205268986
The persistence of flood-borne pathogens on building surfaces under drying conditions.
Previous research into microbial persistence on material surfaces following flooding has produced a wide range of results due to differing experimental conditions, including the temperature and humidity conditions of the experimental material and/or surrounding air. However, investigations to identify and quantify these factors and their links to the hygrothermal properties of building materials and the transient environmental conditions are rarely reported. This paper examines the viability of bacterial species on drying material surfaces that have been saturated with water or synthetic sewage. Escherichia coli and Enterococcus faecalis were inoculated on brick, wood, or plaster and allowed to dry at the conditions intended to mimic the remediation environments commonly found in domestic dwellings following a flood event. The inactivation rates were compared between environmental conditions, water type and the material properties of the surfaces. Significant differences were found in the declines in E. coli according to water type, the surface relative humidity and air relative humidity and between drying rates for sewage floods. Simulations using hygrothermal software were performed to illustrate the wide variation in material drying rates under different scenarios, taking into account material size, wall composition, and ventilation. The significantly differing rates of microbial death on flooded building materials under different drying regimes suggest that building simulation models can be useful tools for predicting the level and duration of microbial contamination in buildings following a flood event. A better understanding of microbial survival on drying surfaces can be used to assess the health risks to occupants in flood affected properties.
16183837
The modifying effect of the building envelope on population exposure to PM2.5 from outdoor sources
A number of studies have estimated population exposure to PM2.5 by examining modeled or measured outdoor PM2.5 levels. However, few have taken into account the mediating effects of building characteristics on the ingress of PM2.5 from outdoor sources and its impact on population exposure in the indoor domestic environment. This study describes how building simulation can be used to determine the indoor concentration of outdoor-sourced pollution for different housing typologies and how the results can be mapped using building stock models and Geographical Information Systems software to demonstrate the modifying effect of dwellings on occupant exposure to PM2.5 across London. Building archetypes broadly representative of those in the Greater London Authority were simulated for pollution infiltration using EnergyPlus. In addition, the influence of occupant behavior on indoor levels of PM2.5 from outdoor sources was examined using a temperature-dependent window-opening scenario. Results demonstrate a range of I/O ratios of PM2.5, with detached and semi-detached dwellings most vulnerable to high levels of infiltration. When the results are mapped, central London shows lower I/O ratios of PM2.5 compared with outer London, an apparent inversion of exposure most likely caused by the prevalence of flats rather than detached or semi-detached properties.
12851840
Flood management: prediction of microbial contamination in large-scale floods in urban environments.
With a changing climate and increased urbanisation, the occurrence and the impact of flooding is expected to increase significantly. Floods can bring pathogens into homes and cause lingering damp and microbial growth in buildings, with the level of growth and persistence dependent on the volume and chemical and biological content of the flood water, the properties of the contaminating microbes, and the surrounding environmental conditions, including the restoration time and methods, the heat and moisture transport properties of the envelope design, and the ability of the construction material to sustain the microbial growth. The public health risk will depend on the interaction of these complex processes and the vulnerability and susceptibility of occupants in the affected areas. After the 2007 floods in the UK, the Pitt review noted that there is lack of relevant scientific evidence and consistency with regard to the management and treatment of flooded homes, which not only put the local population at risk but also caused unnecessary delays in the restoration effort. Understanding the drying behaviour of flooded buildings in the UK building stock under different scenarios, and the ability of microbial contaminants to grow, persist, and produce toxins within these buildings can help inform recovery efforts. To contribute to future flood management, this paper proposes the use of building simulations and biological models to predict the risk of microbial contamination in typical UK buildings. We review the state of the art with regard to biological contamination following flooding, relevant building simulation, simulation-linked microbial modelling, and current practical considerations in flood remediation. Using the city of London as an example, a methodology is proposed that uses GIS as a platform to integrate drying models and microbial risk models with the local building stock and flood models. The integrated tool will help local governments, health authorities, insurance companies and residents to better understand, prepare for and manage a large-scale flood in urban environments.
40285365
The polypeptides of influenza virus. IV. An analysis of nuclear accumulation.
Abstract Two of the three major structural polypeptides of influenza virus A Bel accumulate in the nucleus of cells that support the production of infectious virus as well as those in which the cycle is abortive. The migration is uninfluenced by multiplicity of infection, or by the addition of cycloheximide or actinomycin D. The polypeptide of the nucleocapsid migrates relatively slowly, and is found mainly in the nucleoplasm, whereas the other arginine-rich polypeptide, which is of lower molecular weight, migrates very rapidly and is found mainly in the nucleolus. Two of the three major polypeptides of the paramyxovirus, Newcastle disease virus, also accumulate in the nucleus.
44836362
A defective retrovirus particle (SE21Q1b) packages and reverse transcribes cellular RNA, utilizing tRNA-like primers.
Linial and co-workers described a quail cell line, SE21Q1b, transformed by a single provirus of Rous sarcoma virus that is defective in virus assembly, in as much as the virus particles produced, SE21, contain cellular rather than viral RNA. In other respects these particles are normal, and the amount of endogenous DNA synthesis by disrupted virus particles is comparable to that of normal virus. We now report that endogenous DNA synthesis by SE21 virions uses RNA primers of the same size as tRNA species and that about 17% of these are bound to polyadenylate-containing RNA templates. Previous studies have shown that with wild-type Rous sarcoma virus, DNA synthesis is exclusively initiated on a tRNATrp species base paired to a specific location on the viral RNA. In contrast, we interpreted our data with SE21 as evidence that many different tRNA-primed initiations occurred, that predominantly species other than tRNATrp were used, and that the base pairing between template and primer RNAs included significant nucleotide mismatching. A subpopulation of the DNA synthesized by SE21 virions from tRNA-like primers was both initiated and terminated at discrete locations. These species are therefore analogous to the strong-stop DNA synthesized by wild-type virus.
26391327
Reverse transcription of avian sarcoma virus RNA into DNA might involve copying of the tRNA primer.
Some of the double-stranded DNA products from the endogenous reaction of detergent-disrupted virions contain up to 18 3'-terminal nucleotides at a location consistent with their being transcribed from the tRNA primer.
13643640
Driving anxiety and fear in young older adults in New Zealand.
BACKGROUND
driving anxiety and fear can have a marked impact on mobility and independence, although there is no data on the prevalence of this problem, and specific information about the rate of driving anxiety and fear in older adults is unknown.


METHODS
the present study examines the prevalence of self-reported driving anxiety and fear in a sample of 2,491 adults aged 55-72 from a longitudinal survey of health and ageing in New Zealand.


RESULTS
most of the sample (90%) described themselves as drivers who drove daily or weekly. Around 70% of the sample reported no driving anxiety or fear, yet 17-20% endorsed a mild and 4-6% rated a moderate to severe level of driving anxiety and fear. Women reported higher levels of anxiety and fear about driving than men, but there were no age differences. Those who reported some level of driving anxiety engaged various alternative modes of transport, and a small number (2.4%) reported that their driving anxiety had affected their usual activities or work for at least a day in the previous month. Duration of driving anxiety was highly variable, from relatively recent onset to being present for much of some participants' lifetimes.


CONCLUSION
driving anxiety and fear may be a significant problem for some young older adults that is likely to affect their independence and mobility. Further research to clarify the content and nature of driving anxiety, pathways to driving anxiety and the effect of factors associated with ageing on driving anxiety is needed in order to better understand this experience for older adults and develop effective interventions.
205326823
Practitioner assessments of 'good enough' parenting: factorial survey.
AIM
The aim of this study was to measure health visitors' professional judgements on 'good enough' parenting and identify what factors and combinations of these are important when making such judgements.


BACKGROUND
The relationship between parenting and child health is unclear. Whilst agreement exists that 'good enough' parenting requires boundary setting, consistency and putting the child's needs first, attempting to define 'good enough' parenting in precise terms is complex. When faced with a complex situation, practitioners rely on relatively few factors to form judgements.


DESIGN
Factorial survey methods were employed using vignette techniques.


METHODS
Vignettes were constructed using previous research on those variables, which may influence nurses' judgements, for example, accommodation and child dentition. The level of factors was randomly varied. Two thousand vignettes were administered to a sample of 200 health visitors in two Health Boards who then made a judgement about this scenario.


ANALYSIS
Data were analysed through multiple regression with dummy variables and one-way analysis of variance. Regression equations for both good enough mothering and good enough parenting are reported.


RESULTS
The models used are significant predictors of parenting and mothering. Significant predictors on health visitor judgements' were boundary setting in sleep behaviours, type of housing inhabited and health behaviours. Although parenting and mothering are often conflated, health visitors appear to separate these aspects when making judgements based on type of housing.


CONCLUSIONS
Most professionals can articulate what makes a 'good' parent, equally they may have strong views regarding what constitutes 'poor' parenting. The difficulty is in determining when parenting is 'good enough' to provide a child with a nurturing environment.


RELEVANCE TO CLINICAL PRACTICE
This study suggests that practitioners move their thresholds of what is 'good enough' depending on a narrow range of factors. Awareness of the factors, which influence individuals' judgements is important in safeguarding children.