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1.
J Environ Manage ; 316: 115221, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35569353

RESUMEN

Agri-environment incentives form a central mechanism supporting changes to land management to provide public benefits. This study assesses the medium-term effects of woodland management on 13 target, specialist woodland bird species, as well as other woodland birds in a single region of the UK. The abundance of breeding birds (using two methods: point counts and territory mapping) and metrics of woodland structure were recorded on sites with Woodland Improvement Grants (improvement sites) and nearby comparison sites (control sites). Initial measurements were made prior to management and repeated 7-9 years later. A separate comparison of changes in bird abundance was made between the managed woodland sites and woodland from similar landscapes surveyed as part of the national Breeding Bird Survey (BBS). There was an increase in abundance of target species on improvement sites compared to a decrease on both control sites and BBS sites, although this was only evident from point count data. The effects on target species were stronger than for other woodland specialists and there was no apparent effect on woodland generalists, suggesting that the management interventions were appropriate for the target species. Changes in woodland structure were generally consistent with the expected effect of management, with lower tree density and greater Bramble (Rubus sp.) cover. However, contrary to the aim of increasing understorey cover, a reduction was recorded within the 2-10 m height category in improvement sites. This contrast is due to the removal of young trees during thinning affecting this height band and the short time period since management to allow regrowth. Our findings show that bespoke management supported through government agri-environment incentives can have a positive impact on target woodland birds. For managed forests, identifying species requirements and how management can be adapted to improve their habitats can be an effective way of delivering biodiversity gains when financial incentives are provided to achieve policy goals.


Asunto(s)
Conservación de los Recursos Naturales , Fitomejoramiento , Animales , Biodiversidad , Aves , Ecosistema , Bosques , Árboles
2.
Nat Commun ; 13(1): 2112, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35440555

RESUMEN

The phenology of many species shows strong sensitivity to climate change; however, with few large scale intra-specific studies it is unclear how such sensitivity varies over a species' range. We document large intra-specific variation in phenological sensitivity to temperature using laying date information from 67 populations of two co-familial European songbirds, the great tit (Parus major) and blue tit (Cyanistes caeruleus), covering a large part of their breeding range. Populations inhabiting deciduous habitats showed stronger phenological sensitivity than those in evergreen and mixed habitats. However, populations with higher sensitivity tended to have experienced less rapid change in climate over the past decades, such that populations with high phenological sensitivity will not necessarily exhibit the strongest phenological advancement. Our results show that to effectively assess the impact of climate change on phenology across a species' range it will be necessary to account for intra-specific variation in phenological sensitivity, climate change exposure, and the ecological characteristics of a population.


Asunto(s)
Passeriformes , Pájaros Cantores , Animales , Cambio Climático , Estaciones del Año , Temperatura
3.
PLoS One ; 11(5): e0155241, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27182711

RESUMEN

Large-scale climate processes influence many aspects of ecology including breeding phenology, reproductive success and survival across a wide range of taxa. Some effects are direct, for example, in temperate-zone birds, ambient temperature is an important cue enabling breeding effort to coincide with maximum food availability, and earlier breeding in response to warmer springs has been documented in many species. In other cases, time-lags of up to several years in ecological responses have been reported, with effects mediated through biotic mechanisms such as growth rates or abundance of food supplies. Here we use 23 years of data for a temperate woodland bird species, the great tit (Parus major), breeding in deciduous woodland in eastern England to demonstrate a time-lagged linear relationship between the on-set of egg laying and the winter index of the North Atlantic Oscillation such that timing can be predicted from the winter index for the previous year. Thus the timing of bird breeding (and, by inference, the timing of spring events in general) can be predicted one year in advance. We also show that the relationship with the winter index appears to arise through an abiotic time-lag with local spring warmth in our study area. Examining this link between local conditions and larger-scale processes in the longer-term showed that, in the past, significant relationships with the immediately preceding winter index were more common than those with the time-lagged index, and especially so from the late 1930s to the early 1970s. However, from the mid 1970s onwards, the time-lagged relationship has become the most significant, suggesting a recent change in climate patterns. The strength of the current time-lagged relationship suggests that it might have relevance for other temperature-dependent ecological relationships.


Asunto(s)
Aves , Cruzamiento , Clima , Reproducción , Animales , Cambio Climático , Inglaterra , Estaciones del Año , Temperatura , Factores de Tiempo
4.
Chest ; 126(6): 1897-904, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15596690

RESUMEN

STUDY OBJECTIVE: To use an existing database from a large cohort study with follow-up as long as 5.5 years to assess the extended prognosis of patients who survived their hospitalizations for severe acute respiratory failure (ARF). DESIGN, SETTING, AND PATIENTS: Secondary analysis of an inception cohort of 1,722 patients with ARF requiring mechanical ventilation from five major medical centers who were entered into the prospective Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatment. The 1,075 patients (62.4%) who survived hospitalization had systematic follow-up of vital status for a median time of 662 days (interquartile range, 327 to 1,049 days; range, 2 to 2,014 days). Interviews performed a median of 5 months after hospital discharge assessed functional capacity and quality of life (QOL). The main outcome measure was survival after hospital discharge. Secondary measures were functional status and QOL. Cox proportional hazard regression identified factors influencing posthospital survival. RESULTS: The median survival time after hospital discharge for ARF was > 5.3 years. The posthospital survival time was shorter for those with older age, male gender, several preexisting comorbid conditions, worse prehospital functional status, greater acute physiologic derangement, and a do-not-resuscitate order while in the hospital, and for those discharged to a location other than home. Five months after hospital discharge, 48% of survivors needed help with at least one activity of daily living, and 27% rated their QOL as poor or fair. However, most of these impairments were present before respiratory failure occurred. CONCLUSIONS: Extended survival is common among patients with ARF who require mechanical ventilation and who survive hospitalization. Among these patients, only a small fraction of the impairment in activity and QOL can be considered to be a sequela of the respiratory failure or its therapy. These findings are relevant to the care decisions for such critically ill patients.


Asunto(s)
Respiración Artificial , Insuficiencia Respiratoria/terapia , Actividades Cotidianas , Enfermedad Aguda , Anciano , Femenino , Estudios de Seguimiento , Costos de Hospital , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Pronóstico , Modelos de Riesgos Proporcionales , Calidad de Vida , Insuficiencia Respiratoria/economía , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/mortalidad , Tasa de Supervivencia
5.
J Gen Virol ; 84(Pt 10): 2807-2817, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-13679615

RESUMEN

The introduction and rapid dispersal of the African flavivirus West Nile virus (WNV) throughout North America, and the high fatality rate due to encephalitis in birds, horses, other wildlife species and humans, has attracted major attention worldwide. Usutu virus, another flavivirus, came to prominence in 2001, when it was identified as the agent responsible for a drop in the bird population in Austria; previously this encephalitic virus was found only in birds and mosquitoes in Africa. Sindbis virus, a pathogenic alphavirus that causes arthritis, is widespread throughout Africa, Europe, Asia and Australia, infecting a range of arthropods and vertebrates and is genetically related to encephalitic viruses in North America. Currently there is no evidence that any of these viruses cause disease in the UK. Here the presence of virus-specific neutralizing antibodies is reported in the sera of resident and migrant birds in the UK, implying that each of these viruses is being introduced to UK birds, possibly by mosquitoes. This is supported by nucleotide sequencing that identified three slightly different sequences of WNV RNA in tissues of magpies and a blackbird. The detection of specific neutralizing antibodies to WNV in birds provides a plausible explanation for the lack of evidence of a decrease in the bird population in the UK compared with North America. The potential health risk posed to humans and animals by these viruses circulating in the UK is discussed.


Asunto(s)
Anticuerpos Antivirales/sangre , Enfermedades de las Aves/virología , Virus de la Encefalitis Japonesa (Subgrupo)/inmunología , Virus Sindbis/inmunología , Virus del Nilo Occidental/inmunología , Infecciones por Alphavirus/inmunología , Infecciones por Alphavirus/veterinaria , Infecciones por Alphavirus/virología , Animales , Secuencia de Bases , Enfermedades de las Aves/inmunología , Aves/virología , Encefalitis por Arbovirus/inmunología , Encefalitis por Arbovirus/veterinaria , Encefalitis por Arbovirus/virología , Infecciones por Flavivirus/inmunología , Infecciones por Flavivirus/veterinaria , Infecciones por Flavivirus/virología , Datos de Secuencia Molecular , Pruebas de Neutralización , ARN Viral/análisis , Análisis de Secuencia de ADN , Reino Unido , Ensayo de Placa Viral , Virus del Nilo Occidental/clasificación , Virus del Nilo Occidental/genética
6.
Liver Transpl ; 8(10): 925-31, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12360435

RESUMEN

The hepatopulmonary syndrome (HPS), consisting of elevated alveolar-arterial oxygen gradient and intrapulmonary vascular abnormalities in the presence of advanced liver disease, is associated with high mortality. Liver transplantation (LT) has been used for the treatment of HPS; however, the success of LT for the treatment of HPS is not uniformly documented. We reviewed our experience over a 5-year period and identified eight adult patients with incapacitating respiratory symptoms compatible with HPS. Inclusion criteria included hypoxemia, normal lung volumes, reduced oxygen diffusing capacity (D(L)CO), and the presence of intrapulmonary shunting. Underlying liver disease was caused by hepatitis C (2 patients), primary biliary cirrhosis (1 patient), cryptogenic cirrhosis (1 patient), alcohol (2 patients), and hepatitis C with alcohol (2 patients). Six out of eight patients required preoperative oxygen support. Severe hypoxemia was present in seven patients (Pa(O2) 51.5 +/- 8.2 mm Hg). Three patients had complicating pulmonary hypertension. All patients exhibited a severely reduced D(L)CO (44.6 +/- 12.2% of predicted value). Six patients were transplanted, with five requiring oxygen support at the time of discharge. Resolution of oxygen dependency occurred in all patients but was delayed in the two patients exhibiting complicating pulmonary hypertension (288.5 +/- 37.4 v 53.5 +/- 35.7 days). All patients exhibited O2 saturations greater than 98% on room air. Currently, three patients are alive and off oxygen. The current report documents successful resolution of hypoxemia after LT in this pilot cohort. This supports the newly implemented United Network for Organ Sharing (UNOS) criteria, that LT for HPS may be extended to include patients with Pa(O2) < 60 mm Hg.


Asunto(s)
Síndrome Hepatopulmonar/fisiopatología , Síndrome Hepatopulmonar/cirugía , Trasplante de Hígado , Anciano , Estudios de Cohortes , Ecocardiografía , Femenino , Síndrome Hepatopulmonar/diagnóstico por imagen , Humanos , Trasplante de Hígado/efectos adversos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Capacidad de Difusión Pulmonar , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
7.
Oecologia ; 108(1): 64-71, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28307734

RESUMEN

This paper considers, for eight species of woodland bird, the factors that influenced both local extinctions and recolonisations in 145 woods over 3 years. In all species, probability of local extinction was inversely related to population size; most local extinctions occurred in woods containing one to three breeding pairs. However, considerable variation in extinction probabilities occurred between species and between years. In addition, the suitability of habitat within a wood (more extinctions in less suitable woods) was important for wren Troglodytes troglodytes, song thrush Turdus philomelos and blue tit Parus caeruleus; also, the structure of the surrounding landscape was important for blue tit, great tit Parus major, and chaffinch Fringilla coelebs (more extinctions in localities with less woodland). In only two species was the probability of recolonisation related to any of the measured variables. Wrens were more likely to recolonise larger woods, whereas song thrushes were more likely to recolonise woods with a high habitat suitability rating and those which are more isolated from other woodland.

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