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1.
Chemosphere ; 364: 143186, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39191347

RESUMEN

The tobacco cutworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) is an economically important agricultural polyphagous pest worldwide. It has shown high resistance to several insecticides, including cypermethrin, a synthetic pyrethroid that is used in large-scale commercial agricultural applications. The present study investigated the development of selection-induced resistance to cypermethrin and associated fitness costs in S. litura. After continuous exposure to cypermethrin for consecutive fifteen generations, the cypermethrin-selected population (CYP-Sel) of S. litura developed a 21.2-fold resistance. The CYP-Sel strain had a relative fitness of 0.16 when treated with LC50, prolonged larval duration, and development time. Meanwhile, the strain also showed shorter adult duration, lower fecundity, and hatchability compared with the Unsel-Lab population. CYP-Sel population showed a significant disadvantage in intrinsic rate of natural increase (rm), net reproductive rate (Ro), and finite rate of increase (λ) when compared to the Unsel-Lab population. This knowledge could help to design resistance management strategies against this particular pest, along with potential management strategies to overcome the development of resistance.


Asunto(s)
Resistencia a los Insecticidas , Insecticidas , Larva , Dinámica Poblacional , Piretrinas , Spodoptera , Animales , Piretrinas/toxicidad , Spodoptera/efectos de los fármacos , Spodoptera/fisiología , Spodoptera/crecimiento & desarrollo , Insecticidas/toxicidad , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Fertilidad/efectos de los fármacos , Aptitud Genética/efectos de los fármacos
2.
Zentralbl Chir ; 149(4): 384-390, 2024 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-39111303

RESUMEN

Trauma surgical care in Germany faces major challenges. The increasing number of cases due to demographic change, combined with reduced bed capacity, requires a rethink in many areas. In order to continue to ensure basic and standard care at a high level and across the board in the future, economic incentives must be created to maintain sufficient locations for trauma care. At the same time, there is a shortage of skilled workers that will worsen in the coming years if appropriate measures are not taken to counteract it. Structural changes will also be needed to improve cross-sector networking between outpatient and inpatient care. With the increase in outpatient care, future shortages of both bed capacity and staff shortages may be buffered.


Asunto(s)
Predicción , Programas Nacionales de Salud , Centros Traumatológicos , Alemania , Humanos , Programas Nacionales de Salud/tendencias , Centros Traumatológicos/organización & administración , Centros Traumatológicos/tendencias , Heridas y Lesiones/cirugía , Heridas y Lesiones/terapia , Necesidades y Demandas de Servicios de Salud/tendencias , Capacidad de Camas en Hospitales , Colaboración Intersectorial , Dinámica Poblacional , Comunicación Interdisciplinaria , Traumatología/tendencias , Traumatología/organización & administración
3.
J Glob Health ; 14: 04144, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39024622

RESUMEN

Background: As the global population ages, the burden of cancer is increasing. We aimed to assess the impact of population ageing on cancer-related disability-adjusted life years (DALYs). Methods: We used the decomposition method to estimate the impact of ageing, population growth, and epidemiological change on cancer-related DALYs from 1990 to 2019, stratified by 204 countries/territories and by their sociodemographic index (SDI). This approach separates the net effect of population ageing from population growth and change in age-specific DALY rates. Results: Cancer-related DALYs among individuals aged ≥65 years increased by 95.14% between 1990 (52.25 million) and 2019 (101.96 million). Population growth was the main contributor to cancer-related DALYs (92.38 million, attributed proportion: 60.91%), followed by population ageing (41.38 million, 27.28%). Cancer-related DALYs attributed to population ageing followed a bell-shaped pattern when stratified by SDI, meaning they peaked in middle-SDI countries. Cancer-related DALYs attributed to ageing increased in 171 and decreased in 33 countries/territories. The top three cancer types with the highest increase in the absolute number of cancer-related DALYs associated with ageing were tracheal, bronchus, and lung (8.72 million); stomach (5.06 million); and colorectal (4.28 million) cancers, while the attributed proportion of DALYs was the highest in prostate (44.75%), pancreatic (40.93%), and non-melanoma skin (38.03%) cancers. Conclusions: Population ageing contributed to global cancer-related DALYs, revealing a bell-shaped pattern when stratified by socioeconomic development, affecting middle-SDI countries the most. To respond to the growing ageing population and reduce cancer-related DALYs, it is necessary to allocate health care resources and prioritize interventions for older adults.


Asunto(s)
Años de Vida Ajustados por Discapacidad , Salud Global , Neoplasias , Humanos , Neoplasias/epidemiología , Anciano , Salud Global/estadística & datos numéricos , Envejecimiento , Masculino , Dinámica Poblacional , Femenino , Anciano de 80 o más Años
4.
Glob Chang Biol ; 30(7): e17413, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38982678

RESUMEN

Tasmanian eucalypt forests are among the most carbon-dense in the world, but projected climate change could destabilize this critical carbon sink. While the impact of abiotic factors on forest ecosystem carbon dynamics have received considerable attention, biotic factors such as the input of animal scat are less understood. Tasmanian devils (Sarcophilus harrisii)-an osteophageous scavenger that can ingest and solubilize nutrients locked in bone material-may subsidize plant and microbial productivity by concentrating bioavailable nutrients (e.g., nitrogen and phosphorus) in scat latrines. However, dramatic declines in devil population densities, driven by the spread of a transmissible cancer, may have underappreciated consequences for soil organic carbon (SOC) storage and forest productivity by altering nutrient cycling. Here, we fuse experimental data and modeling to quantify and predict future changes to forest productivity and SOC under various climate and scat-quality futures. We find that devil scat significantly increases concentrations of nitrogen, ammonium, phosphorus, and phosphate in the soil and shifts soil microbial communities toward those dominated by r-selected (e.g., fast-growing) phyla. Further, under expected increases in temperature and changes in precipitation, devil scat inputs are projected to increase above- and below-ground net primary productivity and microbial biomass carbon through 2100. In contrast, when devil scat is replaced by lower-quality scat (e.g., from non-osteophageous scavengers and herbivores), forest carbon pools are likely to increase more slowly, or in some cases, decline. Together, our results suggest often overlooked biotic factors will interact with climate change to drive current and future carbon pool dynamics in Tasmanian forests.


Asunto(s)
Cambio Climático , Bosques , Marsupiales , Suelo , Animales , Carbono/metabolismo , Carbono/análisis , Marsupiales/fisiología , Nitrógeno/metabolismo , Nitrógeno/análisis , Fósforo/análisis , Fósforo/metabolismo , Dinámica Poblacional , Suelo/química , Microbiología del Suelo , Tasmania
5.
Aquat Toxicol ; 273: 106984, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38901220

RESUMEN

Oil spills are reported to have conflicting impacts of either injury or resilience on zooplankton communities, and physiological plasticity is speculated to be the possible causative factor. But how? An explanation was sought by exposing the marine rotifer Brachionus plicatilis to a series of water-accommodated fractions (WAFs) of crude oil under controlled laboratory conditions, and population dynamics, which is the core issue for zooplankton facing external stress, were analyzed. The total hydrocarbon concentration of WAFs was quickly degraded from a concentration of 5.0 mg L-1 to half within 24 h and then remained stable. No acute lethality was observed; only motion inhibition was observed in the group treated with 10 %, 50 % and 100 % WAFs, which occurred simultaneously with inhibition of feeding and filtration. However, sublethal exposure to the WAFs concentration series presented stimulation impacts on reproduction and even the population of B. plicatilis. The negative correlation between motion and reproduction seemed to indicate that a shift in the distribution of individual energy toward reproduction rather than motion resulted in increased reproduction after exposure to WAFs. More evidence from transmission electron microscopy (TEM) revealed ultrastructural impairment in both the ovaries and cilia in each treated group, and imbalance in mitochondrial numbers was one of the distinct features of alteration. WAFs stress may alter the energy utilization and storage paradigm, as indicated by the significant elevation in glycogen and the significant decrease in lipid content after WAFs exposure. Further evidence from metabolomics analysis showed that WAFs stress increased the level of lipid metabolism and inhibited some of the pathways in glucose metabolism. Sublethal acute toxicity was observed only in the first 24 h with WAFs exposure, and an energy strategy consisting of changes in the utilization and storage paradigm and reallocation is responsible for the population resilience of B. plicatilis during oil spills.


Asunto(s)
Petróleo , Rotíferos , Contaminantes Químicos del Agua , Animales , Contaminantes Químicos del Agua/toxicidad , Petróleo/toxicidad , Rotíferos/efectos de los fármacos , Dinámica Poblacional , Reproducción/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Femenino , Contaminación por Petróleo
6.
Mar Environ Res ; 199: 106604, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38908113

RESUMEN

The edible chiton Chiton articulatus is a commercially important mollusk found in the rocky intertidal zones of the Mexican tropical Pacific. Despite the intense harvesting in Acapulco Bay, Mexico, knowledge of its growth patterns is limited, hindering the development of effective management strategies. This study investigated the growth dynamics of C. articulatus using a multi-model inference approach based on size structure data collected in four sampling periods covering four decades. Results revealed continuous recruitment throughout the year, contributing to population resilience. The species exhibited growth plasticity, highlighting its adaptive potential. We found complex temporal patterns influenced mainly by climatic events. The El Niño event sowed higher growth rates and lower asymptotic length, while La Niña events showed the opposite pattern. This research provides insights into the growth dynamics of C. articulatus, highlighting the need for holistic management strategies for this commercially important species in the face of environmental change.


Asunto(s)
Poliplacóforos , Dinámica Poblacional , Animales , México , Poliplacóforos/fisiología , Poliplacóforos/crecimiento & desarrollo
7.
Sci Total Environ ; 934: 172981, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38705301

RESUMEN

Decommissioning consequences of offshore oil and gas infrastructure removal on marine population dynamics, including connectivity, are not well understood. We modelled the connectivity and metapopulation dynamics of three fish and two benthic invertebrate species inhabiting the natural rocky reefs and offshore oil and gas infrastructure located in the Bass Strait, south-east Australia. Using a network approach, we found that platforms are not major sources, destinations, or stepping-stones for most species, yet act as modest sources for connectivity of Corynactis australis (jewel anemone). In contrast, sections of subsea pipelines appear to act as stepping-stones, source and destination habitats of varying strengths for all study species, except for Centrostephanus rodgersii (long-spined sea urchin). Natural reefs were the main stepping-stones, local source, and destination habitats for all study species. These reefs were largely responsible for the overall metapopulation growth of all study species (average of 96 % contribution across all species), with infrastructure acting as a minor contributor (<2 % average contribution). Full or partial decommissioning of platforms should have a very low or negligible impact on the overall metapopulation dynamics of the species explored, except C. australis, while full removal of pipelines could have a low impact on the metapopulation dynamics of benthic invertebrate species and a moderate impact on fish species (up to 34.1 % reduction in the metapopulation growth). We recommend that the decision to remove offshore infrastructure, either in full or in-part, be made on a platform-by-platform basis and consider contributions of pipelines to connectivity and metapopulation dynamics.


Asunto(s)
Dinámica Poblacional , Animales , Industria del Petróleo y Gas , Yacimiento de Petróleo y Gas , Monitoreo del Ambiente , Arrecifes de Coral , Peces , Australia , Invertebrados/fisiología , Ecosistema , Organismos Acuáticos
8.
BMC Public Health ; 24(1): 1196, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38685025

RESUMEN

BACKGROUND: Residential mobility is believed to influence the occurrence and development of cancer; however, the results are inconclusive. Furthermore, limited studies have been conducted on Asian populations. This study aimed to evaluate the relationship between residential mobility and liver cancer risk among Chinese women. METHODS: We enrolled 72,818 women from urban Shanghai between 1996 and 2000, and then followed them until the end of 2016. Cox regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) to assess the association between residential mobility and liver cancer risk. A linear trend test was conducted by ranking variables. A sensitivity analysis was also conducted, excluding participants with follow-up times of less than 2 years, to prevent potential bias. RESULTS: During the 1,269,765 person-years of follow-up, liver cancer was newly diagnosed in 259 patients. Domestic migration (HR = 1.47, 95% CI, 1.44-1.50), especially immigration to Shanghai (HR = 1.47, 95% CI, 1.44-1.50) was associated with an increased risk of liver cancer. In addition, migration frequency, age at initial migration and first immigration to Shanghai had linear trends with an increased liver cancer risk (Ptrend <0.001). The results were similar when excluding participants with less than two years of follow-up. CONCLUSIONS: The possible association between residential mobility and a higher risk of liver cancer in women could suggest the need for effective interventions to reduce adverse environmental exposures and enhance people's health.


Asunto(s)
Neoplasias Hepáticas , Humanos , Femenino , China/epidemiología , Estudios Prospectivos , Persona de Mediana Edad , Neoplasias Hepáticas/epidemiología , Adulto , Dinámica Poblacional , Factores de Riesgo , Anciano , Modelos de Riesgos Proporcionales , Pueblos del Este de Asia
9.
RECIIS (Online) ; 18(1)jan.-mar. 2024.
Artículo en Portugués | LILACS, Coleciona SUS | ID: biblio-1553215

RESUMEN

Neste artigo, iremos apresentar como ocorreu a edição virtual da Maratona do Rio de Janeiro em 2020, ainda sem autorizações sanitárias para a realização de grandes eventos. Para isso, analisaremos o Guia do corredor, apresentado aos corredores na época. A competição é realizada por meio de uso de aplicativos, mas o atleta é estimulado a correr com o slogan "Não correr nunca foi uma opção". Abordamos os conceitos de necrodemografia e necropolítica. Entende-se que a Maratona do Rio pratica uma espécie de necropolíti-ca ao organizar a competição em pleno período pandêmico do Brasil, apesar de valorizar a paisagem da rua em suas plataformas comunicacionais.


In this article, we will present how the virtual edition of the Rio de Janeiro Marathon took place in 2020 in the middle of the pandemic, still without health permits to hold major events. For this, we will analyze the Runner's Guide presented to the runners at the time. The competition is carried out using applications, but the athlete is encouraged to run with the slogan "Not running was never an option". We approach the concepts of necrodemography and necropolitics. It is understood that the Rio Marathon practices a kind of necropolitics when organizing the competition in the middle of the pandemic period in Brazil, despite valuing the street landscape in its communication platforms.


Dans cet article, nous allons vous présenter comment s'est déroulée l'édition virtuelle du Marathon de Rio de Janeiro en 2020, toujours sans autorisations sanitaires pour les grands événements. Pour cela, nous analyserons le Guide du marathonien, présenté aux marathoniens à l'époque. La compétition se déroule à l'aide d'applications, mais l'athlète est encouragé à courir avec le slogan "Ne pas courir n'a jamais été une option". Nous abordons les concepts de nécrodémographie et de nécropolitique. Il est entendu que le Marathon de Rio pratique une sorte de nécropolitique en organisant la compétition en pleine pandémie au Brésil, malgré la valorisation du paysage de rue dans ses plateformes de communication.


Asunto(s)
Humanos , Carrera , Política , Factores Socioeconómicos , Dinámica Poblacional , Cuarentena , Demografía , COVID-19
10.
Rev. biol. trop ; Rev. biol. trop;72(supl.1): e58623, Mar. 2024. tab, graf
Artículo en Inglés | LILACS, SaludCR | ID: biblio-1559338

RESUMEN

Abstract Introduction: The sea cucumber Holothuria (Halodeima) grisea Selenka, 1867 is a common echinoderm in intertidal regions along the Brazilian coast, which recently became the focus of unreported and unregulated fisheries. This study was carried out in sandy-rocky substrates at Armação do Itapocoroy, Penha, Santa Catarina (26o47' S; 48o36' W), near its southern limit of geographic distribution. Objective: To determine the densities (individuals*m-2) of Holothuria (H.) grisea within a spatial-temporal perspective as well as to determine biometric and growth characteristics of the population. Methods: Two-meter wide transects perpendicular to the coastline were carried out in winter and spring 2019 and in summer and spring 2020, in periods of spring low-tides. In each sampling occasion the total number of specimens of H. grisea were determined, and a group of 90 organisms was submitted to in situ biometrics (weight, length and width), and immediately returned alive to their habitat. Results: The densities of H. (H.) grisea were significantly higher in the subtidal sector and lower in the upper intertidal sector with no indication of significant differences among sampling campaigns. Depth was the primary factor explaining the observed density patterns and rugosity of the substrate was secondary but also important. The body length ranged from 5.2 to 22.5 cm, whereas the weight varied from 6.0 to 230 g. The mean and modal lengths were 12.54 and 13 cm, respectively. Approximately 75 % of the population sampled was between 10 and 14 cm and the average weight was 60 g. Estimates from von Bertalanffy growth function indicate that the youngest sea cucumber was one year-old, and the oldest had approximately two and a half years. Conclusions: This is the first study to determine biometric parameters for H. (H.) grisea in southern Brazil and the first one to estimate growth and age estimates for a wild population of this species. The densities recorded in the present study were lower than those previously reported for this region, suggesting anthropic influence.


Resumen Introducción: El pepino de mar Holothuria (Halodeima) grisea Selenka, 1867 es un equinodermo común en las regiones intermareales a lo largo de la costa brasileña, que recientemente se convirtió en foco de pesquerías no declaradas y no reguladas. Este estudio se realizó en sustratos arenosos-rocosos en Armação do Itapocoroy, Penha, Santa Catarina (26o47' S; 48o36' W), cerca del límite sur de su distribución geográfica. Objetivo: Determinar las densidades (individuos*m-2) de Holothuria (H.) grisea dentro de una perspectiva espacio-temporal así como determinar las características biométricas y de crecimiento de la población. Métodos: Se realizaron transectos de dos metros de ancho perpendiculares a la línea de costa en invierno y primavera de 2019 y en verano y primavera de 2020, en periodos de bajamar sicigia. En cada ocasión de muestreo se determinó el número total de especímenes de H. (H.) grisea, y se sometió un grupo de 90 organismos a biometría in situ (peso, longitud y ancho), e inmediatamente se los devolvieron vivos a su hábitat. Resultados: Las densidades de H. (H.) grisea fueron significativamente más altas en el sector submareal y más bajas en el sector intermareal superior sin indicios de diferencias significativas entre las campañas de muestreo. La profundidad fue el factor principal que explica los patrones de densidad observados y la rugosidad del sustrato fue secundaria pero también importante. La longitud del cuerpo varió de 5.2 a 22.5 cm, mientras que el peso varió de 6.0 a 230 g. Las longitudes media y modal fueron 12.54 y 13 cm, respectivamente. Aproximadamente el 75 % de la población muestreada midió entre 10 y 14 cm y el peso promedio fue de 60 g. Estimados de la función de crecimiento de von Bertalanffy indican que el ejemplar más joven presentaba un año de edad, mientras el más viejo presentaba cerca de dos años y medio. Conclusiones: Este es el primer estudio que determina parámetros biométricos para una población de H. (H.) grisea en el sur de Brasil y el primero en estimar el crecimiento y edades para una población salvaje de esta especie. Las densidades registradas en el presente estudio fueron inferiores a las reportadas previamente para esta región sugiriendo la ocurrencia de influencia antrópica.


Asunto(s)
Animales , Dinámica Poblacional , Holothuria/crecimiento & desarrollo , Muestreo
11.
J Environ Manage ; 354: 120394, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38412729

RESUMEN

Algal blooms, exacerbated by climate change and eutrophication, have emerged as a global concern. In this study, we introduce a novel interpretable machine learning (ML) workflow tailored for investigating the dynamics of algal populations in grass-type lakes, Liangzi lake. Utilizing seven ML methods and incorporating the covariance matrix adaptation evolution strategy (CMA-ES), we predict algal density across three distinct time periods, resulting in the construction of a total of 30 ML models. The CMA-ES-CatBoost model consistently demonstrates superior predictive accuracy and generalization capability across these periods. Through the collective validation of various interpretable tools, we identify water temperature and permanganate index as the two most critical water quality parameters (WQIs) influencing algal density in Liangzi Lake. Additionally, we quantify the independent and interactive effects of WQIs on algal density, pinpointing key thresholds and trends. Furthermore, we determine the minimum combination of WQIs that achieves near-optimal predictive performance, striking a balance between accuracy and cost-effectiveness. These findings offer a scientific and economically efficient foundation for governmental agencies to formulate strategies for water quality management and sustainable development.


Asunto(s)
Lagos , Poaceae , Calidad del Agua , Eutrofización , Aprendizaje Automático , Dinámica Poblacional , Monitoreo del Ambiente , China
12.
Ecol Lett ; 27(2): e14370, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38348631

RESUMEN

Species coexistence in ecological communities is a central feature of biodiversity. Different concepts, i.e., contemporary niche theory, modern coexistence theory, and the unified neutral theory, have identified many building blocks of such ecological assemblies. However, other factors, such as phenotypic plasticity and stochastic inter-individual variation, have received little attention, in particular in animals. For example, how resource polyphenisms resulting in predator-prey interactions affect coexistence is currently unknown. Here, we present an integrative theoretical-experimental framework using the nematode plasticity model Pristionchus pacificus with its well-studied mouth-form dimorphism resulting in cannibalism. We develop an individual-based model that relies upon synthetic data based on our empirical measurements of fecundity and polyphenism to preserve demographic heterogeneity. We demonstrate how the interplay between plasticity and individual stochasticity result in all-or-nothing outcomes at the local level. Coexistence is made possible when spatial structure is introduced.


Asunto(s)
Nematodos , Conducta Predatoria , Animales , Fertilidad , Biota , Dinámica Poblacional
13.
Am J Bot ; 111(2): e16275, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38303667

RESUMEN

PREMISE: Snow is an important environmental factor affecting plant distribution. Past changes in snowfall regimes may have controlled the demographies of snow-dependent plants. However, our knowledge of changes in the distribution and demographies of such plants is limited because of the lack of fossil records. METHODS: Population genetic and landscape genetic analyses were used to investigate the response of population dynamics of Arnica mallotopus (Asteraceae)-a plant confined to heavy-snow areas of Japan-to changes in snowfall regimes from the Last Glacial Period to the Holocene. RESULTS: The population genetic analysis suggested that the four geographic lineages diverged during the Last Glacial Period. The interaction between reduced snowfall and lower temperatures during this period likely triggered population isolation in separate refugia. Subpopulation differentiation in the northern group was lower than in the southern group. Our ecological niche model predicted that the current distribution was patchy in the southern region; that is, the populations were isolated by topologically flat and climatically unsuitable lowlands. The landscape genetic analysis suggested that areas with little snowfall acted as barriers to the Holocene expansion of species distribution and continued limiting gene flow between local populations. CONCLUSIONS: These findings indicate that postglacial population responses vary among regions and are controlled by environmental and geographic factors. Thus, changes in snowfall regime played a major role in shaping the distribution and genetic structure of the snow-dependent plant.


Asunto(s)
Arnica , Variación Genética , Japón , Nieve , Dinámica Poblacional
14.
J Insect Sci ; 24(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38195070

RESUMEN

Termite nest repairs are considered a defensive conduct as they reduce the colony's exposure to the external environment. Repair activities are carried out by worker castes that can be polymorphic, representing a relationship between polymorphism and divisions of functions that can enhance task completion. Repairs are influenced by the extent of damage, nest volume, and the population dynamics of the building species, which regulate the recruitment of individuals for this activity. Our objective was to verify the performances (recruitment for repair) of dimorphic workers of Constrictotermes cyphergaster (Silvestri, 1901) during the damage repair activities performed on the external walls of termite nests of different sizes. We found a significant difference in the presence of dimorphic workers that performed repairs, with greater recruitment of the small morphotype, and observed an alternation of morphotypes between initial and final repair activities, with no influence of morphotype on the replacement pattern. Our results also showed that the total number of recruited workers decreased with increasing nest volume. These results help to better understand the social organization of a Nasutitermitinae termite species and the strategies adopted to protect its colonies.


Asunto(s)
Cucarachas , Isópteros , Humanos , Animales , Polimorfismo Genético , Dinámica Poblacional
15.
Nat Ecol Evol ; 8(2): 293-303, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38191839

RESUMEN

Top predator declines are pervasive and often have dramatic effects on ecological communities via changes in food web dynamics, but their evolutionary consequences are virtually unknown. Tasmania's top terrestrial predator, the Tasmanian devil, is declining due to a lethal transmissible cancer. Spotted-tailed quolls benefit via mesopredator release, and they alter their behaviour and resource use concomitant with devil declines and increased disease duration. Here, using a landscape community genomics framework to identify environmental drivers of population genomic structure and signatures of selection, we show that these biotic factors are consistently among the top variables explaining genomic structure of the quoll. Landscape resistance negatively correlates with devil density, suggesting that devil declines will increase quoll genetic subdivision over time, despite no change in quoll densities detected by camera trap studies. Devil density also contributes to signatures of selection in the quoll genome, including genes associated with muscle development and locomotion. Our results provide some of the first evidence of the evolutionary impacts of competition between a top predator and a mesopredator species in the context of a trophic cascade. As top predator declines are increasing globally, our framework can serve as a model for future studies of evolutionary impacts of altered ecological interactions.


Asunto(s)
Marsupiales , Animales , Marsupiales/genética , Metagenómica , Dinámica Poblacional , Cadena Alimentaria
16.
Elife ; 132024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38288729

RESUMEN

Ancient DNA research in the past decade has revealed that European population structure changed dramatically in the prehistoric period (14,000-3000 years before present, YBP), reflecting the widespread introduction of Neolithic farmer and Bronze Age Steppe ancestries. However, little is known about how population structure changed from the historical period onward (3000 YBP - present). To address this, we collected whole genomes from 204 individuals from Europe and the Mediterranean, many of which are the first historical period genomes from their region (e.g. Armenia and France). We found that most regions show remarkable inter-individual heterogeneity. At least 7% of historical individuals carry ancestry uncommon in the region where they were sampled, some indicating cross-Mediterranean contacts. Despite this high level of mobility, overall population structure across western Eurasia is relatively stable through the historical period up to the present, mirroring geography. We show that, under standard population genetics models with local panmixia, the observed level of dispersal would lead to a collapse of population structure. Persistent population structure thus suggests a lower effective migration rate than indicated by the observed dispersal. We hypothesize that this phenomenon can be explained by extensive transient dispersal arising from drastically improved transportation networks and the Roman Empire's mobilization of people for trade, labor, and military. This work highlights the utility of ancient DNA in elucidating finer scale human population dynamics in recent history.


Asunto(s)
ADN Antiguo , Genoma Humano , Humanos , Europa (Continente) , Francia , Genética de Población , Dinámica Poblacional , Migración Humana
17.
J Math Biol ; 88(2): 18, 2024 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-38245595

RESUMEN

When examining some factors that contribute to the growth or decline of a population or tumor, it is essential to consider a random hypothesis. By analyzing the effects of stress on a population (or volume of tumor growth) in a random environment, we develop stochastic models describing the dynamics of the population (or tumor growth) based on random adjustments to the population's intrinsic growth rate, carrying capacity, and harvesting efforts (or tumor treatments). Apart from the models' ability to capture fluctuations, the availability of a shape parameter in the models gives it the flexibility to describe a variety of population/tumor data with different shapes. The distribution of the stressed population size with or without harvesting (or treatments) is derived and used to calculate the maximum expected amount of harvests that can be taken from the population without depleting resources in the long run (or the minimum amount of chemotherapy needed to cause shrinkage or eradication of a tumor). The work done is applied to analyze tumor growth using published data comprising of the volume of breast tumor obtained by orthotopically implanting LM2-[Formula: see text] cells into the right inguinal mammary fat pads of 6- to 8-week-old female Severe Combined Immuno-Deficient mice.


Asunto(s)
Modelos Biológicos , Neoplasias , Animales , Femenino , Ratones , Dinámica Poblacional , Conservación de los Recursos Naturales , Densidad de Población , Crecimiento Demográfico
18.
Rev. cuba. med. mil ; 52(4)dic. 2023. tab
Artículo en Español | LILACS, CUMED | ID: biblio-1559852

RESUMEN

Introducción: Uno de los logros más importantes de la ciencia del siglo XX ha sido el avance en la medición de la riqueza comparativa de los países mediante indicadores, se destacan el producto interno bruto y el índice de desarrollo humano. Objetivo: Evaluar la validez del índice demográfico integral en la medición del nivel de desarrollo y estado de salud de una población para establecer un orden jerárquico acorde a estas 2 características. Método: Se realizó un estudio ecológico, se escogió como población a los 191 países que en el año 2019 disponían de información para el cálculo del índice de desarrollo humano; la muestra fue seleccionada por un muestreo simple aleatorio. La información se obtuvo de la página web Datosmacro. Para analizar los datos se emplearon los coeficientes de validez de Hernández- Nieto y V de Aiken, análisis factorial, correlación de Spearman y el coeficiente de Kappa. Resultados: El análisis por ítems reflejó un elevado acuerdo entre los jueces. Existió una alta correlación y elevada concordancia entre el índice demográfico integral y el índice de desarrollo humano. Se identificó una perfecta correlación entre los indicadores evaluados y el grado de desarrollo, con correlaciones iguales a 1 y -1. Conclusión: El índice demográfico integral constituye un indicador válido en la evaluación del envejecimiento, estado de salud y grado de desarrollo entre países, lo que permitió el ordenamiento de las poblaciones acorde a su desarrollo y condición de salud(AU)


Introduction: One of the most important achievements of science in the 20th century has been the progress in measuring the comparative wealth of countries through indicators, highlighting the gross domestic product and the human development index. Objective: To evaluate the validity of the comprehensive demographic index in measuring the level of development and health status of a population to establish a hierarchical order according to these two characteristics. Method: An ecological study was carried out, the 191 countries that in 2019 had information for the calculation of the human development index were chosen as the population; The sample was selected by simple random sampling. The information was obtained from the Datamacro website. To analyse the data, the Hernández-Nieto and Aiken V validity coefficients, factor analysis, Spearman correlation and the Kappa coefficient were used. Results: The analysis by items reflected a high agreement between the judges. There was a high correlation and high agreement between the comprehensive demographic index and the human development index. A perfect correlation was identified between the evaluated indicators and the degree of development, with correlations equal to 1 and -1. Conclusion: The comprehensive demographic index constitutes a valid indicator in the evaluation of aging, health status and degree of development between countries, which allowed the ordering of populations according to their development and health condition(AU)


Asunto(s)
Humanos , Factores Socioeconómicos , Estado de Salud , Reproducibilidad de los Resultados , Evaluación de Procesos, Atención de Salud/métodos , Indicadores Demográficos , Dinámica Poblacional , Estudios Ecológicos
20.
JCI Insight ; 8(24)2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-37934604

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a chronic parenchymal lung disease characterized by repetitive alveolar cell injury, myofibroblast proliferation, and excessive extracellular matrix deposition for which unmet need persists for effective therapeutics. The bioactive eicosanoid, prostaglandin F2α, and its cognate receptor FPr (Ptgfr) are implicated as a TGF-ß1-independent signaling hub for IPF. To assess this, we leveraged our published murine PF model (IER-SftpcI73T) expressing a disease-associated missense mutation in the surfactant protein C (Sftpc) gene. Tamoxifen-treated IER-SftpcI73T mice developed an early multiphasic alveolitis and transition to spontaneous fibrotic remodeling by 28 days. IER-SftpcI73T mice crossed to a Ptgfr-null (FPr-/-) line showed attenuated weight loss and gene dosage-dependent rescue of mortality compared with FPr+/+ cohorts. IER-SftpcI73T/FPr-/- mice also showed reductions in multiple fibrotic endpoints for which administration of nintedanib was not additive. Single-cell RNA-Seq, pseudotime analysis, and in vitro assays demonstrated Ptgfr expression predominantly within adventitial fibroblasts, which were reprogrammed to an "inflammatory/transitional" cell state in a PGF2α /FPr-dependent manner. Collectively, the findings provide evidence for a role for PGF2α signaling in IPF, mechanistically identify a susceptible fibroblast subpopulation, and establish a benchmark effect size for disruption of this pathway in mitigating fibrotic lung remodeling.


Asunto(s)
Dinoprost , Fibrosis Pulmonar Idiopática , Ratones , Animales , Dinoprost/metabolismo , Fibroblastos/metabolismo , Fibrosis Pulmonar Idiopática/patología , Fibrosis , Dinámica Poblacional
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