Evaluation of the BAX® System for Detection of Listeria monocytogenes in Foods: Collaborative Study

A multilaboratory study was conducted to compare the automated BAX® system and the standard cultural methods for detection of Listeria monocytogenes in foods. Six food types (frankfurters, soft cheese, smoked salmon, raw, ground beef, fresh radishes, and frozen peas) were analyzed by each method. For each food type, 3 inoculation levels were tested: high (average of 2 CFU/g), low (average of 0.2 CFU/g) and uninoculated controls. A total of 25 laboratories representing government and industry participated. Of the 2335 samples analyzed, 1109 were positive by the BAX system and 1115 were positive by the standard method. A Chi square analysis of each of the 6 food types, at the 3 inoculation levels tested, was performed. For all foods, except radishes, the BAX system performed as well as or better than the standard reference methods based on the Chi square results.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Evaluation of a Home Visiting and Befriending Scheme for Young Mothers: Newpin

Befriending schemes to support families with young children are now widespread in the United Kingdom. One such scheme, Newpin, which aims to prevent child abuse is described. Evaluation compared those recruited to befriend as well as those befriended. Assessments at baseline and 6 months' follow-up comprised interviews with mothers, developmental assessments of the children and observation of mother–child interaction using video tapes. All assessments were conducted in the home and similar measures were applied to a control sample in an area where a Newpin scheme was planned. Newpin recruits, whether befrienders or befriended had high rates of adverse early experiences, but depression was more common amongst those referred for befriending. Approximately a third did not sustain involvement in the scheme, but those that did were more likely to have had training as volunteers and mental health problems of more than 2 years' duration.

Mallards (Anas platyrhynchos) and wastewater ponds, Part II: Developmental, physiological, morphological and behavioural effects of ingestion of secondary clarified effluent water

Rather than migrating, mallard ducks may choose to overwinter in northern cities on open-water thermal refuges, such as municipal wastewater treatment ponds, which in Edmonton, Canada, stay ≥10°C during frigid winter months. Refuging mallards spend appreciable time daily on these ponds and hydrate using secondary clarified municipal wastewater (SCEW). We aimed to determine if SCEW ingestion affected mallard health. To this end, we gavaged newly hatched mallards (domesticated Pekin strain) over their first month with SCEW, as well as water representing negative and positive controls (municipal tap water, and the primary active ingredient from birth control pills, 17α-ethinyl estradiol (EE2), respectively). The gavage of SCEW did not affect mass of the body, liver, spleen or heart, but was associated with small increases in beak and wing chord length. In the positive control, EE2 gavage caused similar responses, but also increased tarsus and phallus length. The increases likely owed to the stimulatory effects of estrogenic substances on bone and phallus development. For the biotransformation enzyme CYP2H1, gene expression was numerically increased by both SCEW and EE2. In terms of behavior, SCEW and EE2 gavage reduced two infrequently detected behaviours, pecking and resting alone. Our results suggest that SCEW ingestion would be unlikely to cause any overt health effects in adults, but may evoke subtle, covert effects nevertheless.

The Role of Sulfur Dioxide in Stratospheric Aerosol Formation Evaluated Using In-Situ Measurements in the Tropical Lower Stratosphere

Stratospheric aerosols (SAs) are a variable component of the Earth's albedo that may be intentionally enhanced in the future to offset greenhouse gases (geoengineering). The role of tropospheric-sourced sulfur dioxide (SO₂) in maintaining background SAs has been debated for decades without in-situ measurements of SO₂ at the tropical tropopause to inform this issue. Here we clarify the role of SO₂ in maintaining SAs by using new in-situ SO₂ measurements to evaluate climate models and satellite retrievals. We then use the observed tropical tropopause SO₂ mixing ratios to estimate the global flux of SO₂ across the tropical tropopause. These analyses show that the tropopause background SO₂ is about 5 times smaller than reported by the average satellite observations that have been used recently to test atmospheric models. This shifts the view of SO₂ as a dominant source of SAs to a near-negligible one, possibly revealing a significant gap in the SA budget.

Interferon beta overexpression attenuates adipose tissue inflammation and high-fat diet-induced obesity and maintains glucose homeostasis

The worldwide prevalence of obesity is increasing, raising health concerns regarding obesity-related complications. Chronic inflammation has been characterized as a major contributor to the development of obesity and obesity-associated metabolic disorders. The purpose of the current study is to assess whether overexpression of interferon beta (IFNβ1), an immune-modulating cytokine, will attenuate high fat diet-induced adipose inflammation and protect animals against obesity development. Using hydrodynamic gene transfer to elevate and sustain blood concentration of IFNβ1 in mice fed a high fat diet, we showed that overexpression of Ifnβ1 gene markedly suppressed immune cell infiltration into adipose tissue, and attenuated production of pro-inflammatory cytokines. Systemically, IFNβ1 blocked adipose tissue expansion and body weight gain, independent of food intake. Possible browning of white adipose tissue might also contribute to blockade of weight gain. More importantly, IFNβ1 improved insulin sensitivity and glucose homeostasis. These results suggest that targeting inflammation represents a practical strategy to block the development of obesity and its related pathologies. In addition, IFNβ1-based therapies have promising potential for clinical applications for the prevention and treatment of various inflammation-driven pathologies.

Genetic variants associated with subjective well-being, depressive symptoms, and neuroticism identified through genome-wide analyses

Very few genetic variants have been associated with depression and neuroticism, likely because of limitations on sample size in previous studies. Subjective well-being, a phenotype that is genetically correlated with both of these traits, has not yet been studied with genome-wide data. We conducted genome-wide association studies of three phenotypes: subjective well-being (n = 298,420), depressive symptoms (n = 161,460), and neuroticism (n = 170,911). We identify 3 variants associated with subjective well-being, 2 variants associated with depressive symptoms, and 11 variants associated with neuroticism, including 2 inversion polymorphisms. The two loci associated with depressive symptoms replicate in an independent depression sample. Joint analyses that exploit the high genetic correlations between the phenotypes (|ρ^| ≈ 0.8) strengthen the overall credibility of the findings and allow us to identify additional variants. Across our phenotypes, loci regulating expression in central nervous system and adrenal or pancreas tissues are strongly enriched for association.

Does natural selection favour taller stature among the tallest people on earth?

The Dutch are the tallest people on earth. Over the last 200 years, they have grown 20 cm in height: a rapid rate of increase that points to environmental causes. This secular trend in height is echoed across all Western populations, but came to an end, or at least levelled off, much earlier than in The Netherlands. One possibility, then, is that natural selection acted congruently with these environmentally induced changes to further promote tall stature among the people of the lowlands. Using data from the LifeLines study, which follows a large sample of the population of the north of The Netherlands (n = 94 516), we examined how height was related to measures of reproductive success (as a proxy for fitness). Across three decades (1935-1967), height was consistently related to reproductive output (number of children born and number of surviving children), favouring taller men and average height women. This was despite a later age at first birth for taller individuals. Furthermore, even in this low-mortality population, taller women experienced higher child survival, which contributed positively to their increased reproductive success. Thus, natural selection in addition to good environmental conditions may help explain why the Dutch are so tall.

Receiving Instrumental Support in Late Parent-Child Relationships and Parental Depression

OBJECTIVES

This study investigates the role of gender, functional limitations, and social interaction in the association between instrumental support from adult children and parental depression. We apply self-determination theory to hypothesize about the role of physical needs and social resources on parental depression in a European context.

METHOD

A sample of 6,268 parents older than 65 who have nonresident children from the first wave of Survey of Health, Ageing and Retirement in Europe (2004) is analyzed. We estimate logistic regression models to test for the association between instrumental support and depression. Physical needs, gender, and social interaction are used as moderators.

RESULTS

Net of core factors that contribute to depression, including previous history of depression, there is a U-shaped pattern between receiving instrumental support and depression that persists across country regimes. For respondents with medium physical limitations, too little or too frequent support from children is associated with higher depression. For respondents with severe limitations, receiving at least some support is better than receiving none at all. The receipt of too frequent support from children increases the level of depression more for women than men. All interaction effects are comparable across country regimes.

DISCUSSION

Heterogeneity in physical needs and resources of older individuals must be taken into account when assessing the effects of instrumental support on mental health.

The impact of humanitarian context conditions and individual characteristics on aid worker retention

High employee turnover rates constitute a major challenge to effective aid provision. This study examines how features of humanitarian work and aid workers' individual characteristics affect retention within one humanitarian organisation, Médecins Sans Frontières (MSF) Holland. The study extends existing research by providing new theoretical explanations of employment opportunities and constraints and by engaging in the first large-scale quantitative analysis of aid worker retention. Using a database of field staff (N=1,955), a logistic regression is performed of the likelihood of reenlistment after a first mission. The findings demonstrate that only 40 per cent of employees reenlist for a second mission with MSF Holland, and that workplace location and security situation, age, and gender have no significant effect. Individuals are less likely to reenlist if they returned early from the first mission for a personal reason, are in a relationship, are medical doctors, or if they come from highly developed countries. The paper reflects on the findings in the light of policy.

Trajectories of Childbearing among HIV Infected Indian Women: A Sequence Analysis Approach

Background

HIV infection closely relates to and deeply affects the reproductive career of those infected. However, little is known about the reproductive career trajectories, specifically the interaction of the timing of HIV diagnosis with the timing and sequencing of reproductive events among HIV infected women. This is the first study to describe and typify this interaction.

Methods

Retrospective calendar data of ever married HIV infected women aged 15-45 attending a HIV clinic in Pune, Maharashtra, Western India (N=622) on reproductive events such as marriage, cohabitation with the partner, use of contraception, pregnancy, childbirth and HIV diagnosis were analyzed using sequence analysis and multinomial logistic regression.

Results

Optimal matching revealed three distinct trajectories: 1) HIV diagnosis concurrent with childbearing (40.7%), 2) HIV diagnosis after childbearing (32.1%), and 3) HIV diagnosis after husband’s death (27.2%). Multinomial logistic regression (trajectory 1 = baseline) showed that women who got married before the age of 21 years and who had no or primary level education had a significantly higher risk of knowing their HIV status either after childbearing or close to their husband’s death. The risk of HIV diagnosis after husband’s death was also higher among rural women and those who were diagnosed before 2005.

Conclusions

Three distinct patterns of interaction of timing of HIV diagnosis with timing and sequencing of events in the reproductive career were observed that have clear implications for (i) understanding of the individual life planning process in the context of HIV, (ii) formulation of assumptions for estimating HIV infected women in need of PMTCT services, and (iii) provision of care services.

Characterizing spatial uncertainty when integrating social data in conservation planning

Recent conservation planning studies have presented approaches for integrating spatially referenced social (SRS) data with a view to improving the feasibility of conservation action. We reviewed the growing conservation literature on SRS data, focusing on elicited or stated preferences derived through social survey methods such as choice experiments and public participation geographic information systems. Elicited SRS data includes the spatial distribution of willingness to sell, willingness to pay, willingness to act, and assessments of social and cultural values. We developed a typology for assessing elicited SRS data uncertainty which describes how social survey uncertainty propagates when projected spatially and the importance of accounting for spatial uncertainty such as scale effects and data quality. These uncertainties will propagate when elicited SRS data is integrated with biophysical data for conservation planning and may have important consequences for assessing the feasibility of conservation actions. To explore this issue further, we conducted a systematic review of the elicited SRS data literature. We found that social survey uncertainty was commonly tested for, but that these uncertainties were ignored when projected spatially. Based on these results we developed a framework which will help researchers and practitioners estimate social survey uncertainty and use these quantitative estimates to systematically address uncertainty within an analysis. This is important when using SRS data in conservation applications because decisions need to be made irrespective of data quality and well characterized uncertainty can be incorporated into decision theoretic approaches.

Non-linear associations between stature and mate choice characteristics for American men and their spouses

OBJECTIVES

Although male height is positively associated with many aspects of mate quality, average height men attain higher reproductive success in US populations. We hypothesize that this is because the advantages associated with taller stature accrue mainly from not being short, rather than from being taller than average. Lower fertility by short men may be a consequence of their and their partner's lower scores on aspects of mate quality. Taller men, although they score higher on mate quality compared to average height men, may have lower fertility because they are more likely to be paired with taller women, who are potentially less fertile.

METHODS

We analyzed data from The Integrated Health Interview Series (IHIS) of the United States (N = 165,606). Segmented regression was used to examine patterns across the height continuum.

RESULTS

On all aspects of own and partner quality, shorter men scored lower than both average height and taller men. Height more strongly predicted these aspects when moving from short to average height, than when moving from average to taller heights. Women of a given height who scored lower on mate quality also had shorter partners.

CONCLUSIONS

Shorter men faced a double disadvantage with respect to both their own mate quality and that of their spouses. Scores of taller men were only marginally higher than those of average height men, suggesting that being tall is less important than not being short. Although effect sizes were small, our results may partly explain why shorter and taller men have lower fertility than those of average stature.

Fertility in Advanced Societies: A Review of Research: La fécondité dans les sociétés avancées: un examen des recherches

This paper provides a review of fertility research in advanced societies, societies in which birth control is the default option. The central aim is to provide a comprehensive review that summarizes how contemporary research has explained ongoing and expected fertility changes across time and space (i.e., cross- and within-country heterogeneity). A secondary aim is to provide an analytical synthesis of the core determinants of fertility, grouping them within the analytical level in which they operate. Determinants are positioned at the individual and/or couple level (micro-level), social relationships and social networks (meso-level); and, by cultural and institutional settings (macro-level). The focus is both on the quantum and on the tempo of fertility, with a particular focus on the postponement of childbearing. The review incorporates both theoretical and empirical contributions, with attention placed on empirically tested research and whether results support or falsify existing theoretical expectations. Attention is also devoted to causality and endogeneity issues. The paper concludes with an outline of the current challenges and opportunities for future research.

TU-F-213AB-01: Diagnostic Workforce and Manpower Survey

Since AAPM Report No. 33 on Diagnostic Radiology Physics staffing is more than 20 years old, the Diagnostic Work and Workforce Study Subcommittee (DWWSS) of the Professional Council was formed to conduct a new study and update the data. The intent of the DWWSS study has two goals. First, it wanted to assess the number of FTE diagnostic physicists needed to support the QC, acceptance tests, radiation safety and other clinical functions for various imaging modalities, such as: CT scanners, MRI units, angiography rooms, ultrasound units, nuclear medicine imagers and other equipment. For example, the preliminary results indicate that the median annual physics support for one CT scanner is 0.007 FTE or 12.6 hours per unit. Second, the study wanted to provide an estimate of the cost of these physics services in terms of a fraction of a dollar per patient examination performed. For example, the cost for physics support of CT would be $0.27 for each CT procedure. This information would be similar to the Abt study conducted in Radiation Oncology. Radiation therapy physicists have utilized the Abt studies to generate re-imbursement for physics services and to justify financially the cost of their work efforts. Appropriate recognition for physics efforts in Diagnostic Radiology has never been properly quantified nor appreciated. With all the current and future changes occurring in healthcare, the information from the DWWSS survey could be important to the future of diagnostic physicists. Although diagnostic physicists are involved with many other activities such as teaching of residents and research, information about the clinical equipment support effort could be used to assess diagnostic physics staffing needs. The goals of the DWWSS study and the preliminary findings will be presented.

OBJECTIVE

1. Present the goals of the DWWSS Diagnostic Physicist Survey.2. Present potential benefits to the AAPM members from this survey.3. Present findings from the preliminary analysis of the survey.

TU-G-211-01: New Member Symposium

As a new member of the AAPM, it's easy to feel overwhelmed by the size and complexity of the association and to be unaware of the benefits and opportunities available to members. At this year's AAPM national meeting in Charlotte, we will host a New Member Symposium, where you can learn more about the organization, member resources, opportunities to get involved, and about topics of particular interest to new professionals. We encourage you to take advantage of this great opportunity to learn valuable information and to grow your professional network. Following an introduction from Dr. Gary A. Ezzell, the AAPM President; Michael Woodward of the AAPM staff will provide a crash course on the AAPM structure and organization, as well as some pointers on navigating the website. Next will be Dr. Michael Mills presenting on the current state of the U.S. Medical Physics Workforce, Staffing, Supply & Demand, and Limited Residency slots. Registered attendees will receive a raffle ticket for entry in a drawing to win a complimentary registration for the 2013 Annual Meeting in Indianapolis. In addition, all new members who register for the Symposium will receive a drink ticket good for one complimentary beer served after the New Member Symposium during the social with committee chairs from 4 AAPM Councils: Science, Education, Professional, and Administrative.

Why do people postpone parenthood? Reasons and social policy incentives

BACKGROUND

Never before have parents in most Western societies had their first children as late as in recent decades. What are the central reasons for postponement? What is known about the link between the delay of childbearing and social policy incentives to counter these trends? This review engages in a systematic analysis of existing evidence to extract the maximum amount of knowledge about the reasons for birth postponement and the effectiveness of social policy incentives.

METHODS

The review followed the PRISMA procedure, with literature searches conducted in relevant demographic, social science and medical science databases (SocINDEX, Econlit, PopLine, Medline) and located via other sources. The search focused on subjects related to childbearing behaviour, postponement and family policies. National, international and individual-level data sources were also used to present summary statistics.

RESULTS

There is clear empirical evidence of the postponement of the first child. Central reasons are the rise of effective contraception, increases in women's education and labour market participation, value changes, gender equity, partnership changes, housing conditions, economic uncertainty and the absence of supportive family policies. Evidence shows that some social policies can be effective in countering postponement.

CONCLUSIONS

The postponement of first births has implications on the ability of women to conceive and parents to produce additional offspring. Massive postponement is attributed to the clash between the optimal biological period for women to have children with obtaining additional education and building a career. A growing body of literature shows that female employment and childrearing can be combined when the reduction in work-family conflict is facilitated by policy intervention.

The Impact of Subjective Work Control, Job Strain and Work-Family Conflict on Fertility Intentions: a European Comparison

The link between employment and fertility is often only examined by focussing on women's labour market status or the impact of part- versus full-time employment. This study introduces a new explanation by extending research to examine how women's subjective perceptions of control or autonomy over work, job strain and work-family conflict influence fertility intentions. National-level measures of childcare enrolment under the age of three and the occurrence of part-time work are also included to examine their relation to fertility intentions and their interplay with perceptions of work. Using data from 23 countries from the 2004/5 European Social Survey (ESS), multilevel logistic regression models of fertility intentions are estimated separately for women without children and women with one child. Women with higher levels of work control are significantly more likely to intend to have a second child. Higher levels of job strain (time pressure) significantly lower fertility intentions for mothers in contexts where childcare availability is low. The prevalence of part-time work amongst the female work force significantly predicts the intention to become a mother but has different effects for women who work part-time themselves compared with full-time employees.