A prospectus for ethical analysis of ageing individuals' responsibility to prevent cognitive decline

As the world's population ages, governments and non‐governmental organizations in developed countries are promoting healthy cognitive ageing to reduce the rate of age‐related cognitive decline and sustain economic productivity in an ageing workforce. Recommendations from the Productivity Commission (Australia), Dementia Australia, Government Office for Science (UK), Presidential Commission for the Study of Bioethical Issues (USA), Institute of Medicine (USA), among others, are encouraging older adults to engage in mental, physical, and social activities. These lifestyle recommendations for healthy cognitive ageing are timely and well supported by scientific evidence but they make implicit normative judgments about the responsibility of ageing individuals to prevent cognitive decline. Ethical tensions arise when this individual responsibility collides with social and personal realities of ageing populations. First, we contextualize the priority given to healthy cognitive ageing within the current brain‐based medical and social discourses. Second, we explore the individual responsibility by examining the economic considerations, medical evidence and individual interests that relate to the priority given to healthy cognitive ageing. Third, we identify three key ethical challenges for policymakers seeking to implement lifestyle recommendations as an effective population‐level approach to healthy cognitive ageing. The result is a prospectus for future in‐depth analysis of ethical tensions that arise from current policy discussions of healthy cognitive ageing.     

Immunosenescence and Vaccination

The problems associated with the ageing immune system and vaccination were discussed recently at an international workshop at the Jenner Institute for Vaccine Research, Compton, UK, 6–7 October, 2005. This is a commentary on that session. The meeting included discussions on T and B cell differentiation and ageing, as well as dendritic cell and neutrophil data, with the emphasis on T cell immunosenescence, perceived as the most important hindrance to satisfactory responses to vaccines in the elderly. The main questions to be addressed in this context are the reasons for dysfunctionality of T cells in the elderly and what to do to improve T cell function. Several of the major reasons for poor T cell responses in the elderly were discussed; however, many important questions remain: The next meeting at the Jenner Institute may already be able to provide some of the answers to these questions, which have serious implications for public health issues in increasingly elderly populations.     

Estimate of deaths attributable to passive smoking among UK adults: database analysis

Objective To estimate deaths from passive smoking in employees of the hospitality industry as well as in the general workforce and general population of the United Kingdom.Design Calculation, using the formula for population attributable proportion, of deaths likely to have been caused by passive smoking at home and at work in the UK according to occupation. Sensitivity analyses to examine impact of varying assumptions regarding prevalence and risks of exposure.Setting National UK databases of causes of death, employment, structure of households, and prevalences of active and passive smoking.Main outcome measures Estimates of deaths due to passive smoking according to age group (< 65 or ≥ 65) and site of exposure (domestic or workplace).Results Across the United Kingdom as a whole, passive smoking at work is likely to be responsible for the deaths of more than two employed people per working day (617 deaths per year), including 54 deaths in the hospitality industry each year. Each year passive smoking at home might account for another 2700 deaths in persons aged 20-64 years and 8000 deaths among people aged ≥ 65.Conclusion Exposure at work might contribute up to one fifth of all deaths from passive smoking in the general population aged 20-64 years, and up to half of such deaths among employees of the hospitality industry. Adoption of smoke free policies in all workplaces and reductions in the general prevalence of active smoking would lead to substantial reductions in these avoidable deaths.     

Modelling distributional trends to inform conservation strategies for an endangered species

Aim Species loss has increased significantly over the last 1000 years and is ultimately attributed to the direct and indirect consequences of increased human population growth across the planet. A growing number of species are becoming endangered and require human intervention to prevent their local extirpation or complete extinction. Management strategies aimed at mitigating a species loss can benefit greatly from empirical approaches that indicate the rate of decline of a species providing objective information on the need for immediate conservation actions, e.g. captive breeding; however, this is rarely employed. The current study used a novel method to examine the distributional trends of a model endangered species, the freshwater pearl mussel, Margaritifera margaritifera (L.). Location United Kingdom and Republic of Ireland. Methods Using species presence data within 10‐km grid squares since records began three‐parameter logistic regression curves were fitted to extrapolate an estimated date of regional extinction. Results This study has shown that freshwater pearl mussel distribution has contracted since known historical records and outlier populations were lost first. Within the United Kingdom and Republic of Ireland, distribution loss has been greatest in Scotland, Northern Ireland, Wales and England, respectively, with the Republic of Ireland containing the highest relative proportion of M. margaritifera distribution, in 1998. Main conclusions This study provides empirical evidence that this species could become extinct throughout countries within the United Kingdom within 170 years under the current trends and emphasizes that regionally specific management strategies need to be implemented to prevent extirpation of this species.     

The surgical workforce crisis: rising to the challenge of caring for an aging America

In the past century, both the field of surgery and the population it serves have markedly changed. The number of elderly individuals in the United States is rapidly increasing. However, this increase has not been accompanied by commensurate growth in the surgical workforce. As the demographic characteristics of medical students have become more diverse, medical student interest in surgical training has declined. These trends raise two fundamental questions. (1) Will there be enough surgeons to meet the needs of an aging United States population? (2) Who will these surgeons be?     

European red squirrel population dynamics driven by squirrelpox at a gray squirrel invasion interface

Infectious disease introduced by non‐native species is increasingly cited as a facilitator of native population declines, but direct evidence may be lacking due to inadequate population and disease prevalence data surrounding an outbreak. Previous indirect evidence and theoretical models support squirrelpox virus (SQPV) as being potentially involved in the decline of red squirrels (Sciurus vulgaris) following the introduction of the non‐native gray squirrel (Sciurus carolinensis) to the United Kingdom. The red squirrel is a major UK conservation concern and understanding its continuing decline is important for any attempt to mitigate the decline. The red squirrel–gray squirrel system is also exemplary of the interplay between infectious disease (apparent competition) and direct competition in driving the replacement of a native by an invasive species. Time series data from Merseyside are presented on squirrel abundance and squirrelpox disease (SQPx) incidence, to determine the effect of the pathogen and the non‐native species on the native red squirrel populations. Analysis indicates that SQPx in red squirrels has a significant negative impact on squirrel densities and their population growth rate (PGR). There is little evidence for a direct gray squirrel impact; only gray squirrel presence (but not density) proved to influence red squirrel density, but not red squirrel PGR. The dynamics of red SQPx cases are largely determined by previous red SQPx cases, although previous infection of local gray squirrels also feature, and thus, SQPV‐infected gray squirrels are identified as potentially initiating outbreaks of SQPx in red squirrels. Retrospective serology indicates that approximately 8% of red squirrels exposed to SQPV may survive infection during an epidemic. This study further highlights the UK red squirrel – gray squirrel system as a classic example of a native species population decline strongly facilitated by infectious disease introduced by a non‐native species. It is therefore paramount that disease prevention and control measures are integral in attempts to conserve red squirrels in the United Kingdom.     

迁移对害虫抗性演化的影响

利用抗性群体遗传模型研究了迁移对害虫抗性演化的影响。模拟结果表明,迁入比例对害虫种群抗性演化的影响存在一定的阈值。若迁入个体全为敏感(SS)纯合子,而其比例又在阈值以下时,这种迁入对抗性演化无延缓作用;迁入比例在阈值以上时,随比例加大,对抗性延缓作用逐渐增强,加大到某一值时,抗性演化可完全被阻止;若迁入个体携有R基因,则迁入比例在阈值以下时,会促进迁入区害虫种群的抗性演化;在阈值以上时,可延缓或完全阻止害虫种群的抗性演化。处理区害虫种群原有个体的迁出,可加强SS个体迁入对害虫种群抗性演化的影响,而使携R基因的个体的迁入影响减弱。以小菜蛾Plutella xylostella为模型昆虫所作的试验结果表明,模型模拟与验证试验的结果具有较好的一致性,说明抗性模拟模型可用于害虫种群的抗性演化预测和分析。     

Radiological prevalence of Paget's disease of bone in British migrants to Australia.

The radiological prevalence of Paget''s disease among migrants from the United Kingdom to Australia was higher than in a comparable Australian resident population but lower than in a British resident population. A probable explanation is that the migrants carry with them the higher UK risk of developing the disease.     

Overland movement and migration phenology in relation to breeding of Arctic Terns Sterna paradisaea

It is often implicitly assumed that seabirds migrate using marine environments, but this assumption is increasingly being challenged by electronic tracking data. The arrival and departure routes of Arctic Terns breeding on the North Sea coast of the United Kingdom (UK) are unknown but there has been speculation about the possibility of overland migration. Analysis of light-level geolocator data from birds breeding on the Farne Islands suggests that these birds arrived and left their North Sea colony overland via the Irish Sea, rather than taking coastal routes along the east coast of the UK and through the English Channel. In addition, some departing birds may enter the North Atlantic by crossing Ireland rather than through the Irish Sea. The direction of arrival in spring had a more southerly orientation than the direction of autumn departure. The geolocator data allow migration phenology in relation to breeding to be defined and indicated that the birds arrived around 15 days before the first eggs were laid in the colony. Departure timing may be determined by seasonal progression and not markedly influenced by breeding success. This study supports the idea that overland migration may be a more widespread and consistent strategy for seabirds than has been realized.     

Mitochondrial genetic diversity and structure of the European otter (Lutra lutra) in Britain

The European otter (Lutra lutra) is a focus for conservation efforts throughout Europe due to a population decline in recent decades and because of its importance as a biological indicator of the health of rivers and waterways. The aim of this study was to aid the conservation of this species by adding genetic information from samples originating in the United Kingdom (UK), to help build up a picture of the phylogeographic structure of the European otter throughout Europe. This was done by a comparison of 299 base pairs of the mitochondrial DNA control region. Four haplotypes were identified in the UK, one of which has not been found outside the west of the UK in the wild, and one of which was unique. Populations in the UK, and in particular the west were shown to have a higher haplotype diversity than previously found for the European otter in Europe (h = 0.7338 for the 58 UK otters sampled in this study) and an overall nucleotide diversity of π = 0.003. The western UK population was shown to have a high level of genetic distinctiveness. We discuss possible contributory population processes, the importance of the western UK population for the future conservation of the species and comment on future conservation strategies.     

Submitting articles to the BMJ

ObjectiveTo measure the effect of giving out free smoke alarms on rates of fires and rates of fire related injury in a deprived multiethnic urban population.DesignCluster randomised controlled trial.SettingForty electoral wards in two boroughs of inner London, United Kingdom.ParticipantsPrimarily households including elderly people or children and households that are in housing rented from the borough council.Intervention20 050 smoke alarms, fittings, and educational brochures distributed free and installed on request.ResultsGiving out free smoke alarms did not reduce injuries related to fire (rate ratio 1.3; 95% confidence interval 0.9 to 1.9), admissions to hospital and deaths (1.3; 0.7 to 2.3), or fires attended by the fire brigade (1.1; 0.96 to 1.3). Similar proportions of intervention and control households had installed alarms (36/119 (30%) v 35/109 (32%); odds ratio 0.9; 95% confidence interval 0.5 to 1.7) and working alarms (19/118 (16%) v 18/108 (17%); 0.9; 0.4 to 1.8).ConclusionsGiving out free smoke alarms in a deprived, multiethnic, urban community did not reduce injuries related to fire, mostly because few alarms had been installed or were maintained.

What is already known on this topic

In the United Kingdom, residential fires caused 466 deaths and 14 600 non-fatal injuries in 1999The risk of death from fire is associated with socioeconomic classOne study reported an 80% decline in hospitalisations and deaths from residential fires after free smoke alarms were distributed in an area at high risk, but these results may not apply in other settings, and evidence from randomised controlled trials is lacking

What this study adds

Giving out free smoke alarms in a multiethnic poor urban population did not reduce injuries related to fire or firesGiving smoke alarms away may be a waste of resources and of little benefit unless alarm installation and maintenance is assured     

On the Risk of Multiple Sclerosis According to Age at Immigration to South Africa

In a national prevalence study of multiple sclerosis (M.S.) in the Republic of South Africa based on census day 1960 there were 118 individuals with M.S. who were born in Northern Europe (United Kingdom and other parts of North and Central Europe) and who had emigrated to the Republic by 1960. Their prevalence rate was 49 per 100,000 immigrants in comparison with a prevalence of 11 per 100,000 among native-born English-speaking white South Africans.To study the possible effect of age at immigration it was necessary to relate the M.S. immigrants to the appropriate denominator—the population at risk according to age at immigration. The population at risk by age at immigration has been estimated by two methods in an indirect fashion with the assistance of the Bureau of Census (1960) and by surveys of the population at risk 1968-9. Both studies suggest that the risk of developing M.S. was reduced to less than a third of the expected risk among those who immigrated under the age of 15 or 16.This study is further evidence that M.S. is an acquired exogenous disease, the precise nature of which is still not certain but, according to present knowledge, has as its leading contender the class of slow, latent, or temperate viruses.     

Revising the British Red Data List for birds: the biological basis of U.K. conservation priorities

The list of British Red Data birds (Batten et al. 1990) includes 117 species, 109 of which qualified on one or more quantitative criteria referring to rarity, localized distribution, population decline and international importance. A wealth of data on bird population levels and trends in the United Kingdom and Europe has recently become available, allowing refinement and improvement of the criteria for qualification. Here we propose that in assigning priorities for conservation action in the U.K. (Britain and Northern Ireland), three biological axes need to be considered: national threat (measured as rarity, localized distribution and population decline in the U.K.), international importance (the proportion of the European population in the U.K.) and international threat (European/global conservation status). Only the first two of these axes were considered by Batten et al. (1990). Each of these axes has been sub-divided into high, medium and low categories using quantitative thresholds, and from this we produce a national 'conservation cube' (three axes, each with three categories and thus 27 cells). Data permitting, every species in the U.K. can be allocated to one of these cells. We suggest that species high on either (or both) of the national or international threat axes be considered as species of high conservation priority (the red list) and that among the remainder those that rank at least medium on one of the axes be considered as of medium conservation priority (the amber list). All other species are of low conservation priority (the green list). We suggest that this three-axis model could be applicable to other taxa and countries.     

The Emergence of Regional Immigrant Concentrations in USA and Australia: A Spatial Relatedness Approach

This paper examines the patterns of the US and Australian immigration geography and the process of regional population diversification and the emergence of new immigrant concentrations at the regional level. It presents a new approach in the context of human migration studies, focusing on spatial relatedness between individual foreign-born groups as revealed from the analysis of their joint spatial concentrations. The approach employs a simple assumption that the more frequently the members of two population groups concentrate in the same locations the higher is the probability that these two groups can be related. Based on detailed data on the spatial distribution of foreign-born groups in US counties (2000–2010) and Australian postal areas (2006–2011) we firstly quantify the spatial relatedness between all pairs of foreign-born groups and model the aggregate patterns of US and Australian immigration systems conceptualized as the undirected networks of foreign-born groups linked by their spatial relatedness. Secondly, adopting a more dynamic perspective, we assume that immigrant groups with higher spatial relatedness to those groups already concentrated in a region are also more likely to settle in this region in future. As the ultimate goal of the paper, we examine the power of spatial relatedness measures in projecting the emergence of new immigrant concentrations in the US and Australian regions. The results corroborate that the spatial relatedness measures can serve as useful instruments in the analysis of the patterns of population structure and prediction of regional population change. More generally, this paper demonstrates that information contained in spatial patterns (relatedness in space) of population composition has yet to be fully utilized in population forecasting.     

Monitoring Sub-Saharan African Physician Migration and Recruitment Post-Adoption of the WHO Code of Practice: Temporal and Geographic Patterns in the United States

Data monitoring is a key recommendation of the WHO Global Code of Practice on the International Recruitment of Health Personnel, a global framework adopted in May 2010 to address health workforce retention in resource-limited countries and the ethics of international migration. Using data on African-born and African-educated physicians in the 2013 American Medical Association Physician Masterfile (AMA Masterfile), we monitored Sub-Saharan African (SSA) physician recruitment into the physician workforce of the United States (US) post-adoption of the WHO Code of Practice. From the observed data, we projected to 2015 with linear regression, and we mapped migrant physicians’ locations using GPS Visualizer and ArcGIS. The 2013 AMA Masterfile identified 11,787 active SSA-origin physicians, representing barely 1.3% (11,787/940,456) of the 2013 US physician workforce, but exceeding the total number of physicians reported by WHO in 34 SSA countries (N = 11,519). We estimated that 15.7% (1,849/11,787) entered the US physician workforce after the Code of Practice was adopted. Compared to pre-Code estimates from 2002 (N = 7,830) and 2010 (N = 9,938), the annual admission rate of SSA émigrés into the US physician workforce is increasing. This increase is due in large part to the growing number of SSA-born physicians attending medical schools outside SSA, representing a trend towards younger migrants. Projection estimates suggest that there will be 12,846 SSA migrant physicians in the US physician workforce in 2015, and over 2,900 of them will be post-Code recruits. Most SSA migrant physicians are locating to large urban US areas where physician densities are already the highest. The Code of Practice has not slowed the SSA-to-US physician migration. To stem the physician “brain drain”, it is essential to incentivize professional practice in SSA and diminish the appeal of US migration with bolder interventions targeting primarily early-career (age ≤ 35) SSA physicians.     

Substantial genetic structure among stocked and native populations of the European grayling (<Emphasis Type="Italic">Thymallus thymallus</Emphasis>, Salmonidae) in the United Kingdom

While currently in a state of recovery in the United Kingdom (UK), the grayling (Thymallus thymallus) remains of conservation interest due to its historical decline, socio-economic value and the potential impact of hatchery-reared stock fish on the genetic structure and diversity of wild populations. However, little is known about the levels and distribution of genetic diversity among UK grayling populations. To this end, 27 UK populations of grayling were genotyped across 10 microsatellite loci and sequenced at the mtDNA D-Loop. All populations clustered into four higher-level groups: Northern England, Southern England, Wales, and group consisting of a mixture of native and introduced populations. Ten populations showed evidence of bottleneck or founder effects, and the effective population size (Ne) was low in all populations. In most cases, historical stocking records agreed with the genetic relationships revealed in the study. A D-Loop haplotype network supported the groupings observed in the nuclear data, while phylogenetic inference places the UK populations amongst Central European samples. The combined datasets demonstrate that many of the UK populations can be treated as separate Management Units and we recommend that to preserve population specific genetic diversity, that stocking should be an intervention of last resort. However, if stocking is deemed essential, brood stock should originate from the river to be stocked.     

The dendrochronological potential of decayed yew wood

A significant difficulty in the accurate ageing of many of the largest-diameter yew trees (Taxus baccata L.) found in the United Kingdom is their vulnerability to heartwood decay. This has presented a considerable barrier to extending yew chronologies beyond c.330 years into the past. Decayed wood often survives within the sound cylindrical structure of hollow and hollowing yews. Here we present the analysis of such decayed yew wood using a novel wet-scanning technique. Long series for four out of five large hollow yew trees sampled are successfully cross-matched to produce a 374-year-long mean series spanning 1532–1905. These newly dated series extend the previous mean UK yew chronology by 158 years. Although currently undated, the central decayed material from the largest yew at Selborne produces a 196-year series which is likely to include material from the 14th century. Given the number of large hollow yew trees surviving in the UK, this research highlights the potential for using decayed yew wood to improve the ageing of yew trees and extending a regional yew chronology.     

Factors affecting nest predation on forest songbirds in North America

Nest predation is an important factor in the ecology of passerines and can be a large source of mortality for birds. I provide an overview of factors affecting nest predation of passerines in North America with the goal that it may provide some insight into the ecology and management of woodland birds in the United Kingdom. Although several factors influence productivity, nest success is perhaps the most widely measured demographic characteristic of open-cup-nesting birds, and nest predation is usually the largest cause of nest failure. The identity of predator species, and how their importance varies with habitat and landscape factors, must be known for managers and scientists to design effective conservation plans and place research on nest predation in the appropriate context. Recent studies using video surveillance have made significant contributions to our understanding of the relative importance of different predator taxa in North America. Spatial and temporal variation in nest predation can be better understood when landscapes are placed in a biogeographical context and local habitat and nest-site effects are placed in a landscape context. Low productivity resulting from high nest predation is one of several potential causes of bird population declines in North America and the UK. Although the 'forest fragmentation paradigm' from the eastern US may not apply directly to the UK, thinking about avian demographics from a multiscale perspective, and consideration of factors affecting nest predation with knowledge of the dominant predator species, may provide insight into population declines.     

Introduction: Forensic anthropology and interdisciplinarity

Using anatomical feature comparison to consider potential matches from hand images to identify or eliminate suspects in an investigation, commonly relating to those involved in the production of images of child sexual abuse, is an emerging forensic methodology that has become increasingly utilized by police forces within the United Kingdom. This article gives an overview of the development of a process that is based on an understanding of anatomical variation and shows how new approaches can be introduced to forensic investigations. It describes the rationale that led to the development of the investigative methodology within the United Kingdom, and how it is implemented to ensure that comparisons and the subsequent reports are both methodologically sound and admissible in any of the courts within the UK legal jurisdictions.     

Literature review on the role of dietary protein and amino acids in cognitive functioning and cognitive decline

As the population of elderly people is growing rapidly, the number of individuals with dementia and cognitive impairment is also increasing. One of the preventive measures against cognitive decline is diet and different dietary factors have already been investigated. This review provides an overview of studies on dietary protein and cognitive functioning and cognitive decline. Also studies on the individual amino acids that are related to brain function, tryptophan and tyrosine, are discussed. Overall, the role of dietary protein intake on cognitive functioning as well as cognitive decline has hardly been studied; we found eight observational studies and three intervention studies. More studies investigated the role of tryptophan (14 studies) and tyrosine (nine studies) in relation to cognitive functioning, but all these studies were performed in young adult populations and mostly under special conditions. Research in elderly populations, in particular, is warranted. Also more research is needed to come to definitive conclusions and specific recommendations regarding protein intake or intake of specific amino acids for maintaining optimal cognitive functioning.