Adaptive latitudinal variation in Common Blackbird Turdus merula nest characteristics

Nest construction is taxonomically widespread, yet our understanding of adaptive intraspecific variation in nest design remains poor. Nest characteristics are expected to vary adaptively in response to predictable variation in spring temperatures over large spatial scales, yet such variation in nest design remains largely overlooked, particularly amongst open-cup-nesting birds. Here, we systematically examined the effects of latitudinal variation in spring temperatures and precipitation on the morphology, volume, composition, and insulatory properties of open-cup-nesting Common Blackbirds’ Turdus merula nests to test the hypothesis that birds living in cooler environments at more northerly latitudes would build better insulated nests than conspecifics living in warmer environments at more southerly latitudes. As spring temperatures increased with decreasing latitude, the external diameter of nests decreased. However, as nest wall thickness also decreased, there was no variation in the diameter of the internal nest cups. Only the mass of dry grasses within nests decreased with warmer temperatures at lower latitudes. The insulatory properties of nests declined with warmer temperatures at lower latitudes and nests containing greater amounts of dry grasses had higher insulatory properties. The insulatory properties of nests decreased with warmer temperatures at lower latitudes, via changes in morphology (wall thickness) and composition (dry grasses). Meanwhile, spring precipitation did not vary with latitude, and none of the nest characteristics varied with spring precipitation. This suggests that Common Blackbirds nesting at higher latitudes were building nests with thicker walls in order to counteract the cooler temperatures. We have provided evidence that the nest construction behavior of open-cup-nesting birds systematically varies in response to large-scale spatial variation in spring temperatures

Post-fledging habitat selection in a rapidly declining farmland bird, the European turtle dove Streptopelia turtur

Post-fledging survival plays a vital role in the dynamics of bird populations and yet is the least studied avian life-stage. Habitat requirements post-fledging may have important implications for behaviour and survival, especially for declining populations in landscapes that have undergone wide-scale anthropogenic modification, resulting in an altered distribution and composition of habitats. The European Turtle Dove is a widespread but rapidly declining species both within the UK and across Europe. Reduced seed food availability is thought to influence breeding success of this species, but it is not known whether post-fledging survival may also be influenced by seed availability. Here, we use leg-ring radio-tag attachments to monitor post-fledging survival and movements in 15 Turtle Dove nestlings from eight nests monitored during 2014 as part of a wider autecological study. Fledglings remained in close proximity to their nest for three weeks post-tagging, spending more than half their time in the immediate vicinity (within ∼ 20 m) of the nest. 95% of foraging trips during this period were within 329 m of the nest and fledglings selected seed-rich habitat (semi-natural grassland, low-intensity grazing, fallow and quarries). Fledglings that were heavier and in better body condition at seven days old were more likely to survive for 30 days post-fledging, and the proportion of available seed-rich habitat was a strong predictor of nestling weight and condition at seven days old. Whilst our sample size is modest, this study highlights the crucial role of food availability in juvenile survival, both while adults are feeding nestlings, and to recently fledged young, and the potential for agri-environment schemes providing foraging and nesting habitats in close proximity to provide important benefits

First light for avian embryos: eggshell thickness and pigmentation mediate variation in development and UV exposure in wild bird eggs

Article first published online: 29 JUL 20141. The avian embryo's development is influenced by both the amount and the wavelength of the light that passes through the eggshell. Commercial poultry breeders use light of specific wavelengths to accelerate embryonic growth, yet the effects of the variably patterned eggshells of wild bird species on light transmission and embryonic development remain largely unexplored. 2. Here, we provide the first comparative phylogenetic analysis of light transmission, through a diverse range of bird eggshells (74 British breeding species), in relation to the eggshell's thickness, permeability, pigment concentration and surface reflectance spectrum (colour). 3. The percentage of light transmitted through the eggshell was measured in the spectral range 250–700 nm. Our quantitative analyses confirm anecdotal reports that eggshells filter the light of the externally coloured shell. Specifically, we detected a positive relationship between surface eggshell reflectance (‘brightness’) and the percentage of light transmitted through the eggshell, and this relationship was strongest at wavelengths in the human-visible blue-green region of the spectra (c. 435 nm). 4. We show that less light passes through thicker eggshells with greater total pigment concentrations. By contrast, permeability (measured as water vapour conductance) did not covary significantly with light transmission. Eggs of closed-nesting species let more light pass through, compared with open nesters. 5. We postulate that greater light transmission is required to assist embryonic development under low light exposure. Importantly, this result provides an ecological explanation for the repeated evolution of immaculate, white- or pale-coloured eggshells in species nesting in enclosed spaces. 6. Finally, we detected correlative support for the solar radiation hypothesis, in that eggshells of bird species with a longer incubation period let significantly less of the potentially harmful, ultraviolet (UV) light pass through the eggshell. In summary, we demonstrate suites of avian eggshell properties, including eggshell structure and pigmentation, which are consistent with an evolutionary pressure to both enhance and protect embryonic development.Golo Maurer, Steven J. Portugal, Mark E. Hauber, Ivan Mikšík, Douglas G. D. Russell and Phillip Casse

Management of hemiplegic shoulder pain: A UK-wide online survey of physiotherapy and occupational therapy practice

Purpose: The purpose of this study was to explore, via an online survey, how therapists assess, diagnose and manage hemiplegic shoulder pain (HSP) in the United Kingdom. The objectives were to explore (1) how therapists assessed HSP, (2) what the aims of therapy were, (3) what interventions therapists used, (4) what outcome measures therapists used, (5) what training of HSP therapists had, and (6) what barriers therapists experienced in the management of HSP. Methods: An online survey was distributed to physiotherapists (PTs) and occupational therapists (OTs) working in stroke rehabilitation via professional bodies' interest groups. Results: Sixty-seven responses were received: 40 (60%) were PTs and 27 (40%) were OTs. Therapists routinely screened for HSP (n = 59, 89%). When HSP was assessed, 33 (50%) spent 10 min on assessment. Patient-reported pain was used for assessment of HSP by 66 (99%) of respondents. Frequent interventions included positioning (n = 62, 94%), posture re-education (n = 57, 86%), and range of motion exercises (n = 55, 83%). Range of movement was used as an outcome measure by 31 (47%). Sixty (91%) respondents reported receiving training in HSP management. Time constraints (n = 41, 62%) and lack of diagnosis of HSP (n = 33, 54%) were identified as barriers to providing appropriate care to people with HSP. Conclusion: Study findings showed varied practice in the assessment and treatment for HSP and indicate that time constraints are a considerable barrier to the management of these patients. Further research is required to establish best practice which may help improve outcomes and care for people with poststroke shoulder pain

The roles of migratory and resident birds in local avian influenza infection dynamics

Migratory birds are an increasing focus of interest when it comes to infection dynamics and the spread of avian influenza viruses (AIV ). However, we lack detailed understanding of migratory birds’ contribution to local AIV prevalence levels and their downstream socio‐economic costs and threats. To explain the potential differential roles of migratory and resident birds in local AIV infection dynamics, we used a susceptible‐infectious‐recovered (SIR ) model. We investigated five (mutually non‐ exclusive) mechanisms potentially driving observed prevalence patterns: (1) a pronounced birth pulse (e.g. the synchronised annual influx of immunologically naïve individuals), (2) short‐term immunity, (3) increase in susceptible migrants, (4) differential susceptibility to infection (i.e. transmission rate) for migrants and residents, and (5) replacement of migrants during peak migration. SIR models describing all possible combinations of the five mechanisms were fitted to individual AIV infection data from a detailed longitudinal surveillance study in the partially migratory mallard duck (Anas platyrhynchos ). During autumn and winter, the local resident mallard community also held migratory mallards that exhibited distinct AIV infection dynamics. Replacement of migratory birds during peak migration in autumn was found to be the most important mechanism driving the variation in local AIV infection patterns. This suggests that a constant influx of migratory birds, likely immunological naïve to locally circulating AIV strains, is required to predict the observed temporal prevalence patterns and the distinct differences in prevalence between residents and migrants. Synthesis and applications . Our analysis reveals a key mechanism that could explain the amplifying role of migratory birds in local avian influenza virus infection dynamics; the constant flow and replacement of migratory birds during peak migration. Apart from monitoring efforts, in order to achieve adequate disease management and control in wildlife—with knock‐on effects for livestock and humans,—we conclude that it is crucial, in future surveillance studies, to record host demographical parameters such as population density, timing of birth and turnover of migrants

Infection does not increase long-term mortality in patients with acute severe alcoholic hepatitis treated with corticosteroids

AIM: To determine whether infection in patients with acute severe alcoholic hepatitis (AAH) treated with corticosteroids is associated with increased mortality. METHODS: Consecutive patients with AAH were treated with steroids and recruited to the study. Clinically relevant infections (body temperature > 38 °C or < 36 °C for more than 4 h, ascitic neutrophil count > 0.25 ×10(9)/L, consolidation on chest radiograph or clinically relevant positive microbiological culture of bodily fluid) were recorded prospectively. Clinical and laboratory parameters were recorded and survival at 90 d and 6 mo was determined. Univariate analysis of factors associated with 90-d mortality was performed and significant variables included in a multivariate analysis. RESULTS: Seventy-two patients were included in the final analysis (mean age 47.9 years, 26% female, mean discriminant function 53.0). Overall mortality in the group occurred in 15 (21%), 23 (32%) and 31 (43%) at day 28, day 90 and 1 year respectively. 36 (50%) had a clinically relevant infection during their hospitalisation (23 after initiation of steroids). The median time to development of incident infection after commencement of steroids was 10 d. The commonest site of infection was ascites (31%) and bacteraemia (31%) followed by urinary tract (19%) and respiratory tract (8%). Forty-one separate organisms were isolated in 33 patients; the most frequent genus was Escherichia (22%) and Enterococcus (20%). Infection was not associated with 90-d or 1 year mortality but was associated with higher creatinine, model for end-stage liver disease and Lille score. Baseline urea was the only independent predictor of 90-d mortality. CONCLUSION: Clinically relevant infections are common in patients with AAH but are not associated with increased 90-d or 1 year mortality

Analytical Bethe Ansatz for closed and open gl(n)-spin chains in any representation

We present an "algebraic treatment" of the analytical Bethe Ansatz. For this purpose, we introduce abstract monodromy and transfer matrices which provide an algebraic framework for the analytical Bethe Ansatz. It allows us to deal with a generic gl(n)-spin chain possessing on each site an arbitrary gl(n)-representation. For open spin chains, we use the classification of the reflection matrices to treat all the diagonal boundary cases. As a result, we obtain the Bethe equations in their full generality for closed and open spin chains. The classifications of finite dimensional irreducible representations for the Yangian (closed spin chains) and for the reflection algebras (open spin chains) are directly linked to the calculation of the transfer matrix eigenvalues. As examples, we recover the usual closed and open spin chains, we treat the alternating spin chains and the closed spin chain with impurity

Longer wings for faster springs – wing length relates tospring phenology in a long-distanc e migrant across its range

In migratory birds, morphological adaptations for efficient migratory flight often oppose morphological adaptations for efficient behavior during resident periods. This includes adaptations in wing shape for either flying long distances or foraging in the vegetation and in climate-driven variation of body size. In addition, the timing of migratory flights and particularly the timely arrival at local breeding sites is crucial because fitness prospects depend on site-specific phenology. Thus, adaptations for efficient long-distance flights might be also related to conditions at destination areas. For an obligatory long-distance migrant, the common nightingale, we verified that wing length as the aerodynamically important trait, but not structural body size increased from the western to the eastern parts of the species range. In contrast with expectation from aerodynamic theory, however, wing length did not increase with increasing migration distances. Instead, wing length was associated with the phenology at breeding destinations, namely the speed of local spring green-up. We argue that longer wings are beneficial for adjusting migration speed to local conditions for birds breeding in habitats with fast spring green-up and thus short optimal arrival periods. We suggest that the speed of spring green-up at breeding sites is a fundamental variable determining the timing of migration that fine tune phenotypes in migrants across their range

HCV treatment rates and sustained viral response among people who inject drugs in seven UK sites: real world results and modelling of treatment impact.

Hepatitis C virus (HCV) antiviral treatment for people who inject drugs (PWID) could prevent onwards transmission and reduce chronic prevalence. We assessed current PWID treatment rates in seven UK settings and projected the potential impact of current and scaled-up treatment on HCV chronic prevalence. Data on number of PWID treated and sustained viral response rates (SVR) were collected from seven UK settings: Bristol (37-48% HCV chronic prevalence among PWID), East London (37-48%), Manchester (48-56%), Nottingham (37-44%), Plymouth (30-37%), Dundee (20-27%) and North Wales (27-33%). A model of HCV transmission among PWID projected the 10-year impact of (i) current treatment rates and SVR (ii) scale-up with interferon-free direct acting antivirals (IFN-free DAAs) with 90% SVR. Treatment rates varied from <5 to over 25 per 1000 PWID. Pooled intention-to-treat SVR for PWID were 45% genotypes 1/4 [95%CI 33-57%] and 61% genotypes 2/3 [95%CI 47-76%]. Projections of chronic HCV prevalence among PWID after 10 years of current levels of treatment overlapped substantially with current HCV prevalence estimates. Scaling-up treatment to 26/1000 PWID annually (achieved already in two sites) with IFN-free DAAs could achieve an observable absolute reduction in HCV chronic prevalence of at least 15% among PWID in all sites and greater than a halving in chronic HCV in Plymouth, Dundee and North Wales within a decade. Current treatment rates among PWID are unlikely to achieve observable reductions in HCV chronic prevalence over the next 10 years. Achievable scale-up, however, could lead to substantial reductions in HCV chronic prevalence

Innate Sex Differences in the Timing of Spring Migration in a Songbird

In migrating animals protandry is the phenomenon whereby males of a species arrive at the breeding grounds earlier than females. In the present study we investigated the proximate causes of protandry in a migratory songbird, the northern wheatear Oenanthe oenanthe. Previous experiments with caged birds revealed that males and females show differentiated photoperiod-induced migratory habits. However, it remained open whether protandry would still occur without photoperiodic cues. In this study we kept captive first-year birds under constant photoperiod and environmental conditions in a “common garden” experiment. Male northern wheatears started their spring migratory activity earlier than females, even in the absence of environmental cues. This indicates that protandry in the northern wheatear has an endogenous basis with an innate earlier spring departure of males than females