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1.
Glob Chang Biol ; 30(5): e17294, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38738554

RESUMEN

The potential for climate change to disrupt phenology-mediated interactions in interaction networks has attracted considerable attention in recent decades. Frequently, studies emphasize the fragility of ephemeral seasonal interactions, and the risks posed by phenological asynchrony. Here, we argue that the fitness consequences of asynchrony in phenological interactions may often be more buffered than is typically acknowledged. We identify three main forms that buffering may take: (i) mechanisms that reduce asynchrony between consumer and resource; (ii) mechanisms that reduce the costs of being asynchronous; and (iii) mechanisms that dampen interannual variance in performance across higher organizational units. Using synchrony between the hatching of winter moth caterpillars and the leafing of their host-plants as a case study, we identify a wide variety of buffers that reduce the detrimental consequences of phenological asynchrony on caterpillar individuals, populations, and meta-populations. We follow this by drawing on examples across a breadth of taxa, and demonstrate that these buffering mechanisms may be quite general. We conclude by identifying key gaps in our knowledge of the fitness and demographic consequences of buffering, in the context of phenological mismatch. Buffering has the potential to substantially alter our understanding of the biotic impacts of future climate change-a greater recognition of the contribution of these mechanisms may reveal that many trophic interactions are surprisingly resilient, and also serve to shift research emphasis to those systems with fewer buffers and towards identifying the limits of those buffers.


Asunto(s)
Cambio Climático , Mariposas Nocturnas , Animales , Larva/fisiología , Larva/crecimiento & desarrollo , Mariposas Nocturnas/fisiología , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/fisiología , Estaciones del Año
3.
Front Physiol ; 12: 682233, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34630133

RESUMEN

A variety of health benefits associated with physical activity depends upon the frequency, intensity, duration, and type of exercise. Intensity of exercise is the most elusive of these elements and yet has important implications for the health benefits and particularly cardiovascular outcomes elicited by regular physical activity. Authorities recommend that we obtain 150min of moderate to vigorous intensity physical activity (MVPA) each week. The current descriptions of moderate to vigorous intensity are not sufficient, and we wish to enhance understanding of MVPA by recognition of important boundaries that define these intensities. There are two key thresholds identified in incremental tests: ventilatory and lactate thresholds 1 and 2, which reflect boundaries related to individualized disturbance to homeostasis that are appropriate for prescribing exercise. VT2 and LT2 correspond with critical power/speed and respiratory compensation point. Moderate intensity physical activity approaches VT1 and LT1 and vigorous intensity physical activity is between the two thresholds (1 and 2). The common practice of prescribing exercise at a fixed metabolic rate (# of METs) or percentage of maximal heart rate or of maximal oxygen uptake (V̇O2max) does not acknowledge the individual variability of these metabolic boundaries. As training adaptations occur, these boundaries will change in absolute and relative terms. Reassessment is necessary to maintain regular exercise in the moderate to vigorous intensity domains. Future research should consider using these metabolic boundaries for exercise prescription, so we will gain a better understanding of the specific physical activity induced health benefits.

4.
Wellcome Open Res ; 6: 296, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36866280

RESUMEN

We present a genome assembly from an individual female Maniola jurtina (the meadow brown; Arthropoda; Insecta; Lepidoptera; Nymphalidae). The genome sequence is 402 megabases in span. The complete assembly is scaffolded into 30 chromosomal pseudomolecules, with the W and Z sex chromosome assembled. Gene annotation of this assembly on Ensembl has identified 12,502 protein coding genes.

5.
Nat Ecol Evol ; 5(2): 155-164, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33318690

RESUMEN

Climate warming has caused the seasonal timing of many components of ecological food chains to advance. In the context of trophic interactions, the match-mismatch hypothesis postulates that differential shifts can lead to phenological asynchrony with negative impacts for consumers. However, at present there has been no consistent analysis of the links between temperature change, phenological asynchrony and individual-to-population-level impacts across taxa, trophic levels and biomes at a global scale. Here, we propose five criteria that all need to be met to demonstrate that temperature-mediated trophic asynchrony poses a growing risk to consumers. We conduct a literature review of 109 papers studying 129 taxa, and find that all five criteria are assessed for only two taxa, with the majority of taxa only having one or two criteria assessed. Crucially, nearly every study was conducted in Europe or North America, and most studies were on terrestrial secondary consumers. We thus lack a robust evidence base from which to draw general conclusions about the risk that climate-mediated trophic asynchrony may pose to populations worldwide.


Asunto(s)
Cambio Climático , Europa (Continente) , América del Norte , Estaciones del Año , Temperatura
6.
Arch Orthop Trauma Surg ; 140(11): 1619-1631, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31974694

RESUMEN

INTRODUCTION: In adults, treatment of recalcitrant long bone non-union is extremely challenging, with poorly vascularised and atrophic defects unresponsive to standard non-vascularised bone graft treatment. Recent studies have documented the use of free vascularised periosteal flaps to achieve union in refractory long bone fracture non-union, yet its use is not well established. This systematic review aims to assess the evidence for free vascularised periosteal flaps in recalcitrant long bone non-union. MATERIALS AND METHODS: The MEDLINE®/PubMed® and Embase databases were searched for the Medical Subject Heading (MeSH) terms periosteal flap/vascularised flap/long bone/non-union/non united fracture in accordance with the PRISMA guidelines. Bibliographies were scrutinised for additional articles. RESULTS: Pooled data from 14 studies met the inclusions criteria, comprising 137 cases of non-union, with 117 relating to long bone non-union. Pooled data indicated an overall 99% (116/117) successful union rate. All studies were of mid- to low-level evidence (Level III, IV and V). Only one study directly compared vascularised periosteal flaps to non-vascularised bone grafts, showing union rates of 100% versus 80% and faster time to union (2 versus 5.5 months). CONCLUSIONS: Free vascularised periosteal flaps are promising with pooled data showing a 99% success rate in achieving union in refractory long bone non-union. This compares favourably with standard orthopaedic care consisting of revision fixation and non-vascularised bone graft union rates of approximately 80%. However, study design flaws should be addressed by validated outcome measures plus adequate blinding, and further comparative studies with greater patient numbers are required.


Asunto(s)
Trasplante Óseo , Fémur , Colgajos Tisulares Libres , Fémur/irrigación sanguínea , Fémur/trasplante , Colgajos Tisulares Libres/irrigación sanguínea , Colgajos Tisulares Libres/trasplante , Humanos
7.
J Evol Biol ; 31(8): 1109-1126, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29746729

RESUMEN

Phenotypic polymorphism in cryptic species is widespread. This may evolve in response to search image use by predators exerting negative frequency-dependent selection on intraspecific colour morphs, 'apostatic selection'. Evidence exists to indicate search image formation by predators and apostatic selection operating on wild prey populations, though not to demonstrate search image use directly resulting in apostatic selection. The present study attempted to address this deficiency, using British Lepidoptera active in winter as a model system. It has been proposed that the typically polymorphic wing colouration of these species represents an anti-search image adaptation against birds. To test (a) for search image-driven apostatic selection, dimorphic populations of artificial moth-like models were established in woodland at varying relative morph frequencies and exposed to predation by natural populations of birds. In addition, to test (b) whether abundance and degree of polymorphism are correlated across British winter-active moths, as predicted where search image use drives apostatic selection, a series of phylogenetic comparative analyses were conducted. There was a positive relationship between artificial morph frequency and probability of predation, consistent with birds utilizing search images and exerting apostatic selection. Abundance and degree of polymorphism were found to be positively correlated across British Lepidoptera active in winter, though not across all taxonomic groups analysed. This evidence is consistent with polymorphism in this group having evolved in response to search image-driven apostatic selection and supports the viability of this mechanism as a means by which phenotypic and genetic variation may be maintained in natural populations.


Asunto(s)
Evolución Biológica , Aves/fisiología , Mariposas Nocturnas/fisiología , Pigmentación , Conducta Predatoria , Estaciones del Año , Animales , Alas de Animales
8.
J Palliat Med ; 16(11): 1350-5, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24063552

RESUMEN

BACKGROUND: Patients are commonly referred to cancer genetics services when all affected family members are deceased. This makes genetic testing and risk assessment more difficult, reducing the benefit from screening and prophylactic treatment. METHODS: Observational, retrospective, cohort study of 508 randomly selected patients referred to a regional cancer genetics unit, using review of case notes to explore whether a simple clinical "3, 2, 1" family history rule could have been used to improve timely and appropriate referrals for genetic assessment. The 3, 2, 1 criteria are: three affected relatives with the same/associated cancers, across two generations, with at least one person affected age <50 years. RESULTS: Most (71% [362]) genetic risk assessment referrals were in unaffected individuals and 22% (80) of these were referred after all affected family members had died, including 24% (19) who lost their last remaining affected relative in the previous year. Most (59% [301]) referrals met all 3, 2, 1 criteria, and 67% of these could have been made earlier in clinical practice. A further 23% (115) met two of the three criteria. CONCLUSION: Using a simple "3, 2, 1" family rule in cancer care and particularly in palliative care could enable earlier cancer genetic risk assessment for unaffected relatives, improving the potential to benefit from targeted screening and intervention.


Asunto(s)
Asesoramiento Genético , Predisposición Genética a la Enfermedad , Neoplasias/genética , Cuidados Paliativos , Derivación y Consulta , Femenino , Pruebas Genéticas , Humanos , Masculino , Estudios Retrospectivos , Medición de Riesgo , Triaje
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