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Wind routinely topples trees during storms, and the likelihood that a tree is toppled depends critically on its allometry. Yet none of the existing theories to explain tree allometry consider wind drag on tree canopies. Since leaf area index in crowded, self-thinning stands is independent of stand density, the drag force per unit land can also be assumed to be independent of stand density, with only canopy height influencing the total toppling moment. Tree stem dimensions and the self-thinning biomass can then be computed by further assuming that the risk of toppling over and stem maintenance per unit land area are independent of stand density, and that stem maintenance cost is a linear function of stem surface area and sapwood volume. These assumptions provide a novel way to understand tree allometry and lead to a self-thinning line relating tree biomass and stand density with a power between -3/2 and -2/3 depending on the ratio of maintenance of sapwood and stem surface.
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http://dx.doi.org/10.1016/j.jtbi.2010.04.021 | DOI Listing |
Exp Appl Acarol
September 2025
Julius Kühn-Institut, Institute for Plant Protection in Horticulture and Urban Green, Messeweg 11/12, 38104, Braunschweig, Germany.
The tomato russet mite, Aculops lycopersici (Tryon), is a key pest of commercially grown tomatoes worldwide. Due to its minute size, its detection is often not timely for effective control. In this study, the approach of limiting A.
View Article and Find Full Text PDFmBio
September 2025
Department of Microbiology, Oregon State University, Corvallis, Oregon, USA.
Quorum sensing (QS) is a widespread signaling mechanism in bacteria that coordinates collective behaviors according to population density. A foundational assumption in this field is that QS functions as a gene expression switch that synchronizes responses at the population level. While some studies indeed report homogeneous on/off transitions, others report heterogeneity at the cellular level, challenging the canonical view.
View Article and Find Full Text PDFOsteoporos Int
September 2025
Clinical Epidemiology Research Unit, Hospital Infantil de Mexico "Federico Gomez", Mexico City, Mexico.
Purpose: Conduct an overview of systematic reviews of the current fracture risk prediction tools in use.
Material And Methods: We included systematic reviews (SRs) that assessed the predictive ability of any tool, score, algorithm, or other instrument for fracture risk. The primary outcome measure was the area under the curve (AUC) representing predicted fracture risk within a specified timeframe obtained from receiver operating characteristic (ROC) analysis.
J Colloid Interface Sci
September 2025
State Key Laboratory of Heavy Oil Processing, China University of Petroleum (Beijing), Changping, 102249, China. Electronic address:
Carbon-based catalysts with free-standing structure are essential for rechargeable zinc-air battery as electrodes, which can avoid the side effects brought by organic binder. However, the current preparation methods still can be improved for faster preparation process and morphology control. In this study, we reported a fabrication strategy of self-standing carbon catalyst loaded with CoFe nanoparticles and carbon nanotube as air electrodes for liquid rechargeable zinc-air battery.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
September 2025
State Key Laboratory of High Pressure and Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China.
Solid-state lithium-ion batteries have raised considerable attention due to their great potential for the development of new energy storage devices with high energy density and safety. However, enhancing ion conductivity in solid-state electrolytes stands as a pivotal challenge for the large-scale commercialization of next-generation lithium-ion batteries. Here, a high-pressure strategy is reported to achieve the significant enhancement of lithium-ion conductivity by 2 orders of magnitude and the disappearance of grain boundary resistance in polyoxometalate LiPWO electrolyte via an irreversible phase transition from Keggin to bronze structure.
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