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The long-term interaction between human activity and climate is subject to increasing scrutiny. Humans homogenize landscapes through deforestation, agriculture, and burning and thereby might reduce the capacity of landscapes to provide archives of climate change. Alternatively, land-use change might overwhelm natural buffering and amplify latent climate signals, rendering them detectable. Here we examine a sub-annually resolved sedimentary record from Lake Sauce in the western Amazonian lowlands that spans 6900 years. Finely-laminated sediments were deposited from ca. 5000 years ago until the present, and human activity in the watershed was revealed through the presence of charcoal and maize agriculture. The laminations, analyzed for color content and bandwidth, showed distinctive changes that were coupled to more frequent occurrence of fossil maize pollen. As agricultural activity intensified ca. 2200 cal. BP, the 2- to 8-year periodicity characteristic of El Niño-Southern Oscillation became evident in the record. These agricultural activities appeared to have amplified an existing, but subtle climatic signal that was previously absorbed by natural vegetation. When agricultural activity slowed, or land use around Lake Sauce changed at ca. 800 cal. BP, the signal of El Niño-Southern Oscillation (ENSO) activity became erratic.
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http://dx.doi.org/10.1111/gcb.13608 | DOI Listing |
Fungal Biol
October 2025
Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA. Electronic address:
In many model organisms, the circadian system has been proposed to comprise multiple oscillators that interact to promote accuracy of the clock as well as intricacies of rhythmic outputs. In Neurospora crassa, the circadian transcriptional/translational loop comprising of the FRQ (Frequency) and WCC (White Collar Complex) proteins has been instrumental in explaining many attributes of the clock including entrainment and rhythms in development and gene expression; in addition, some non-circadian oscillations can be unmasked when the FRQ-WCC feedback loop is eliminated. These rhythms have often lost defining circadian characteristics and are potentially controlled by other oscillators, termed FRQ-less oscillators (FLOs) in Neurospora.
View Article and Find Full Text PDFUltrasonics
September 2025
Paderborn University, Paderborn, Germany.
This study investigates the phenomenon of mode repulsion in Lamb waves propagating through two coupled plates with an elastic interface. Using a spring-based coupling model and the Scaled Boundary Finite Element Method, the dispersion curves of the coupled system are analyzed under various interface conditions-weak coupling, sliding boundary, and perfect coupling. This research highlights how the mechanical stiffness of the interface influences the separation of modes and the emergence of repulsion regions.
View Article and Find Full Text PDFComput Biol Med
September 2025
Laboratorio de Procesado de Imagen (LPI), ETSI Telecomunicación, Universidad de Valladolid, Valladolid, Spain. Electronic address:
Modelling the diffusion-relaxation magnetic resonance (MR) signal obtained from multi-parametric sequences has recently gained immense interest in the community due to new techniques significantly reducing data acquisition time. A preferred approach for examining the diffusion-relaxation MR data is to follow the continuum modelling principle that employs kernels to represent the tissue features, such as the relaxations or diffusion properties. However, constructing reasonable dictionaries with predefined signal components depends on the sampling density of model parameter space, thus leading to a geometrical increase in the number of atoms per extra tissue parameter considered in the model.
View Article and Find Full Text PDFComput Biol Chem
September 2025
Department of Mathematics, Gour Mahavidyalaya, Malda 732142, India. Electronic address:
This research proposes an advanced technique to manipulating milk flow and its thermal characteristics through a dynamic electromagnetic pathway, effectively managing the non-linear thermal behavior of milk. This study employs advanced artificial intelligence (AI) to create a sophisticated analytical framework for modeling the complex interactions between milk flow, hybrid nanoparticles (Ag-ZnO), and dynamic thermal conditions in a squarely activated electromagnetic tunnel. The research focuses on optimizing key steps in dairy manufacturing-microbial reduction and texture stabilization by analyzing the behavior of Ag-ZnO/milk under oscillating thermal amplification, incorporating radiant heat and Darcy drag effects.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
September 2025
Department of Biomechanical Engineering, Faculty of Engineering Technology, University of Twente, Enschede, 7522 NB, the Kingdom of the Netherlands. Electronic address:
In orthopaedic surgical procedures, bone cutting is often performed with an oscillating saw. Achieving an optimal cut requires high accuracy, low temperature, minimal surgeon effort, and time efficiency, all of which may be influenced by the forces applied on the sawing device, and the microstructure of the cut bone. The relation between bovine bone microstructure and sawing forces has been studied.
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