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1.
Ecol Evol ; 13(1): e9704, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36687801

RESUMEN

Fecundity, the number of young produced by a breeding pair during a breeding season, is a primary component in evolutionary and ecological theory and applications. Fecundity can be influenced by many environmental factors and requires long-term study due to the range of variation in ecosystem dynamics. Fecundity data often include a large proportion of zeros when many pairs fail to produce any young during a breeding season due to nest failure or when all young die independently after fledging. We conducted color banding and monthly censuses of Florida scrub-jays (Aphelocoma coerulescens) across 31 years, 15 populations, and 761 territories along central Florida's Atlantic coast. We quantified how fecundity (juveniles/pair-year) was influenced by habitat quality, presence/absence of nonbreeders, population density, breeder experience, and rainfall, with a zero-inflated Bayesian hierarchical model including both a Bernoulli (e.g., brood success) and a Poisson (counts of young) submodel, and random effects for year, population, and territory. The results identified the importance of increasing "strong" quality habitat, which was a mid-successional state related to fire frequency and extent, because strong territories, and the proportion of strong territories in the overall population, influenced fecundity of breeding pairs. Populations subject to supplementary feeding also had greater fecundity. Territory size, population density, breeder experience, and rainfall surprisingly had no or small effects. Different mechanisms appeared to cause annual variation in fecundity, as estimates of random effects were not correlated between the success and count submodels. The increased fecundity for pairs with nonbreeders, compared to pairs without, identified empirical research needed to understand how the proportion of low-quality habitats influences population recovery and sustainability, because dispersal into low-quality habitats can drain nonbreeders from strong territories and decrease overall fecundity. We also describe how long-term study resulted in reversals in our understanding because of complications involving habitat quality, sociobiology, and population density.

2.
J Endod ; 41(9): 1437-40, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26027874

RESUMEN

INTRODUCTION: Cultural competencies in multicultural societies with different ethnic perceptions pose a challenge during the management and treatment of patients with dental fear and anxiety. This study aimed to identify the most common and relevant pathways of fear and anxiety related to root canal treatment in different ethnic groups. METHODS: All participants visiting the Griffith University Dental Clinics, Gold Coast, Australia, were invited to participate if they had undergone primary root canal treatment or were scheduled to undergo the same. Patients with mental disabilities, those with no history of root canal treatment, those who only had surgical root canal treatment, and those below 20 years old were excluded. All participants completed the "My Endodontic Fear questionnaire." RESULTS: Eight hundred seventy-nine patients (20-90 years old) who had root canal treatment or were scheduled to have one consented to participate in this study. White (54.5%) and Arab/African respondents (30.9%) were more likely (P < .001) to use the conditioning pathway compared with East Asian (10.5%) or Aboriginal/Pacific Islander groups (3.9%). Age was a significant factor for all ethnicities (P < .05); 40-year-old and 65+-year-old groups showed less fear compared with the 20- to 39-year old groups. Female sex was significantly related to the use of the informative (P < .001) and parental (P = .002) pathways. CONCLUSIONS: The present study showed that different pathways appear to be adopted by different ethnic groups, indicating the importance of customizing strategies in a multicultural society to manage fear and anxiety related to root canal treatment.


Asunto(s)
Ansiedad , Etnicidad/psicología , Miedo , Tratamiento del Conducto Radicular/psicología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Adulto Joven
3.
Br J Haematol ; 168(1): 26-37, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25145701

RESUMEN

Analysis of short tandem repeats (STR) is the predominant method for post-transplant monitoring of donor engraftment. It can enable early detection of disease relapse, level of engraftment and provide useful information on the graft-versus-host disease (GVHD)/graft-versus-tumour (GVT) effect, facilitating therapeutic intervention. Harmonization and standardization of techniques and result interpretation is essential to reduce the impact of laboratory variability on both clinical management and the results of multi-centre clinical trials. However, the United Kingdom National External Quality Assessment Service for Leucocyte Immunophenotyping (UK NEQAS LI) has highlighted significant issues inherent in STR testing that impact upon inter- and intra- laboratory variation. We present here consensus best practice guidelines and recommendations for STR chimerism testing, data interpretation and reporting that have been drawn up and agreed by a consortium of 11 UK and Eire clinical laboratories. This document uses data obtained from the UK NEQAS LI Post-Stem Cell Transplant (SCT) Chimerism Monitoring Programme.


Asunto(s)
Quimerismo , Trasplante de Células Madre Hematopoyéticas , Quimera por Trasplante , Pruebas Genéticas/métodos , Pruebas Genéticas/normas , Humanos , Repeticiones de Microsatélite , Quimera por Trasplante/genética , Trasplante Homólogo , Espera Vigilante
4.
Ecology ; 91(11): 3354-64, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21141196

RESUMEN

Many ecosystems are influenced by disturbances that create specific successional states and habitat structures that species need to persist. Estimating transition probabilities between habitat states and modeling the factors that influence such transitions have many applications for investigating and managing disturbance-prone ecosystems. We identify the correspondence between multistate capture-recapture models and Markov models of habitat dynamics. We exploit this correspondence by fitting and comparing competing models of different ecological covariates affecting habitat transition probabilities in Florida scrub and flatwoods, a habitat important to many unique plants and animals. We subdivided a large scrub and flatwoods ecosystem along central Florida's Atlantic coast into 10-ha grid cells, which approximated average territory size of the threatened Florida Scrub-Jay (Aphelocoma coerulescens), a management indicator species. We used 1.0-m resolution aerial imagery for 1994, 1999, and 2004 to classify grid cells into four habitat quality states that were directly related to Florida Scrub-Jay source-sink dynamics and management decision making. Results showed that static site features related to fire propagation (vegetation type, edges) and temporally varying disturbances (fires, mechanical cutting) best explained transition probabilities. Results indicated that much of the scrub and flatwoods ecosystem was resistant to moving from a degraded state to a desired state without mechanical cutting, an expensive restoration tool. We used habitat models parameterized with the estimated transition probabilities to investigate the consequences of alternative management scenarios on future habitat dynamics. We recommend this multistate modeling approach as being broadly applicable for studying ecosystem, land cover, or habitat dynamics. The approach provides maximum-likelihood estimates of transition parameters, including precision measures, and can be used to assess evidence among competing ecological models that describe system dynamics.


Asunto(s)
Ecosistema , Modelos Biológicos , Pájaros Cantores/fisiología , Animales , Florida , Plantas , Dinámica Poblacional
5.
Ecology ; 90(11): 3180-9, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19967873

RESUMEN

Quantifying habitat-specific survival and changes in habitat quality within disturbance-prone habitats is critical for understanding population dynamics and variation in fitness, and for managing degraded ecosystems. We used 18 years of color-banding data and multistate capture-recapture models to test whether habitat quality within territories influences survival and detection probability of breeding Florida Scrub-Jays (Aphelocoma coerulescens) and to estimate bird transition probabilities from one territory quality state to another. Our study sites were along central Florida's Atlantic coast and included two of the four largest metapopulations within the species range. We developed Markov models for habitat transitions and compared these to bird transition probabilities. Florida Scrub-Jay detection probabilities ranged from 0.88 in the tall territory state to 0.99 in the optimal state; detection probabilities were intermediate in the short state. Transition probabilities were similar for birds and habitat in grid cells mapped independently of birds. Thus, bird transitions resulted primarily from habitat transitions between states over time and not from bird movement. Survival ranged from 0.71 in the short state to 0.82 in the optimal state, with tall states being intermediate. We conclude that average Florida Scrub-Jay survival will remain at levels that lead to continued population declines because most current habitat quality is only marginally suitable across most of the species range. Improvements in habitat are likely to be slow and difficult because tall states are resistant to change and the optimal state represents an intermediate transitional stage. The multistate modeling approach to quantifying survival and habitat transition probabilities is useful for quantifying habitat transition probabilities and comparing them to bird transition probabilities to test for habitat selection in dynamic environments.


Asunto(s)
Ecosistema , Passeriformes/fisiología , Reproducción/fisiología , Animales , Femenino , Masculino , Modelos Biológicos , Análisis de Supervivencia
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