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Associations between predictors of children’s dietary intake and socioeconomic position : a systematic review of the literature
No full textSocioeconomically disadvantaged children are at higher risk of consuming poor diets, in particular less fruits and vegetables and more non-core foods and sweetened beverages. Currently the drivers of socioeconomically related differences in children’s dietary intake are not well understood. This systematic review explored whether dietary predictors vary for children of different socioeconomic circumstances. Seven databases and reference lists of included material were searched for studies investigating predictors of 9–13-year-old children’s diet in relation to socioeconomic position. Individual- and population-based cross-sectional, cohort and epidemiological studies published in English and conducted in developed countries were included. Twenty-eight studies were included in this review; most were conducted in Europe (n = 12) or North America (n = 10). The most frequently used indicators of socioeconomic position were parent education and occupation. Predictors of children’s dietary intake varied among children of different socioeconomic circumstances. Socioeconomic position was consistently associated with children’s nutrition knowledge, parent modelling, home food availability and accessibility. Indeterminate associations with socioeconomic position were observed for parent feeding practices and food environment near school. Differences in the determinants of eating between socioeconomic groups provide a better understanding of the drivers of socioeconomic disparities in dietary intake, and how to develop targeted intervention strategies.
Challenges of NextGen technologies for coordinated decision making and the exchange of information between pilots and controllers
No full textIntroduction: This paper presents two studies that explore the implications of NextGen technologies for pilot/controller information exchange and coordinated decision making. Method: In Study 1 five participative focus groups were conducted with human factors experts. In Study 2 fifteen interviews were conducted with air traffic controllers. Both studies employed a thematic analysis. Results and Discussion: Results from Study 1 suggest that changes to pilot and controller information acquisition will alter rather than reduce breakdowns in coordinated decision making. Study 2 identified some basic issues in information exchange with NextGen technologies and suggests that some important non-operational information will be lost. Conclusion: The two studies highlight some important challenges that need to be carefully considered as the NextGen technologies move towards maturity.
Low temperature thermal dependent Filgrastim adsorption behavior detected with ToF-SIMS
No full textTime-of-flight secondary ion mass spectrometry (ToF-SIMS) detected changes in Filgrastim (granulocyte colony stimulating growth factor, G-CSF) adsorption behavior at a solid interface when exposed to temperatures as low as 35 °C, i.e., before thermal denaturation, was detected by circular dichroism (CD) or dynamic light scattering (DLS). Biopharmaceuticals rely on maintaining sufficient conformation to impart correct biological function in vivo. Stability of such molecules is critical during synthesis, storage, transport, and administration. CD analysis indicated loss of structure at temperatures greater than 60 °C, while DLS detected aggregation at 42 °C. Furthermore, we demonstrate the nature of G-CSF interaction with a surface was altered rapidly and at relatively low temperatures. Specifically, after 10 min thermal treatment, changes in adsorption behavior occurred at 35 °C indicated by principal component analysis of spectra as primarily due to increasing yields of methionine fragments. This was likely to be due to either altering the preferential protein orientation upon adsorption or greater denaturation exposing the hydrophobic core. This investigation demonstrates the sensitivity of ToF-SIMS in studying biopharmaceutical adsorption and conformational change and can assist with studies into promoting their stability.
Computational finance: a very long walk down Wall Street
No full textProponents of the random walk have attempted to show that there seems to be a resemblance between a plot of random price in a time-series and the actual stock market. This paper takes a step further, by simulating such a plot over a period of more than 220,000,000 years and to determine whether among the very long time sequence of values if any sequence resembles that of Dow Jones Industrial Average (DJIA). The experimental simulation presented in this paper is the first to visualize the Random Walk Hypothesis with DJIA actual drift vis-à-vis the DJIA actual outcome. Existing papers on Random Walk Hypothesis attempted to show that a randomly simulated price-time plot seems to resemble the price-time plot of the stock market. In contrast, this paper shows that despite numerous attempts to produce a sequence using randomly generated numbers over more than 220,000,000 of human years, there is no possibility that random walk plots resemble the DJIA.
Interaction of platelets with poly(vinylidene fluoride-co-hexafluoropropylene) electrospun surfaces
No full textPlatelets are the major contributors in the process of thrombosis and in the failure of biomedical implants. A number of factors influence the platelet interaction with foreign surfaces such as surface morphology, surface chemistry, and adsorbed proteins. This study examined the effect of surface topography and chemistry of pristine and fibrinogen-adsorbed solvent cast (SC) and electrospun (ES) samples of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) on platelet adhesion, activation, and aggregation. Qualitative and quantitative studies of fibrinogen adsorption were performed using time-of-flight secondary ion mass spectrometry (ToF-SIMS), while SEM, aggregometry, and liquid scintillation analyses were performed to evaluate platelet adhesion, aggregation, and serotonin release. While little or no platelet adhesion was observed on pristine ES surfaces, considerable adhesion, and measurable aggregation and serotonin release were observed on pristine SC surfaces. Notably, increased adhesion of platelets was observed following fibrinogen adsorption on SC surface with considerable aggregation and serotonin release compared with ES samples, where limited aggregation and platelet adhesion was observed. A further comparison of platelet adhesion, aggregation, and serotonin release was performed with plasma-adsorbed SC and ES surfaces. SC surfaces showed enhanced platelet adhesion, aggregation, and serotonin release compared to ES surfaces. This study shows that the morphology of samples plays a critical role on the biocompatibility of samples by altering the adsorption and adhesion of biomolecules and cells. The low level of adhesion, low aggregation, and serotonin release of platelets, even in the presence of fibrinogen and plasma-derived proteins, suggested that ES samples have the least thrombogenicity.
Comparative sorption of Pb and Cd by biochars and its implication for metal immobilization in soils
No full textBiochar has great potential as a soil amendment to immobilize heavy metals, thereby reducing their bioavailability. In this study, biochars derived from chicken manure and green waste were compared with commercial activated carbon (AC) and laboratory produced black carbon (BC) for the sorption of Pb and Cd. Sorption kinetics and equilibrium sorption isotherms for Pb and Cd were obtained for the char materials and the data were fitted to kinetic and sorption isotherm models.. Chicken manure-derived biochar (CM) showed the highest sorption capacity for both Pb and Cd, and the Pb sorption by biochars was higher than the Cd sorption because of the precipitation of Pb with various ions released from the biochars such as carbonate, phosphate, and sulfate. The sorption data for both Pb and Cd were better represented by the pseudo-second order kinetic model than the pseudo-first order kinetic model, which indicates chemical sorption between biochar and metals. For the isotherm studies, char materials was mixed with various amount of Pb or Cd solutions and the remaining metal concentration was measured. The equilibrium sorption data followed a Langmuir isotherm with a maximum sorption capacity of 6.8–11 and 1.7–8.0 mg/g by biochars for Pb and Cd, respectively. Furthermore, CM immobilized Pb and Cd up to 93.5 and 88.4 %, respectively, while BC was not effective in the immobilization of Pb in soil. Overall, the sorption experiments in solution and the immobilization experiment in soil showed that biochars are more effective than AC in the sorption of Pb and Cd, and that they have the potential to be used as a soil amendment to remediate metal-contaminated soil.
Investigating psychological factors of behavioural intention of urban residents in South Australia to use treated stormwater for non-potable purposes
No full textThis paper reports on the intentions of urban residents in two South Australian Local Government Areas (LGAs) (council areas) to use stormwater treated through a managed aquifer recharge process for various potential non-potable uses. Data were collected through an online survey of the residents in these LGAs. The key finding is that, in common with recycled sewage water, the intention to use treated stormwater was lower for uses having closer contact with people. A hypothesized model consisting of possible factors influencing the intention to use treated stormwater was developed based on the contemporary literature relating to usage of treated sewage water. Greater trust in the local water authority was shown to be associated directly and closely with a lower perceived health risk. A positive attitude by respondents to the use of treated stormwater (as an aspect of a sustainable future) was found to be more likely to result in an intention to use the treated stormwater for non-potable purposes. Respondents' perceived health risk, emotions and environmental concerns all had significant associations with their attitudes to using stormwater but were not associated with their intention to use it.
Conducting discrete choice experiments to inform healthcare decision making : a user's guide
No full textWe conclude that if appropriately designed, implemented, analysed and interpreted, DCEs offer several advantages in the health sector, the most important of which is that they provide rich data sources for economic evaluation and decision making, allowing investigation of many types of questions, some of which otherwise would be intractable analytically. Thus, they offer viable alternatives and complements to existing methods of valuation and preference elicitation.