On-Road Development of John Deere 6081 Natural Gas Engine: Final Technical Report, July 1999 - January 2001

Report that discusses John Deere's field development of a heavy-duty natural gas engine. As part of the field development project, Waste Management of Orange County, California refitted four existing trash packers with John Deere's prototype spark ignited 280-hp 8.1 L CNG engines. This report describes the project and also contains information about engine performance, emissions, and driveability

Something in the atmosphere? Michael Chekhov, Deirdre Hurst Du Prey, and a web of practices between acting and dance

This article contextualises principles of Chekhov’s technique within convergent developments in dance by bringing into focus the interesting web of connections between Chekhov’s female colleagues — specifically his associate Deirdre Hurst Du Prey — and key pioneers in the field of dance and dance-mime, including Mary Wigman, Isadora Duncan, Martha Graham and Margaret Barr. Their cross-connections broaden our view on the canon of embodied theatre practice, and also open up reflection on how overlaps between acting- and dance principles may be useful for contemporary embodied theatre practice and its efforts to work across these currently (in the Western conservatoire context) quite segregated disciplines

Comparison of contact patterns relevant for transmission of respiratory pathogens in Thailand and the Netherlands using respondent-driven sampling

Understanding infection dynamics of respiratory diseases requires the identification and quantification of behavioural, social and environmental factors that permit the transmission of these infections between humans. Little empirical information is available about contact patterns within real-world social networks, let alone on differences in these contact networks between populations that differ considerably on a socio-cultural level. Here we compared contact network data that were collected in the Netherlands and Thailand using a similar online respondent-driven method. By asking participants to recruit contact persons we studied network links relevant for the transmission of respiratory infections. We studied correlations between recruiter and recruited contacts to investigate mixing patterns in the observed social network components. In both countries, mixing patterns were assortative by demographic variables and random by total numbers of contacts. However, in Thailand participants reported overall more contacts which resulted in higher effective contact rates. Our findings provide new insights on numbers of contacts and mixing patterns in two different populations. These data could be used to improve parameterisation of mathematical models used to design control strategies. Although the spread of infections through populations depends on more factors, found similarities suggest that spread may be similar in the Netherlands and Thailand

The burden of obesity in women of reproductive age and in pregnancy in a middle-income setting:A population based study from Jamaica

Obesity is rising globally and is associated with increased risk of adverse pregnancy outcomes. This study aims to investigate overweight and obesity and its consequences among Jamaican women of reproductive age, particularly development of diabetes, hypertension and the risk of maternal death.A national lifestyle survey (2007/8) of 1371 women of reproductive age provided data on the prevalence of high BMI, associated risk factors and co-morbidities. A national maternal mortality surveillance database (1998-2012) of 798 maternal deaths was used to investigate maternal deaths in obese women. Chi-squared and Fisher exact tests were used.High BMI (> = 25kg/m2) occurred in 63% of women aged between 15 and 49 years. It was associated with increasing age, high gravidity and parity, and full time employment (p<0.001). Of those with high BMI, 5.5% were diabetic, 19.3% hypertensive and 2.8% were both diabetic and hypertensive. Obesity was recorded in 10.5% of maternal deaths, with higher proportions of deaths due to hypertension in pregnancy (27.5%), circulatory/ cardiovascular disorders (13.0%), and diabetes (4.3%) compared to 21.9%, 6.9% and 2.6% respectively in non-obese women.This is one of a few studies from a middle-income setting to explore maternal burden of obesity during pregnancy, which contributes to improving the knowledge base, identifying the gaps in information and increasing awareness of the growing problem of maternal overweight and obesity. While survey diagnostic conditions require cautious interpretation of findings, it is clear that obesity and related medical conditions present a substantial public health problem for emerging LMICs like Jamaica. There is an urgent need for global consensus on routine measures of the burden and risk factors associated with obesity and development of culturally appropriate interventions

Impact of Emerging Antiviral Drug Resistance on Influenza Containment and Spread: Influence of Subclinical Infection and Strategic Use of a Stockpile Containing One or Two Drugs

BACKGROUND: Wide-scale use of antiviral agents in the event of an influenza pandemic is likely to promote the emergence of drug resistance, with potentially deleterious effects for outbreak control. We explored factors promoting resistance within a dynamic infection model, and considered ways in which one or two drugs might be distributed to delay the spread of resistant strains or mitigate their impact. METHODS AND FINDINGS: We have previously developed a novel deterministic model of influenza transmission that simulates treatment and targeted contact prophylaxis, using a limited stockpile of antiviral agents. This model was extended to incorporate subclinical infections, and the emergence of resistant virus strains under the selective pressure imposed by various uses of one or two antiviral agents. For a fixed clinical attack rate, R(0) rises with the proportion of subclinical infections thus reducing the number of infections amenable to treatment or prophylaxis. In consequence, outbreak control is more difficult, but emergence of drug resistance is relatively uncommon. Where an epidemic may be constrained by use of a single antiviral agent, strategies that combine treatment and prophylaxis are most effective at controlling transmission, at the cost of facilitating the spread of resistant viruses. If two drugs are available, using one drug for treatment and the other for prophylaxis is more effective at preventing propagation of mutant strains than either random allocation or drug cycling strategies. Our model is relatively straightforward, and of necessity makes a number of simplifying assumptions. Our results are, however, consistent with the wider body of work in this area and are able to place related research in context while extending the analysis of resistance emergence and optimal drug use within the constraints of a finite drug stockpile. CONCLUSIONS: Combined treatment and prophylaxis represents optimal use of antiviral agents to control transmission, at the cost of drug resistance. Where two drugs are available, allocating different drugs to cases and contacts is likely to be most effective at constraining resistance emergence in a pandemic scenario

A Biological Model for Influenza Transmission: Pandemic Planning Implications of Asymptomatic Infection and Immunity

Background: The clinical attack rate of influenza is influenced by prior immunity and mixing patterns in the host population, and also by the proportion of infections that are asymptomatic. This complexity makes it difficult to directly estimate R0 from the attack rate, contributing to uncertainty in epidemiological models to guide pandemic planning. We have modelled multiple wave outbreaks of influenza from different populations to allow for changing immunity and asymptomatic infection and to make inferences about R0. \ud \ud Data and Methods. On the island of Tristan da Cunha (TdC), 96% of residents reported illness during an H3N2 outbreak in 1971, compared with only 25% of RAF personnel in military camps during the 1918 H1N1 pandemic. Monte Carlo Markov Chain (MCMC) methods were used to estimate model parameter distributions. \ud \ud Findings. We estimated that most islanders on TdC were non-immune (susceptible) before the first wave, and that almost all exposures of susceptible persons caused symptoms. The median R0 of 6.4 (95% credibility interval 3.7–10.7) implied that most islanders were exposed twice, although only a minority became ill in the second wave because of temporary protection following the first wave. In contrast, only 51% of RAF personnel were susceptible before the first wave, and only 38% of exposed susceptibles reported symptoms. R0 in this population was also lower [2.9 (2.3–4.3)], suggesting reduced viral transmission in a partially immune population. \ud \ud Interpretation: Our model implies that the RAF population was partially protected before the summer pandemic wave of 1918, arguably because of prior exposure to interpandemic influenza. Without such protection, each symptomatic case of influenza would transmit to between 2 and 10 new cases, with incidence initially doubling every 1–2 days. Containment of a novel virus could be more difficult than hitherto supposed

Extracellular Matrix Aggregates from Differentiating Embryoid Bodies as a Scaffold to Support ESC Proliferation and Differentiation

Embryonic stem cells (ESCs) have emerged as potential cell sources for tissue engineering and regeneration owing to its virtually unlimited replicative capacity and the potential to differentiate into a variety of cell types. Current differentiation strategies primarily involve various growth factor/inducer/repressor concoctions with less emphasis on the substrate. Developing biomaterials to promote stem cell proliferation and differentiation could aid in the realization of this goal. Extracellular matrix (ECM) components are important physiological regulators, and can provide cues to direct ESC expansion and differentiation. ECM undergoes constant remodeling with surrounding cells to accommodate specific developmental event. In this study, using ESC derived aggregates called embryoid bodies (EB) as a model, we characterized the biological nature of ECM in EB after exposure to different treatments: spontaneously differentiated and retinoic acid treated (denoted as SPT and RA, respectively). Next, we extracted this treatment-specific ECM by detergent decellularization methods (Triton X-100, DOC and SDS are compared). The resulting EB ECM scaffolds were seeded with undifferentiated ESCs using a novel cell seeding strategy, and the behavior of ESCs was studied. Our results showed that the optimized protocol efficiently removes cells while retaining crucial ECM and biochemical components. Decellularized ECM from SPT EB gave rise to a more favorable microenvironment for promoting ESC attachment, proliferation, and early differentiation, compared to native EB and decellularized ECM from RA EB. These findings suggest that various treatment conditions allow the formulation of unique ESC-ECM derived scaffolds to enhance ESC bioactivities, including proliferation and differentiation for tissue regeneration applications. © 2013 Goh et al