Higher Apparent Gas Transfer Velocities for CO Compared to CH in Small Lakes.

Large greenhouse gas emissions occur via the release of carbon dioxide (CO) and methane (CH) from the surface layer of lakes. Such emissions are modeled from the air-water gas concentration gradient and the gas transfer velocity (). The links between and the physical properties of the gas and water have led to the development of methods to convert between gases through Schmidt number normalization.

Integrated approach towards quantifying carbon dioxide and methane release from waste stabilization ponds.

Accurate estimations of gaseous emissions and carbon sequestration in wastewater processing are essential for the design, operation and planning of treatment infrastructure, particularly considering greenhouse gas reduction targets. In this study, we look at the interplay between biological productivity, hydrodynamics and evasion of carbon-based greenhouse gases (GHG) through diffusion and ebullition in order to provide direction for more accurate assessments of their emissions from waste stabilization ponds (WSPs). The ponds stratified in the day and mixed at night.

Turbulence in a small boreal lake: Consequences for air-water gas exchange.

The hydrodynamics within small boreal lakes have rarely been studied, yet knowing whether turbulence at the air-water interface and in the water column scales with metrics developed elsewhere is essential for computing metabolism and fluxes of climate-forcing trace gases. We instrumented a humic, 4.7 ha, boreal lake with two meteorological stations, three thermistor arrays, an infrared (IR) camera to quantify surface divergence, obtained turbulence as dissipation rate of turbulent kinetic energy () using an acoustic Doppler velocimeter and a temperature-gradient microstructure profiler, and conducted chamber measurements for short periods to obtain fluxes and gas transfer velocities ().

Effects of climate change and episodic heat events on cyanobacteria in a eutrophic polymictic lake.

Mixing regime and CO availability may control cyanobacterial blooms in polymictic lakes, but the underlying mechanisms still remain unclear. We integrated detailed results from a natural experiment comprising an average-wet year (2011) and one with heat waves (2012), a long-term meteorological dataset (1960-2010), historical phosphorus concentrations and sedimentary pigment records, to determine the mechanistic controls of cyanobacterial blooms in a eutrophic polymictic lake. Intense warming in 2012 was associated with: 1) increased stability of the water column with buoyancy frequencies exceeding 40 cph at the surface, 2) high phytoplankton biomass in spring (up to 125 mg WW L), 3) reduced downward transport of heat and 4) depleted epilimnetic CO concentrations.

Ecology under lake ice.

Winter conditions are rapidly changing in temperate ecosystems, particularly for those that experience periods of snow and ice cover. Relatively little is known of winter ecology in these systems, due to a historical research focus on summer 'growing seasons'. We executed the first global quantitative synthesis on under-ice lake ecology, including 36 abiotic and biotic variables from 42 research groups and 101 lakes, examining seasonal differences and connections as well as how seasonal differences vary with geophysical factors.

A global database of lake surface temperatures collected by in situ and satellite methods from 1985-2009.

Global environmental change has influenced lake surface temperatures, a key driver of ecosystem structure and function. Recent studies have suggested significant warming of water temperatures in individual lakes across many different regions around the world. However, the spatial and temporal coherence associated with the magnitude of these trends remains unclear.

Early-life school, neighborhood, and family influences on adult health: a multilevel cross-classified analysis of the Aberdeen children of the 1950s study.

Lifetime exposures to adverse social environments influence adult health, as do exposures in early life. It is usual to examine the influences of school on teenage health and of adult area of residence on adult health. We examined the combined long-term association of the school attended, as well as the area of residence in childhood, with adult health.

Does perceived physical attractiveness in adolescence predict better socioeconomic position in adulthood? Evidence from 20 years of follow up in a population cohort study.

There is believed to be a 'beauty premium' in key life outcomes: it is thought that people perceived to be more physically attractive have better educational outcomes, higher-status jobs, higher wages, and are more likely to marry. Evidence for these beliefs, however, is generally based on photographs in hypothetical experiments or studies of very specific population subgroups (such as college students). The extent to which physical attractiveness might have a lasting effect on such outcomes in 'real life' situations across the whole population is less well known.

Using natural experiments to evaluate population health interventions: new Medical Research Council guidance.

Natural experimental studies are often recommended as a way of understanding the health impact of policies and other large scale interventions. Although they have certain advantages over planned experiments, and may be the only option when it is impossible to manipulate exposure to the intervention, natural experimental studies are more susceptible to bias. This paper introduces new guidance from the Medical Research Council to help researchers and users, funders and publishers of research evidence make the best use of natural experimental approaches to evaluating population health interventions.

'The Anglo-Saxon disease': a pilot study of the barriers to and facilitators of the use of randomised controlled trials of social programmes in an international context.

Background: There appears to be considerable variation between different national jurisdictions and between different sectors of public policy in the use of evidence and particularly the use of randomised controlled trials (RCTs) to evaluate non-healthcare sector programmes.

Methods: As part of a wider study attempting to identify RCTs of public policy sector programmes and the reasons for variation between countries and sectors in their use, we carried out a pilot study which interviewed 10 policy makers and researchers in six countries to elicit views on barriers to and facilitators of the use of RCTs for social programmes.

Results: While in common with earlier studies, those interviewed expressed a need for unambiguous findings, timely results and significant effect sizes, users could, in fact, be ambivalent about robust methods and robust answers about what works, does not work or makes no difference, particularly where investment or a policy announcement was planned.

Evidence in the development of health policy.

For over a century and a half, reformers, researchers and politicians have complained that social and public health policy is not based on evidence. Linear models of knowledge transfer gaps are consistently shown to be poor predictors of research uptake. Public health research, in particular, involves more elements than the linear biomedical model of translation into healthcare products or interventions.

"Getting sicker quicker": does living in a more deprived neighbourhood mean your health deteriorates faster?

Data from the longitudinal West of Scotland Twenty-07 STUDY: Health in the Community was used to examine whether, over a 20 year period, the self-reported health of people living in deprived areas became poorer faster compared to those living in more affluent areas. Three cohorts (born in the early 1930s, 1950s and 1970s) are included, covering 60 years of the life span. Using multilevel growth curve models, a 40% probability of reporting poor health was predicted among residents of more deprived areas at an earlier age (66) compared to those living in more affluent areas (83).

Is proximity to a food retail store associated with diet and BMI in Glasgow, Scotland?

Background: Access to healthy food is often seen as a potentially important contributor to diet. Policy documents in many countries suggest that variations in access contribute to inequalities in diet and in health. Some studies, mostly in the USA, have found that proximity to food stores is associated with dietary patterns, body weight and socio-economic differences in diet and obesity, whilst others have found no such relationships.

Good intentions and received wisdom are not good enough: the need for controlled trials in public health.

In the 1970s Archie Cochrane noted that many healthcare procedures and forms of organisation lacked evidence of effectiveness and efficiency, and argued for improved methods of evaluation, moving from clinical opinion and observation to randomised controlled trials (RCTs). His arguments gradually became accepted in medicine, but there has been considerable resistance among policymakers and researchers to their application to social and public health interventions. This essay argues that opposition to RCTs in public health is often based on a false distinction between healthcare and community settings, and sometimes on a misunderstanding of the principles of RCTs in health care.

Health status and health behaviours in neighbourhoods: a comparison of Glasgow, Scotland and Hamilton, Canada.

Health status has been demonstrated to vary by neighbourhood socioeconomic status (SES). However, neighbourhood effects may vary between countries. In this study, neighbourhood variations in health outcomes are compared across four socially contrasting neighbourhoods in Glasgow, Scotland and Hamilton, Ontario Canada.

Are secondary data sources on the neighbourhood food environment accurate? Case-study in Glasgow, UK.

Objectives: To assess the validity of a publicly available list of food stores through field observations of their existence, in order to contribute to research on neighbourhood food environments and health.

Methods: All multiple-owned supermarkets, and a 1 in 8 sample of other food outlets, listed in 1997 and 2007 in the public register of food premises held by Glasgow City Council, Scotland, were visited to establish whether they were trading as foodstores. Postcode sectors in which foodstores were located were classified into least, middling and most deprived neighbourhoods.

The socio-spatial distribution of alcohol outlets in Glasgow city.

Aims: The aim of this study was to examine the distribution of alcohol outlets by area deprivation across Glasgow, Scotland.

Methods: All alcohol outlets were mapped and density per 1000 residents and proximity to nearest outlet calculated across quintiles of area deprivation.

Results: The socio-spatial distribution of alcohol outlets varies by deprivation across Glasgow but not systematically.

The food retail environment and area deprivation in Glasgow City, UK.

It has previously been suggested that deprived neighbourhoods within modern cities have poor access to general amenities, for example, fewer food retail outlets. Here we examine the distribution of food retailers by deprivation in the City of Glasgow, UK.We obtained a list of 934 food retailers in Glasgow, UK, in 2007, and mapped these at address level.

Does IQ explain socio-economic differentials in total and cardiovascular disease mortality? Comparison with the explanatory power of traditional cardiovascular disease risk factors in the Vietnam Experience Study.

Aims: The aim of this study was to examine the explanatory power of intelligence (IQ) compared with traditional cardiovascular disease (CVD) risk factors in the relationship of socio-economic disadvantage with total and CVD mortality, that is the extent to which IQ may account for the variance in this well-documented association.

Methods And Results: Cohort study of 4289 US male former military personnel with data on four widely used markers of socio-economic position (early adulthood and current income, occupational prestige, and education), IQ test scores (early adulthood and middle-age), a range of nine established CVD risk factors (systolic and diastolic blood pressure, total blood cholesterol, HDL cholesterol, body mass index, smoking, blood glucose, resting heart rate, and forced expiratory volume in 1 s), and later mortality. We used the relative index of inequality (RII) to quantify the relation between each index of socio-economic position and mortality.

A translational framework for public health research.

Background: The paradigm of translational medicine that underpins frameworks such as the Cooksey report on the funding of health research does not adequately reflect the complex reality of the public health environment. We therefore outline a translational framework for public health research.

Discussion: Our framework redefines the objective of translation from that of institutionalising effective interventions to that of improving population health by influencing both individual and collective determinants of health.