilitation while simultaneously measuring acoustical emissions in the context of particular movements. This data will then serve as a foundation for creating subject-specific algorithms for assessing rehabilitation and providing feedback to the users

The MMP-1/PAR-1 Axis Enhances Proliferation and Neuronal Differentiation of Adult Hippocampal Neural Progenitor Cells

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that play a role in varied forms of developmental and postnatal neuroplasticity. MMP substrates include protease-activated receptor-1 (PAR-1), a G-protein coupled receptor expressed in hippocampus. We examined proliferation and differentiation of adult neural progenitor cells (aNPCs) from hippocampi of mice that overexpress the potent PAR-1 agonist MMP-1. We found that, as compared to aNPCs from littermate controls, MMP-1 tg aNPCs display enhanced proliferation. Under differentiating conditions, these cells give rise to a higher percentage of MAP-2+ neurons and a reduced number of oligodendrocyte precursors, and no change in the number of astrocytes. The fact that these results are MMP and PAR-1 dependent is supported by studies with distinct antagonists. Moreover, JSH-23, an inhibitor of NF-κB p65 nuclear translocation, counteracted both the proliferation and differentiation changes seen in MMP-1 tg-derived NPCs. In complementary studies, we found that the percentage of Sox2+ undifferentiated progenitor cells is increased in hippocampi of MMP-1 tg animals, compared to wt mice. Together, these results add to a growing body of data suggesting that MMPs are effectors of hippocampal neuroplasticity in the adult CNS and that the MMP-1/PAR-1 axis may play a role in neurogenesis following physiological and/or pathological stimuli

Stability of bimetallic Pd-Zn catalysts for the steam reforming of methanol

ZnO-supported palladium-based catalysts have been shown in recent years to be both active and selective towards the steam reforming of methanol, although they are still considered to be less active than traditional copper-based catalysts. The activity of PdZn catalysts can be significantly improved by supporting them on alumina. Here we show that the Pd/ZnO/Al2O3 catalysts have better long-term stability when compared with commercial Cu/ZnO/Al2O3 catalysts, and that they are also stable under redox cycling. The Pd/ZnO/Al2O3 catalysts can be easily regenerated by oxidation in air at 420 °C followed by re-exposure to reaction conditions at 250 °C, while the Cu/ZnO based catalysts do not recover their activity after oxidation. Reduction at high temperatures (>420 °C) leads to Zn loss from the alloy nanoparticle surface resulting in a reduced catalyst activity. However, even after such extreme treatment, the catalyst activity is regained with time on stream under reaction conditions alone, leading to highly stable catalysts. These findings illustrate that the nanoparticle surface is dynamic and changes drastically depending on the environment, and that elevated reduction temperatures are not necessary to achieve high CO2 selectivity

Familiarity Differentially Affects Right Hemisphere Contributions to Processing Metaphors and Literals

The role of the two hemispheres in processing metaphoric language is controversial. While some studies have reported a special role of the right hemisphere (RH) in processing metaphors, others indicate no difference in laterality relative to literal language. Some studies have found a role of the RH for novel/unfamiliar metaphors, but not conventional/familiar metaphors. It is not clear, however, whether the role of the RH is specific to metaphor novelty, or whether it reflects processing, reinterpretation or reanalysis of novel/unfamiliar language in general. Here we used functional magnetic resonance imaging (fMRI) to examine the effects of familiarity in both metaphoric and non-metaphoric sentences. A left lateralized network containing the middle and inferior frontal gyri, posterior temporal regions in the left hemisphere (LH), and inferior frontal regions in the RH, was engaged across both metaphoric and non-metaphoric sentences; engagement of this network decreased as familiarity decreased. No region was engaged selectively for greater metaphoric unfamiliarity. An analysis of laterality, however, showed that the contribution of the RH relative to that of LH does increase in a metaphor-specific manner as familiarity decreases. These results show that RH regions, taken by themselves, including commonly reported regions such as the right inferior frontal gyrus (IFG), are responsive to increased cognitive demands of processing unfamiliar stimuli, rather than being metaphor-selective. The division of labor between the two hemispheres, however, does shift towards the right for metaphoric processing. The shift results not because the RH contributes more to metaphoric processing. Rather, relative to its contribution for processing literals, the LH contributes less

The MMP-1/PAR-1 Axis Enhances Proliferation and Neuronal Differentiation of Adult Hippocampal Neural Progenitor Cells

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that play a role in varied forms of developmental and postnatal neuroplasticity. MMP substrates include protease-activated receptor-1 (PAR-1), a G-protein coupled receptor expressed in hippocampus. We examined proliferation and differentiation of adult neural progenitor cells (aNPCs) from hippocampi of mice that overexpress the potent PAR-1 agonist MMP-1. We found that, as compared to aNPCs from littermate controls, MMP-1 tg aNPCs display enhanced proliferation. Under differentiating conditions, these cells give rise to a higher percentage of MAP-2+ neurons and a reduced number of oligodendrocyte precursors, and no change in the number of astrocytes. The fact that these results are MMP and PAR-1 dependent is supported by studies with distinct antagonists. Moreover, JSH-23, an inhibitor of NF-κB p65 nuclear translocation, counteracted both the proliferation and differentiation changes seen in MMP-1 tg-derived NPCs. In complementary studies, we found that the percentage of Sox2+ undifferentiated progenitor cells is increased in hippocampi of MMP-1 tg animals, compared to wt mice. Together, these results add to a growing body of data suggesting that MMPs are effectors of hippocampal neuroplasticity in the adult CNS and that the MMP-1/PAR-1 axis may play a role in neurogenesis following physiological and/or pathological stimuli