Feedback loop dominance analysis of two tree mortality models: relationship between structure and behavior

Abstract Background Predictive models of post-fire tree and stem mortality are vital for management planning and understanding fire effects. Post-fire tree and stem mortality have been traditionally modeled as a simple empirical function of tree defenses (e.g., bark thickness) and fire injury (e.g., crown scorch). We used the Fire and Tree Mortality database (FTM)—which includes observations of tree mortality in obligate seeders and stem mortality in basal resprouting species from across the USA—to evaluate the accuracy of post-fire mortality models used in the First Order Fire Effects Model (FOFEM) software system. The basic model in FOFEM, the Ryan and Amman (R-A) model, uses bark thickness and percentage of crown volume scorched to predict post-fire mortality and can be applied to any species for which bark thickness can be calculated (184 species-level coefficients are included in the program). FOFEM (v6.7) also includes 38 species-specific tree mortality models (26 for gymnosperms, 12 for angiosperms), with unique predictors and coefficients. We assessed accuracy of the R-A model for 44 tree species and accuracy of 24 species-specific models for 13 species, using data from 93 438 tree-level observations and 351 fires that occurred from 1981 to 2016. Results For each model, we calculated performance statistics and provided an assessment of the representativeness of the evaluation data. We identified probability thresholds for which the model performed best, and the best thresholds with either ≥80% sensitivity or specificity. Of the 68 models evaluated, 43 had Area Under the Receiver Operating Characteristic Curve (AUC) values ≥0.80, indicating excellent performance, and 14 had AUCs <0.7, indicating poor performance. The R-A model often over-predicted mortality for angiosperms; 5 of 11 angiosperms had AUCs <0.7. For conifers, R-A over-predicted mortality for thin-barked species and for small diameter trees. The species-specific models had significantly higher AUCs than the R-A models for 10 of the 22 models, and five additional species-specific models had more balanced errors than R-A models, even though their AUCs were not significantly different or were significantly lower. Conclusions Approximately 75% of models tested had acceptable, excellent, or outstanding predictive ability. The models that performed poorly were primarily models predicting stem mortality of angiosperms or tree mortality of thin-barked conifers. This suggests that different approaches—such as different model forms, better estimates of bark thickness, and additional predictors—may be warranted for these taxa. Future data collection and research should target the geographical and taxonomic data gaps and poorly performing models identified in this study. Our evaluation of post-fire tree mortality models is the most comprehensive effort to date and allows users to have a clear understanding of the expected accuracy in predicting tree death from fire for 44 species.

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Trust motivation: The self-regulatory processes underlying trust decisions

Organizational Psychology Review ◽

10.1177/2041386619873616 ◽

2019 ◽

Vol 9 (2-3) ◽

pp. 99-123 ◽

Cited By ~ 4

Author(s):

Lisa van der Werff ◽

Alison Legood ◽

Finian Buckley ◽

Antoinette Weibel ◽

David de Cremer

Keyword(s):

Goal Setting ◽

Feedback Loop ◽

Future Research ◽

Two Phase ◽

Cognitive Trust ◽

Regulatory Processes ◽

Dynamic View ◽

Definition Of ◽

And Behavior ◽

And Control

Theorizing about trust has focused predominantly on cognitive trust cues such as trustworthiness, portraying the trustor as a relatively passive observer reacting to the attributes of the other party. Using self-determination and control theories of motivation, we propose a model of trust motivation that explores the intraindividual processes involved in the volitional aspects of trust decision-making implied by the definition of trust as a willingness to be vulnerable. We distinguish between intrinsic and extrinsic drivers of trust and propose a two-phase model of trust goal setting and trust regulation. Our model offers a dynamic view of the trusting process and a framework for understanding how trust cognition, affect and behavior interact over time. Furthermore, we discuss how trust goals may be altered or abandoned via a feedback loop during the trust regulation process. We conclude with a discussion of potential implications for existing theory and future research.

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A Robust Model for Circadian Redox Oscillations

10.1101/590570 ◽

2019 ◽

Cited By ~ 1

Author(s):

Marta del Olmo ◽

Achim Kramer ◽

Hanspeter Herzel

Keyword(s):

Negative Feedback ◽

Feedback Loop ◽

Redox State ◽

Design Principle ◽

Quantitative Description ◽

Daily Rhythms ◽

Basic Principles ◽

Robust Model ◽

Brown Adipose ◽

And Behavior

AbstractThe circadian clock is an endogenous oscillator that controls daily rhythms in metabolism, physiology and behavior. Although the timekeeping components differ among species, a common design principle is a transcription-translation negative feedback loop. However, it is becoming clear that other mechanisms can contribute to the generation of 24 h rhythms. In mammalian adrenal gland, heart and brown adipose tissue, peroxiredoxins (Prx) exhibit 24 h rhythms in their redox state. Such rhythms are generated as a result of an inactivating hyperoxidation reaction that is reduced by coordinated import of the sulfiredoxin (Srx) into the mitochondria. However, a quantitative description of the Prx/Srx oscillating system is still missing. We investigate the basic principles that generate mitochondrial Prx/Srx rhythms using computational modeling. We observe that the previously described delay in mitochondrial Srx import, in combination with an appropriate separation of fast and slow reactions is sufficient to generate robust self-sustained relaxation-like oscillations. We find that our conceptual model can be regarded as a series of three consecutive phases and two temporal switches, highlighting the importance of delayed negative feedback and switches in the generation of oscillations.

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How do tree mortality models from combined tree-ring and inventory data affect projections of forest succession?

Forest Ecology and Management ◽

10.1016/j.foreco.2018.11.042 ◽

2019 ◽

Vol 433 ◽

pp. 606-617 ◽

Cited By ~ 9

Author(s):

Marco Vanoni ◽

Maxime Cailleret ◽

Lisa Hülsmann ◽

Harald Bugmann ◽

Christof Bigler

Keyword(s):

Tree Ring ◽

Tree Mortality ◽

Forest Succession ◽

Inventory Data ◽

Mortality Models

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The Effect of a Quality Improvement Feedback Loop on Paramedic Skills, Charting, and Behavior

Prehospital and Disaster Medicine ◽

10.1017/s1049023x00040814 ◽

1994 ◽

Vol 9 (1) ◽

pp. 35-38 ◽

Cited By ~ 14

Author(s):

Robert E. O'Connor ◽

Ross E. Megargel

Keyword(s):

Cardiac Arrest ◽

Quality Improvement ◽

Success Rate ◽

Endotracheal Intubation ◽

Feedback Loop ◽

Psychomotor Skills ◽

Success Rates ◽

New Castle County ◽

And Behavior ◽

The Impact

AbstractObjective:A mechanism was initiated for conveying quality improvement (QI) results to paramedics as a means of improving chart documentation in difficult-to-correct areas. This study examines the impact of this QI feedback loop on charting, resuscitation rates from cardiac arrest, endotracheal intubation (ETI) success rates, and trauma scene times.Design:Paramedic trip sheets were reviewed before and after the institution of the QI feedback hop in this interrupted time series design.Setting:The New Castle County, Delaware, Paramedic Program.Participants:All New Castle County paramedics participated in the study.Interventions:In January 1990, the medical director began to circulate a QI summary among the paramedics in an effort to improve performance and chart documentation. The summary focused on the management of respiratory distress or arrest, cardiac arrest, and major trauma. The success rate for ETI was compared with the rate of field resuscitation from cardiac arrest, the percentage of unjustified prolonged trauma scene times (longer than 10 minutes), and the percent compliance with minimum endotracheal intubation documetation (ETID) requirements from a six-month period before institution of the QI feedback mechanism with data obtained from a six-month period after the program had been operational for one year.Results:Comparing results from before with after the initiation of the QI program, the ETI success rate was 273 of 295 (92.5%) before and 300 of 340 (88.2%) after (X2 = 3.04, p <.1, ns); field resuscitations totaled 26 of 187 (13.9%) before and 44 of 237 (18.6) after (X2 = 1.40, p <.25, ns); ETID rate was 249 of 295 (84.4%) before and 336 of 340 (98.8%) after (X2 = 44.24, p <.001), and unjustified prolonged trauma scene times were 69 of 278 (24.8%) before and seven of 501 (1.4%) after (X2 = 320.5, p <.001).Conclusion:The use of QI feedback had little effect on psychomotor skills such as the ETI success rate or resuscitation rate, but had a dramatic effect on chart documentation, as evidenced by ETID rate, and behavior, as evidenced by the reduction in prolonged trauma scene times. The use of QI feedback is recommended as a means of correcting charting deficiencies or modifying behavior.

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Climatic information improves statistical individual-tree mortality models for three key species of Sichuan Province, China

Annals of Forest Science ◽

10.1007/s13595-014-0449-2 ◽

2015 ◽

Vol 72 (4) ◽

pp. 443-455 ◽

Cited By ~ 1

Author(s):

Shuai Qiu ◽

Ming Xu ◽

Renqiang Li ◽

Yunpu Zheng ◽

Daniel Clark ◽

...

Keyword(s):

Tree Mortality ◽

Sichuan Province ◽

Individual Tree ◽

Mortality Models ◽

Key Species ◽

Climatic Information

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Towards a common methodology for developing logistic tree mortality models based on ring-width data

Ecological Applications ◽

10.1890/15-1402.1 ◽

2016 ◽

Vol 26 (6) ◽

pp. 1827-1841 ◽

Cited By ~ 21

Author(s):

Maxime Cailleret ◽

Christof Bigler ◽

Harald Bugmann ◽

Jesús Julio Camarero ◽

Katarina Cˇufar ◽

...

Keyword(s):

Tree Mortality ◽

Ring Width ◽

Mortality Models

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Developing post-fire Eucalyptus globulus stand damage and tree mortality models for enhanced forest planning in Portugal

Silva Fennica ◽

10.14214/sf.32 ◽

2011 ◽

Vol 45 (1) ◽

Cited By ~ 17

Author(s):

Susete Marques ◽

Jordi Garcia-Gonzalo ◽

José Borges ◽

Brigite Botequim ◽

M. Oliveira ◽

...

Keyword(s):

Eucalyptus Globulus ◽

Tree Mortality ◽

Forest Planning ◽

Mortality Models ◽

Stand Damage

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How to predict tree death from inventory data — lessons from a systematic assessment of European tree mortality models

Canadian Journal of Forest Research ◽

10.1139/cjfr-2016-0224 ◽

2017 ◽

Vol 47 (7) ◽

pp. 890-900 ◽

Cited By ~ 15

Author(s):

Lisa Hülsmann ◽

Harald Bugmann ◽

Peter Brang

Keyword(s):

Tree Growth ◽

Tree Mortality ◽

Model Performance ◽

High Temporal Resolution ◽

Forest Reserves ◽

Individual Level ◽

Systematic Assessment ◽

Influence Model ◽

Mortality Models ◽

The Individual

The future development of forest ecosystems depends critically on tree mortality. However, the suitability of empirical mortality algorithms for extrapolation in space or time remains untested. We systematically analyzed the performance of 46 inventory-based mortality models available from the literature using nearly 80 000 independent records from 54 strict forest reserves in Germany and Switzerland covering 11 species. Mortality rates were predicted with higher accuracy if covariates for tree growth and (or) competition at the individual level were included and if models were applied within the same ecological zone. In contrast, classification of dead vs. living trees was only improved by growth variables. Management intensity in the calibration stands, as well as the census interval and size of the calibration datasets, did not influence model performance. Consequently, future approaches should make use of tree growth and competition at the level of individual trees. Mortality algorithms for applications over a restricted spatial extent and under current climate should be calibrated based on datasets from the same region, even if they are small. To obtain models with wide applicability and enhanced climatic sensitivity, the spatial variability of mortality should be addressed explicitly by considering environmental influences using data of high temporal resolution covering large ecological gradients. Finally, such models need to be validated and documented thoroughly.

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