This paper proposes and studies a comprehensive control model that considers fish population density and its current growth rate, providing new ideas for fishing strategies. First, we established a phytoplankton-fish model with state-impulse feedback control based on fish density and rate of change. Secondly, the complex phase sets and impulse sets of the model are divided into three cases, then the Poincaré map of the model is defined and its complex dynamic properties are deeply studied. Furthermore, some necessary and sufficient conditions for the global stability of the fixed point (order-1 limit cycle) have been provided even for the Poincaré map. The existence conditions for periodic solutions of order-k(k≥2) are discussed, and the influence of dynamic thresholds on system dynamics is shown. Dynamic thresholds depend on fish density and rate of change, i.e., the form of control employed is more in line with the evolution of biological populations than in earlier studies. The analytical method presented in this paper also plays an important role in analyzing impulse models with complex phase sets or impulse sets.
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http://dx.doi.org/10.3934/mbe.2023352 | DOI Listing |
J Ren Nutr
January 2025
Division of Nephrology Universidade Federal de São Paulo, São Paulo, Brazil; Nutrition Program, Universidade Federal de São Paulo, São Paulo, Brazil. Electronic address:
Objective: To evaluate the associations between the quality of the diet and its components and microbial diversity and composition in peritoneal dialysis (PD) patients.
Design And Methods: This crossectional study included PD patients for at least 3 months, aged 18-75 years and clinically stable. The Diet Quality Index (DQI), validated for the Brazilian population, is based on the energy density of 11 components ("sugar and sweets"; "beef, pork and processed meat"; "refined grains and breads"; "animal fat"; "poultry, fish and eggs"; "whole cereals, tubers and roots"; "fruits"; "non-starch vegetables"; "legumes and nuts"; "milk and dairy products"; "vegetable oil").
Sci Rep
January 2025
Hangzhou Academy of Agricultural Sciences, Hangzhou, 310024, China.
Artificial fish nests are common tools in fisheries management, providing spawning grounds to enhance the size and diversity of fish populations. This study aimed to explore the effects of deployment locations on the reproductive efficiency and preferences of fish with adhesive and demersal eggs using artificial nests. Floating artificial nests were deployed in three regions (upstream, midstream, and downstream) of a reservoir in Zhejiang, China, at locations with three topographical types: steep slope (reservoir shore, slopes > 60°), gentle slope (reservoir shore, slopes < 30°), and confluence (middle thread of channel).
View Article and Find Full Text PDFNutrients
January 2025
Internal Medicine and Stroke Care Ward, Department of Promoting Health, Maternal-Infant, Excellence and Internal and Specialized Medicine (Promise) G. D'Alessandro, University of Palermo, 90127 Palermo, Italy.
Metabolic syndrome is a cluster of risk factors, including abdominal obesity, insulin resistance, hypertension, dyslipidemia (intended as an increase in triglyceride levels and a reduction in HDL cholesterol levels), and elevated fasting glucose, that increase the risk of cardiovascular disease and type 2 diabetes. With the rising prevalence of metabolic syndrome, effective dietary interventions are essential in reducing these health risks. The Mediterranean diet, rich in fruits, vegetables, whole grains, legumes, nuts, and olive oil and moderate in fish and poultry, has shown promise in addressing metabolic syndrome and its associated components.
View Article and Find Full Text PDFInsects
December 2024
Environmental Health and Ecological Sciences Department, Ifakara Health Institute, Morogoro P.O. Box 53, Tanzania.
Interspecific competition between mosquito larvae may affects adult vectorial capacity, potentially reducing disease transmission. It also influences population dynamics, and cannibalistic and predatory behaviors. However, knowledge of interspecific competition between and species is limited.
View Article and Find Full Text PDFAnimals (Basel)
January 2025
College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China.
This research aimed to explore the impact of tea polyphenol (TP) supplementation on the development, antioxidant properties, immune responses, and gut wellness in largemouth bass (, LMB). Four diets with varying levels of TPs (0.00%, 0.
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