When subjected to an appropriate asymmetric stimulus, seedlings of Bidens pilosa L. "store" a symmetry-breaking instruction that will finally take effect (in the form of a differential growth of the cotyledonary buds) only if the plants are in a state in which they can "recall" this information. The ability of the plants to recall the stored symmetry-breaking instruction may be switched "on" or "off" by the application of a variety of stimuli. Although its detailed phenomenology is rather complicated, the overall behaviour of the plant storage/recall system can be modelled by use of an asynchronous, logical (discrete) description involving positive and negative feedback circuits, which are required for the existence of multi-stationarity and stability, respectively. The state tables, as used in this formalism, give a concise and easy-to-handle description of the evolution of the system and make it particularly easy to determine its stable states. This modelling approach may be extended to the formulation of many other experimental systems.
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http://dx.doi.org/10.1055/s-2004-821090 | DOI Listing |
ISA Trans
January 2025
Departamento de Ingeniería Eléctrica, CINVESTAV, CDMX, Mexico. Electronic address:
In control system design, managing measurement noise is a critical challenge, requiring a balance between responsiveness and noise suppression. Traditional methods often involve trade-offs, compromising either aspect. This paper proposes a novel solution by integrating a Finite Impulse Response (FIR) filter within the discrete controller transfer function, coupled with disturbance rejection through the Internal Model Principle (IMP).
View Article and Find Full Text PDFStud Hist Philos Sci
December 2024
Freudental Institute, Department of Mathematics, Faculty of Science, Utrecht University, The Netherlands. Electronic address:
This paper is a critical analysis of the structure of the quantum revolution. I consider the factual question of how, historically and theoretically, the classical gave way to the quantum, and I argue for an answer that shows, contra Thomas Kuhn's influential philosophy of science, that it is the logic, and not the sociology and psychology, of research that correctly explains the classical-to-the-quantum paradigm shift. My approach is based not on archival studies but on a careful reading, in their original historical context, of Max Planck's and Albert Einstein's well-known papers; the burden of my argument, which at points will be outspoken, consists, then, in identifying and removing the impediments that prevent us from reading these papers in themselves.
View Article and Find Full Text PDFSoc Sci Med
December 2024
Département de gestion, Evaluation et politique de santé, School of Public Health, University of Montreal, Montreal, QC, Canada; CR-IUSMM, CIUSSS de l'Est de l'Île de Montréal, 7101 Parc Avenue, Montreal, QC, H3N 1X9, Canada.
Objective: To develop a value set for the Short-Form 6-Dimension version 2 (SF-6Dv2) by incorporating societal preferences obtained from three distinct approaches: Standard Gamble (SG), composite Time Trade-Off (cTTO), and Discrete Choice Experiment (DCE).
Methods: Data were gathered from the general population of Quebec, Canada, using the standardized valuation protocol developed by EuroQol for the cTTO and DCE tasks, as well as the valuation protocol developed by Sheffield University for the SG. The SG and cTTO data were analyzed using OLS, GLS, GLS Tobit, and heteroskedastic Tobit models.
Neuron
December 2024
Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA. Electronic address:
Motor output results from the coordinated activity of neural circuits distributed across multiple brain regions that convey information to the spinal cord via descending motor pathways. Yet the organizational logic through which supraspinal systems target discrete components of spinal motor circuits remains unclear. Here, using viral transsynaptic tracing along with serial two-photon tomography, we have generated a whole-brain map of monosynaptic inputs to spinal V1 interneurons, a major inhibitory population involved in motor control.
View Article and Find Full Text PDFMath Biosci
December 2024
Department of Theoretical Biology, Max Planck Institute for Evolutionary Biology, August-Thienemann-Str. 2, Plön 24306, Germany. Electronic address:
Lobular carcinoma in situ (LCIS) is a precursor of invasive lobular carcinoma of the breast. LCIS cells lack cell-cell cohesion due to the loss of E-cadherin. LCIS cells grow in mammary lobules rather than in ducts.
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