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1.
Food Microbiol ; 120: 104483, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38431328

RESUMO

Wooden vats are used in the production of some traditional cheeses as the biofilms on wooden vat surfaces are known to transfer large quantities of microbes to cheese. However, the safety of using wooden vats for cheese production remains controversial as the porous structure of wood provides an irregular surface that may protect any attached pathogen cells from cleaning and sanitation processes. On the other hand, the absence of pathogens in wooden vats has been reported in multiple studies and wooden materials have not been associated with foodborne illness outbreaks. The present study determined the survival of Listeria monocytogenes and Shiga toxin-producing Escherichia coli (STEC) during the production of an uncooked pressed cheese in wooden vats as well as their ability to transfer to the wood and then to milk used in subsequent batches of cheese production in the absence of formal cleaning. Results from the study indicate that pathogens inoculated in milk grew during production of the uncooked cheese, but showed limited ability to colonize the wooden vats and contaminate subsequent batches. These results suggest that the risks of using wooden vats to produce cheese is low if the milk is of high microbiological quality.


Assuntos
Queijo , Listeria monocytogenes , Escherichia coli Shiga Toxigênica , Animais , Queijo/microbiologia , Leite/microbiologia , Dinâmica Populacional , Microbiologia de Alimentos
2.
Afr J Reprod Health ; 28(2): 13-30, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38425044

RESUMO

Girls aged 10-19 currently represent 12% of Niger's population (2020). And this number continues to grow as the fertility rate is higher while mortality is declining faster. Using Niger's demographic and health surveys carried out between 1992 and 2012, the study investigated adolescent fertility, its trends and associated factors. It mobilised descriptive methods (Total cohort fertility in adolescence (TCFA) computation, distribution of the number of adolescent births, and computation of adolescent cohort childbearing mean age) and multivariate Logistic and Poisson models. The result shows the TCFA went from 1.29 in 1992 to 1.17 in 2012. Early sexual intercourse and marriage, infant mortality, the desire for a large family, and urbanisation are among the factors significantly associated with adolescent fertility in Niger. The study concludes that the high level of adolescent fertility in Niger does not seem to be changing.


Les adolescentes représentent 12 % de la population Nigerienne (2020). Ce chiffre continue de croître car la fécondité reste elevée alors que la mortalité diminue rapidement. Utilisant les enquêtes démographiques et de santé du Niger entre 1992 et 2012, cette étude s'est intéressée aux tendances et facteurs de la descendance finale à l'adolescence (DFA). Elle a mobilisé des méthodes descriptives (calcul de la DFA, distribution du nombre de naissances adolescentes, calcul de l'âge moyen à la maternité adolescente) et des modèles multivariés de régression logistique et de Poisson. Les résultats montrent que la DFA est passée de 1,29 en 1992 à 1,17 en 2012. Les rapports sexuels et le mariage précoces, la mortalité infantile, le désir d'une famille nombreuse et l'urbanisation sont parmi les facteurs significativement associés à la fécondité adolescente au Niger. L'étude conclut que le niveau élevé de la fécondité des adolescentes au Niger ne semble pas évoluer.


Assuntos
Coeficiente de Natalidade , Fertilidade , Lactente , Feminino , Adolescente , Humanos , Níger/epidemiologia , Dinâmica Populacional , Casamento , Inquéritos Epidemiológicos
3.
PLoS One ; 19(3): e0300343, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38466734

RESUMO

The purpose of this study is to explore the impact of GDP per capita income (GDPPCI), unemployment, higher education (HE), and economic growth (EG) on migration in Sri Lanka. Numerous global and local studies have explored the influence of macroeconomic and socioeconomic factors on migration. In the Sri Lankan context, fewer studies have probed the impact of GDPPCI, unemployment, HE, and EG on migration, particularly concerning brain drain and domestic labour market pressure. An applied research methodology was adopted, utilising annual data from 1986 to 2022. The statistical data were sourced from reports by the Sri Lanka Bureau of Foreign Employment (SLBFE), the Central Bank of Sri Lanka (CBSL), Labor Force Survey Data from the Department of Census and Statistics (LFSDCS), and University Grants Commissions (UGC). This study utilised the Vector Error Correlation model (VECM), Vector Auto-regression (VAR), and Granger Causality test through STATA. The empirical findings of the VAR model highlighted that GDPPCI and EG negatively impact migration, whereas unemployment and HE positively affect migration. The study's implications demonstrated that GDPPCI, unemployment, HE, and EG were the primary factors influencing the country's migration decisions. These findings will hopefully inform and guide the Sri Lankan government and policymakers for more effective decision-making.


Assuntos
Emigração e Imigração , Humanos , Demografia , Dinâmica Populacional , Sri Lanka , Fatores Socioeconômicos , Economia , Países em Desenvolvimento
4.
Proc Natl Acad Sci U S A ; 121(12): e2312207121, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38466852

RESUMO

Over the last 12,000 y, human populations have expanded and transformed critical earth systems. Yet, a key unresolved question in the environmental and social sciences remains: Why did human populations grow and, sometimes, decline in the first place? Our research builds on 20 y of archaeological research studying the deep time dynamics of human populations to propose an explanation for the long-term growth and stability of human populations. Innovations in the productive capacity of populations fuels exponential-like growth over thousands of years; however, innovations saturate over time and, often, may leave populations vulnerable to large recessions in their well-being and population density. Empirically, we find a trade-off between changes in land use that increase the production and consumption of carbohydrates, driving repeated waves of population growth over thousands of years, and the susceptibility of populations to large recessions due to a lag in the impact of humans on resources. These results shed light on the long-term drivers of human population growth and decline.


Assuntos
Crescimento Demográfico , Ciências Sociais , Humanos , Densidade Demográfica , Arqueologia , Dinâmica Populacional
5.
Inquiry ; 61: 469580241237106, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38462886

RESUMO

The relationship between women's working status and fertility behavior has been a topic of interest for researchers and policymakers. The societal shifts over time, particularly the increasing participation of women in the workforce, have transformed traditional roles. Women, once primarily perceived as caregivers, are now assuming roles of economic independence. This transformation prompts a re-evaluation of the traditional association between women's working status and fertility behavior. This study aims to investigate the impact of women's working status on fertility behavior using a multistage stratified sampling design. A total of 408 women aged 15 to 49 years were recruited from 2 strata: working and non-working women. The data were collected through face-to-face interviews using a structured questionnaire. Descriptive statistics, cluster analysis, and generalized additive models were used for in-depth analysis of the dataset. An examination of fertility patterns indicates that, on average, working women bear 2.90 live children, while their non-working counterparts have an average of 3.52 children. Stillbirth was reported in 13% of housewives and 15.1% of working women. However, further analysis revealed that the relationship between women's employment status and fertility behavior varied depending on Social and Cultural Norms, Reproductive Rights, Workplace Policies, Economic Independence, Age, and Life Stage. Our findings suggest that promoting access to family-friendly policies and services, as well as challenging gender norms and cultural values, could help address the impact of women's employment on fertility behavior.


Assuntos
Fertilidade , Classe Social , Criança , Feminino , Humanos , Fatores Socioeconômicos , Dinâmica Populacional , Paquistão , Demografia , Escolaridade
6.
PLoS One ; 19(3): e0300248, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38470882

RESUMO

In theory, the introduction of individuals infected with an incompatible strain of Wolbachia pipientis into a recipient host population should result in the symbiont invasion and reproductive failures caused by cytoplasmic incompatibility (CI). Modelling studies combining Wolbachia invasion and host population dynamics show that these two processes could interact to cause a transient population decline and, in some conditions, extinction. However, these effects could be sensitive to density dependence, with the Allee effect increasing the probability of extinction, and competition reducing the demographic impact of CI. We tested these predictions with laboratory experiments in the fruit fly Drosophila suzukii and the transinfected Wolbachia strain wTei. Surprisingly, the introduction of wTei into D. suzukii populations at carrying capacity did not result in the expected wTei invasion and transient population decline. In parallel, we found no Allee effect but strong negative density dependence. From these results, we propose that competition interacts in an antagonistic way with Wolbachia-induced cytoplasmic incompatibility on insect population dynamics. If future models and data support this hypothesis, pest management strategies using Wolbachia-induced CI should target populations with negligible competition but a potential Allee effect, for instance at the beginning of the reproductive season.


Assuntos
Drosophila , Wolbachia , Humanos , Animais , Citoplasma , Dinâmica Populacional , Insetos
7.
J Math Biol ; 88(3): 35, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427042

RESUMO

We study an integro-difference equation model that describes the spatial dynamics of a species with a strong Allee effect in a shifting habitat. We examine the case of a shifting semi-infinite bad habitat connected to a semi-infinite good habitat. In this case we rigorously establish species persistence (non-persistence) if the habitat shift speed is less (greater) than the asymptotic spreading speed of the species in the good habitat. We also examine the case of a finite shifting patch of hospitable habitat, and find that the habitat shift speed must be less than the asymptotic spreading speed associated with the habitat and there is a critical patch size for species persistence. Spreading speeds and traveling waves are established to address species persistence. Our numerical simulations demonstrate the theoretical results and show the dependence of the critical patch size on the shift speed.


Assuntos
Ecossistema , Modelos Biológicos , Simulação por Computador , Dinâmica Populacional
8.
Nat Commun ; 15(1): 2105, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453897

RESUMO

Photosynthesis fuels primary production at the base of marine food webs. Yet, in many surface ocean ecosystems, diel-driven primary production is tightly coupled to daily loss. This tight coupling raises the question: which top-down drivers predominate in maintaining persistently stable picocyanobacterial populations over longer time scales? Motivated by high-frequency surface water measurements taken in the North Pacific Subtropical Gyre (NPSG), we developed multitrophic models to investigate bottom-up and top-down mechanisms underlying the balanced control of Prochlorococcus populations. We find that incorporating photosynthetic growth with viral- and predator-induced mortality is sufficient to recapitulate daily oscillations of Prochlorococcus abundances with baseline community abundances. In doing so, we infer that grazers in this environment function as the predominant top-down factor despite high standing viral particle densities. The model-data fits also reveal the ecological relevance of light-dependent viral traits and non-canonical factors to cellular loss. Finally, we leverage sensitivity analyses to demonstrate how variation in life history traits across distinct oceanic contexts, including variation in viral adsorption and grazer clearance rates, can transform the quantitative and even qualitative importance of top-down controls in shaping Prochlorococcus population dynamics.


Assuntos
Ecossistema , Prochlorococcus , Oceanos e Mares , Cadeia Alimentar , Dinâmica Populacional , Água do Mar/microbiologia , Oceano Pacífico
9.
Am Nat ; 203(4): 473-489, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38489777

RESUMO

AbstractTransient dynamics have always intrigued ecologists, but current rapid environmental change (inducing transients even in previously undisturbed systems) has highlighted their importance more than ever. Here, I introduce a method for analyzing the sensitivity of transient ecological dynamics to parameter perturbations. The question the method answers is: how would the community dynamics have unfolded for some time horizon had the parameters been slightly different? I apply the method to three empirically parameterized models: competition between native forbs and exotic grasses in California, a host-parasitoid system, and an experimental chemostat predator-prey model. These applications showcase the ecological insights one can gain from models using transient sensitivity analysis. First, one can find parameters and their combinations whose perturbations disproportionately affect a system. Second, one can identify particular windows of time during which the predicted deviation from the unperturbed trajectories is especially large and utilize this information for management purposes. Third, there is an inverse relationship between transient and long-term sensitivities whenever the interacting populations are ecologically similar; paradoxically, the smaller the immediate response of the system, the more extreme its long-term response will be.


Assuntos
Modelos Teóricos , Poaceae , Animais , Dinâmica Populacional , Comportamento Predatório , Ecossistema , Modelos Biológicos
10.
Chaos ; 34(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38490186

RESUMO

In many environments, predators have significantly longer lives and meet several generations of prey, or the prey population reproduces rapidly. The slow-fast effect can best describe such predator-prey interactions. The slow-fast effect ε can be considered as the ratio between the predator's linear death rate and the prey's linear growth rate. This paper examines a slow-fast, discrete predator-prey interaction with prey refuge and herd behavior to reveal its complex dynamics. Our methodology employs the eigenvalues of the Jacobian matrix to examine the existence and local stability of fixed points in the model. Through the utilization of bifurcation theory and center manifold theory, it is demonstrated that the system undergoes period-doubling bifurcation and Neimark-Sacker bifurcation at the positive fixed point. The hybrid control method is utilized as a means of controlling the chaotic behavior that arises from these bifurcations. Moreover, numerical simulations are performed to demonstrate that they are consistent with analytical conclusions and to display the complexity of the model. At the interior fixed point, it is shown that the model undergoes a Neimark-Sacker bifurcation for larger values of the slow-fast effect parameter by using the slow-fast effect parameter ε as the bifurcation parameter. This is reasonable since a large ε implies an approximate equality in the predator's death rate and the prey's growth rate, automatically leading to the instability of the positive fixed point due to the slow-fast impact on the predator and the presence of prey refuge.


Assuntos
Modelos Biológicos , Comportamento Predatório , Animais , Dinâmica Populacional
11.
Sci Rep ; 14(1): 6327, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491152

RESUMO

Long-term demographic studies at biogeographic transition zones can elucidate how body size mediates disturbance responses. Focusing on subtropical reefs in eastern Australia, we examine trends in the size-structure of corals with contrasting life-histories and zoogeographies surrounding the 2016 coral bleaching event (2010-2019) to determine their resilience and recovery capacity. We document demographic shifts, with disproportionate declines in the number of small corals and long-term persistence of larger corals. The incidence of bleaching (Pocillopora, Turbinaria) and partial mortality (Acropora, Pocillopora) increased with coral size, and bleached corals had greater risk of partial mortality. While endemic Pocillopora experienced marked declines, decadal stability of Turbinaria despite bleaching, coupled with abundance increase and bleaching resistance in Acropora indicate remarkable resilience of these taxa in the subtropics. Declines in the number of small corals and variable associations with environmental drivers indicate bottlenecks to recovery mediated by inhibitory effects of thermal extremes for Pocillopora (heat stress) and Acropora (heat and cold stress), and stimulatory effects of chlorophyll-a for Turbinaria. Although our study reveals signs of resilience, it foreshadows the vulnerability of subtropical corals to changing disturbance regimes that include marine heatwaves. Disparity in population dynamics suggest that subtropical reefs are ecologically distinct from tropical coral reefs.


Assuntos
Antozoários , Animais , Antozoários/fisiologia , Recifes de Corais , Dinâmica Populacional , Clorofila A , Resposta ao Choque Térmico
12.
Phys Rev E ; 109(2-1): 024224, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38491580

RESUMO

In this article we contemplate the dynamics of an additional food-provided prey-predator system. We assume that the behavior of cooperative predators induces fear in prey, which radically affects the prey's birth and death rates. We observe that the structural instability imposed by strong cooperative hunting among predators goes away with higher intensities of fear levels affecting the prey's reproductive output and mortality. High levels of prey refuge are not conducive to the survival of predators. In such a situation, adequate supply of high-quality additional food is favorable regarding the persistence and stability of the system. Interestingly, the system potentially exhibits two stable configurations under identical ecological conditions by allowing different bifurcation scenarios, including saddle-node and backward bifurcations, and associated hysteresis effects with prey refuge along with additional food quantity and quality. In the stochastic environment, the system experiences critical transitions through bifurcation-induced tipping events with time-varying additional food for predators. Enhanced disturbance events promote noise-induced switching and tipping events. Finally, our investigation explores whether impending population crashes resulting from the variability of additional food quantity and quality can reliably be predicted using early warning signals in the context of redshifted noise. Overall, our results may provide insights for finding control strategies in the context of community ecology.


Assuntos
Cadeia Alimentar , Modelos Biológicos , Animais , Acidentes de Trânsito , Comportamento Predatório , Dinâmica Populacional
13.
Ecol Lett ; 27(3): e14406, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38491734

RESUMO

Rapid evolution in colonising populations can alter our ability to predict future range expansions. Recent theory suggests that the dynamics of replicate range expansions are less variable, and hence more predictable, with increased selection at the expanding range front. Here, we test whether selection from environmental gradients across space produces more consistent range expansion speeds, using the experimental evolution of replicate duckweed populations colonising landscapes with and without a temperature gradient. We found that the range expansion across a temperature gradient was slower on average, with range-front populations displaying higher population densities, and genetic signatures and trait changes consistent with directional selection. Despite this, we found that with a spatial gradient range expansion speed became more variable and less consistent among replicates over time. Our results therefore challenge current theory, highlighting that chance can still shape the genetic response to selection to influence our ability to predict range expansion speeds.


Assuntos
Evolução Biológica , Dinâmica Populacional , Temperatura , Densidade Demográfica , Fenótipo
14.
J Math Biol ; 88(4): 44, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38498209

RESUMO

We consider stochastic dynamics of a population which starts from a small colony on a habitat with large but limited carrying capacity. A common heuristics suggests that such population grows initially as a Galton-Watson branching process and then its size follows an almost deterministic path until reaching its maximum, sustainable by the habitat. In this paper we put forward an alternative and, in fact, more accurate approximation which suggests that the population size behaves as a special nonlinear transformation of the Galton-Watson process from the very beginning.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Densidade Demográfica , Processos Estocásticos , Dinâmica Populacional
15.
PLoS One ; 19(3): e0298238, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38498579

RESUMO

Leading with the principle of 'people-oriented urbanization,' the adaptation of rural migrants in urban China has attracted increasing concerns from policy-makers and scholars. Today, China has proceeded to a new stage of urbanization. Many rural migrants prefer moving to cities near their home villages rather than to large cities, reflecting the changes in migration patterns and expectations of rural migrants. Although migrant adaptation has been repeatedly investigated in academia, researchers tend to address the topic in one host setting, while migrant adaptation in diverse urban settings has rarely been compared. This paper seeks to fill this research gap via a survey conducted in two cities with different urban settings in Jiangsu. The rural migrant adaptation experiences in the two cities are systematically compared. Our statistical results show that economic structure and living costs, on the one hand, and local regulations and socio-cultural environments, on the other hand, determine rural migrant adaptation experiences in different urban settings. Despite abundant employment opportunities in more-developed cities, the high living costs, working pressure, and strict institutional schemes significantly hamper rural migrant adaptation. In less-developed cities, limited employment opportunities and conservative socio-cultural environments hinder rural migrants from adapting in host societies. Our findings suggest that the governments of different cities need to tailor strategies to assist rural migrants in adapting in urban communities.


Assuntos
Migrantes , Humanos , Demografia , Dinâmica Populacional , População Urbana , Cidades , Emigração e Imigração , População Rural , China , Países em Desenvolvimento
16.
Nat Commun ; 15(1): 2409, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499539

RESUMO

The immediate, direct effects of the COVID-19 pandemic on the United States population are substantial. Millions of people were affected by the pandemic: many died, others did not give birth, and still others could not migrate. Research that has examined these individual phenomena is important, but fragmented. The disruption of mortality, fertility, and migration jointly affected U.S. population counts and, consequently, future population structure. We use data from the United Nations World Population Prospects and the cohort component projection method to isolate the effect of the pandemic on U.S. population estimates until 2060. If the pandemic had not occurred, we project that the population of the U.S. would have 2.1 million (0.63%) more people in 2025, and 1.7 million (0.44%) more people in 2060. Pandemic-induced migration changes are projected to have a larger long-term effect on future population size than mortality, despite comparable short-term effects.


Assuntos
COVID-19 , Pandemias , Humanos , Estados Unidos/epidemiologia , COVID-19/epidemiologia , Dinâmica Populacional , Fertilidade , Densidade Demográfica
17.
PLoS Comput Biol ; 20(3): e1011899, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38442132

RESUMO

The coexistence of obligate mutualists is often precariously close to tipping points where small environmental changes can drive catastrophic shifts in species composition. For example, microbial ecosystems can collapse by the decline of a strain that provides an essential resource on which other strains cross-feed. Here, we show that tipping points, ecosystem collapse, bistability and hysteresis arise even with very weak (non-obligate) mutualism provided the population is spatially structured. Based on numeric solutions of a metacommunity model and mean-field analyses, we demonstrate that weak mutualism lowers the minimal dispersal rate necessary to avoid stochastic extinction, while species need to overcome a mean threshold density to survive in this low dispersal rate regime. Our results allow us to make numerous predictions for mutualistic metacommunities regarding tipping points, hysteresis effects, and recovery from external perturbations, and let us draw general conclusions for ecosystems even with random, not necessarily mutualistic, interactions and systems with density-dependent dispersal rather than direct mutualistic interactions.


Assuntos
Ecossistema , Simbiose , Dinâmica Populacional
18.
Science ; 383(6688): eadg8488, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38484074

RESUMO

The worldwide loss of species diversity brings urgency to understanding how diverse ecosystems maintain stability. Whereas early ecological ideas and classic observations suggested that stability increases with diversity, ecological theory makes the opposite prediction, leading to the long-standing "diversity-stability debate." Here, we show that this puzzle can be resolved if growth scales as a sublinear power law with biomass (exponent <1), exhibiting a form of population self-regulation analogous to models of individual ontogeny. We show that competitive interactions among populations with sublinear growth do not lead to exclusion, as occurs with logistic growth, but instead promote stability at higher diversity. Our model realigns theory with classic observations and predicts large-scale macroecological patterns. However, it makes an unsettling prediction: Biodiversity loss may accelerate the destabilization of ecosystems.


Assuntos
Biodiversidade , Ecossistema , Biomassa , Dinâmica Populacional
19.
Rev Esp Salud Publica ; 982024 Mar 20.
Artigo em Espanhol | MEDLINE | ID: mdl-38516896

RESUMO

In Spain, the advances in medicine and pharmacology, technology, etc., together with the low birth rates (a product of various social phenomena that occurred during the 20th century), cause an unprecedented population aging, a situation that extends to the rest of the countries. Europeans. This circumstance leads to an increase in the number of elderly people in a situation of dependency, entailing challenges such as the increase in chronic diseases and palliative stages, the management of informal care, the economic cost of formal care and unwanted loneliness (SND). , among other. Regarding this last challenge, and its consequences, it can be said that: it is a silent problem of a new order that affects more and more people in Spain, Europe and the world; It represents a source of suffering for those who suffer from it and a limitation of the right to participate in society; causes negative consequences for health and emotional well-being; It is associated with certain social and economic costs. Today it is estimated that in our country 13.4% of people suffer from SND, that those who suffer from it have been in this situation for approximately six years and that 22.9% experience this feeling of loneliness throughout the day. Likewise, in Europe as a whole, around thirty million people frequently feel lonely. Considering the sex variable, it is women who suffer from this problem with the highest prevalence (14.8% in the case of women and 12.1% in the case of men). Among the factors associated with this trend is life expectancy at birth. It should be said in this regard that, in recent decades, our country has experienced an increase in life expectancy by almost five years, being greater in the case of women. By 2022 this increase amounts to 83.08 years (women=85.7/men=80.3), a fact that places Spain in tenth place in the classification of the 194 countries that publish their life expectancy.


En España los avances de la medicina y la farmacología, la tecnología, etc., unidos a los bajos índices de natalidad (producto de diversos fenómenos sociales acaecidos durante el siglo XX), originan un envejecimiento poblacional sin precedentes, situación extendida al resto de países europeos. Tal circunstancia lleva aparejada un incremento de personas mayores en situación de dependencia, conllevando desafíos como pueden ser el aumento de las enfermedades crónicas y los estadios paliativos, la gestión del cuidado informal, el coste económico del cuidado formal y la soledad no deseada (SND), entre otras. Respecto de este último desafío, y sus consecuencias, se puede decir que: se trata de un problema silente de nuevo orden que afecta cada vez a más personas en España, Europa y el mundo; supone una fuente de sufrimiento para quien la padece y una limitación del derecho de participación en la sociedad; provoca consecuencias negativas para la salud y el bienestar emocional; lleva asociada ciertos costes sociales y económicos. Hoy día se estima que en nuestro país un 13,4% de las personas sufren SND, que quienes la padecen llevan aproximadamente seis años en dicha situación y que el 22,9% experimenta este sentimiento de soledad durante todo el día.


Assuntos
Solidão , Saúde Pública , Masculino , Recém-Nascido , Humanos , Feminino , Idoso , Espanha/epidemiologia , Expectativa de Vida , Dinâmica Populacional
20.
J Biol Dyn ; 18(1): 2332279, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38517146

RESUMO

We investigate the dynamics of a prey-predator model with cooperative hunting among specialist predators and maturation delay in predator growth. First, we consider a model without delay and explore the effect of hunting time on the coexistence of predator and their prey. When the hunting time is long enough and the cooperation rate among predators is weak, prey and predator species tend to coexist. Furthermore, we observe the occurrences of a series of bifurcations that depend on the cooperation rate and the hunting time. Second, we introduce a maturation delay for predator growth and analyse its impact on the system's dynamics. We find that as the delay becomes larger, predator species become more likely to go extinct, as the long maturation delay hinders the growth of the predator population. Our numerical exploration reveals that the delay causes shifts in both the bifurcation curves and bifurcation thresholds of the non-delayed system.


Assuntos
Cadeia Alimentar , Modelos Biológicos , Animais , Dinâmica Populacional , Caça , Comportamento Predatório , Ecossistema
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