An analytical solution for solid stresses in a silo with an inner tube

This paper presents an analytical solution for the solid stresses in a silo with an internal tube. The research was conducted to support the design of a group of full scale silos with large inner concrete tubes. The silos were blasted and formed out of solid rock underground for storing iron ore pellets. Each of these silos is 40m in diameter and has a 10m diameter concrete tube with five levels of openings constructed at the centre of each rock silo. A large scale model was constructed to investigate the stress regime for the stored pellets and to evaluate the solids flow pattern and the loading on the concrete tube. This paper focuses on the development of an analytical solution for stresses in the iron ore pellets in the silo and the effect of the central tube on the stress regimes. The solution is verified using finite element analysis before being applied to analyse stresses in the solid in the full scale silo and the effect of the size of the tube.

Treatment of retinopathy of prematurity in Northern Ireland, 2000-2011: a population-based study

Purpose To evaluate the incidence of treatment-requiring retinopathy of prematurity (ROP) over a 12-year-period in Northern Ireland. Methods The medical records of all infants treated for ROP from January 2000 to December 2011were retrospectively reviewed and cross-referenced with the Neonatal Intensive Care Outcomes Research and Evaluation (NICORE) database. Results The Northern Ireland population data showed an increase in the number of live births from 2000 to 2011. The proportion of babies born with a birth weight <1501 g and/or <32 weeks’ gestational age remained constant (χ2 trend = 3.220, P = 0.0727), although the proportion of these babies who died prior to 42 weeks’ gestation decreased from 2000 to 2011 (P = 0.0196 using χ2 for trend = 5.445; P = 0.0354 using χ2 = 20.809). The prevalence of treatment-requiring ROP in these infants increased from 1.05% in 2000 to 5.78% in 2011 (P < 0.001 using χ2 trend = 16.309; P < 0.001 using χ2 = 31.378). Conclusions The present population-based study highlights that the incidence of treatment- requiring ROP is increasing in Northern Ireland. The increasing number of infants requiring treatment will need to be taken into consideration in the commissioning process for ROP services in Northern Ireland.

Nuclear LYRIC/AEG-1 interacts with PLZF and relieves PLZF-mediated repression

LYRIC/AEG-1 and its altered expression have been linked to carcinogenesis in prostate, brain and melanoma as well as promoting chemoresistance and metastasis in breast cancer. LYRIC/AEG-1 function remains unclear, although LYRIC/AEG-1 is activated by oncogenic HA-RAS, through binding of c-myc to its promoter, which in turn regulates the key components of the PI3-kinase and nuclear factor-kappaB pathways. We have identified the transcriptional repressor PLZF as an interacting protein of LYRIC/AEG through a yeast two-hybrid screen. PLZF regulates the expression of genes involved in cell growth and apoptosis including c-myc. Coexpression of LYRIC/AEG-1 with PLZF leads to a reduction in PLZF-mediated repression by reducing PLZF binding to promoters. We have confirmed that nuclear LYRIC/AEG-1 and PLZF interact in mammalian cells via the N- and C termini of LYRIC/AEG-1 and a region C terminal to the RD2 domain of PLZF. Both proteins colocalize to nuclear bodies containing histone deacetylases, which are known to promote PLZF-mediated repression. Our data suggest one mechanism for cells with altered LYRIC/AEG-1 expression to evade apoptosis and increase cell growth during tumourigenesis through the regulation of PLZF repression.

The impact of organisational factors and government policy on psychiatric nurses family focused practice with parents who have mental illness, their dependent children and families in Ireland

Government policy and organizational factors influence family focused practice in adult mental health services. However, how these aspects shape psychiatric nurses’ practice with parents who have mental illness, their dependent children and families is less well understood. Drawing on the findings of a qualitative study, this article explores the way in which Irish policy and organizational factors might influence psychiatric nurses’ family focused practice, and whether (and how) family focused practice might be further promoted. A purposive sample of 14 psychiatric nurses from eight mental health services completed semi-structured interviews in 2013. The analysis was inductive and presented as thematic networks. Both groups described how policies and organizational culture enabled and/or hindered family focused practice, with differences between community and acute participants seen. The need to develop national and international policies along with practices to embed information and support regarding parenting into ongoing care is implicated in this study.

Scotland’s Curriculum for Excellence: a defence of autonomy and personhood.

Curriculum for Excellence, Scotland’s 3-18 curriculum, has been described as ‘the most significant curricular change in Scotland for a generation’ (McAra, Broadley and McLauchlan, 2013:223). The purpose of the curriculum is ‘encapsulated’ in four capacities in order that learners become i) successful learners, ii) confident individuals, iii) responsible citizens, and iv) effective contributors. With particular reference to these capacities, we explore the principle of autonomy as it pertains to both individual and collective flourishing seeking to disarm commonplace criticisms of autonomy by arguing that it might be put to work in CfE as a potentially multi-dimensional, context-sensitive concept that is relational as well as individual. We conclude that the four capacities lend themselves to re-consideration and re-mapping in pursuit of autonomy and flourishing premised on the principles of liberal personhood.

Breaking and Entering: Examining the role of stress and aerial exposure in predator-prey relationships between the common shore crab (Carcinus maenas) and cultivated blue mussels (Mytilus edulis).

During benthic cultivation Mytilus edulis (blue mussels) are subject to predation pressure from a number of predators including Carcinus maenas (shore crabs). This predator can be responsible for substantial losses of mussels from the fishery and a full understanding of the predator–prey relationship between M. edulis and C. maenas is required to ensure attempts that reduce predatory pressure and subsequent commercial loss are successful. Whilst much work has examined the prey–predator size relationships between C. maenas and M. edulis, far less research has investigated how stress, such as periods of extended aerial exposure, may affect these relationships. We tested whether profit in terms of calories gained by crabs consuming mussels stressed by aerial exposure for 48 h differed from that of mussels at ambient conditions and whether being stressed affected the mussel's likelihood of predation. We also tested whether the size relationship between predators and their prey differed when mussels were stressed. We found that the profitability of prey (calories gained per second of handling time) did not vary between stressed and unstressed mussels. Handling times for stressed and unstressed mussels were similar, even when crabs were presented with mussels of the maximum size that they are able to consume. Small crabs were more likely to reject a mussel of preferred size if it was unstressed, suggesting that crabs may be able to assess that these mussels would require extra effort to break into and consume. Our findings suggest that the predator–prey relationship between mussels and crabs is not altered when mussels are stressed. C. maenas remains a voracious predator and regardless of the condition of mussels laid on commercial beds there is a need to control this predator in attempt to reduce losses in the benthic fishery.

Quantitative regulation of FLC via coordinated transcriptional initiation and elongation

The basis of quantitative regulation of gene expression is still poorly understood. In Arabidopsis thaliana, quantitative variation in expression of FLOWERING LOCUS C (FLC) influences the timing of flowering. In ambient temperatures, FLC expression is quantitatively modulated by a chromatin silencing mechanism involving alternative polyadenylation of antisense transcripts. Investigation of this mechanism unexpectedly showed that RNA polymerase II (Pol II) occupancy changes at FLC did not reflect RNA fold changes. Mathematical modeling of these transcriptional dynamics predicted a tight coordination of transcriptional initiation and elongation. This prediction was validated by detailed measurements of total and chromatin-bound FLC intronic RNA, a methodology appropriate for analyzing elongation rate changes in a range of organisms. Transcription initiation was found to vary ∼ 25-fold with elongation rate varying ∼ 8- to 12-fold. Premature sense transcript termination contributed very little to expression differences. This quantitative variation in transcription was coincident with variation in H3K36me3 and H3K4me2 over the FLC gene body. We propose different chromatin states coordinately influence transcriptional initiation and elongation rates and that this coordination is likely to be a general feature of quantitative gene regulation in a chromatin context.

Studying Gender in Conference Talks -- data from the 223rd meeting of the American Astronomical Society

We present a study on the gender balance, in speakers and attendees, at the recent major astronomical conference, the American Astronomical Society meeting 223, in Washington, DC. We conducted an informal survey, yielding over 300 responses by volunteers at the meeting. Each response included gender data about a single talk given at the meeting, recording the gender of the speaker and all question-askers. In total, 225 individual AAS talks were sampled. We analyze basic statistical properties of this sample. We find that the gender ratio of the speakers closely matched the gender ratio of the conference attendees. The audience asked an average of 2.8 questions per talk. Talks given by women had a slightly higher number of questions asked (3.2$\pm$0.2) than talks given by men (2.6$\pm$0.1). The most significant result from this study is that while the gender ratio of speakers very closely mirrors that of conference attendees, women are under-represented in the question-asker category. We interpret this to be an age-effect, as senior scientists may be more likely to ask questions, and are more commonly men. A strong dependence on the gender of session chairs is found, whereby women ask disproportionately fewer questions in sessions chaired by men. While our results point to laudable progress in gender-balanced speaker selection, we believe future surveys of this kind would help ensure that collaboration at such meetings is as inclusive as possible.

Green Space Attachment and Health: A Comparative Study in Two Urban Neighborhoods

The positive relationships between urban green space and health have been well documented. Little is known, however, about the role of residents’ emotional attachment to local green spaces in these relationships, and how attachment to green spaces and health may be promoted by the availability of accessible and usable green spaces. The present research aimed to examine the links between self-reported health, attachment to green space, and the availability of accessible and usable green spaces. Data were collected via paper-mailed surveys in two neighborhoods (n = 223) of a medium-sized Dutch city in the Netherlands. These neighborhoods differ in the perceived and objectively measured accessibility and usability of green spaces, but are matched in the physically available amount of urban green space, as well as in demographic and socio-economic status, and housing conditions. Four dimensions of green space attachment were identified through confirmatory factor analysis: place dependence, affective attachment, place identity and social bonding. The results show greater attachment to local green space and better self-reported mental health in the neighborhood with higher availability of accessible and usable green spaces. The two neighborhoods did not differ, however, in physical and general health. Structural Equation Modelling confirmed the neighborhood differences in green space attachment and mental health, and also revealed a positive path from green space attachment to mental health. These findings convey the message that we should make green places, instead of green spaces.

Cataract surgery and subtype in a defined, older population: the SEECAT Project

AIM:

To describe the distribution of cataract subtypes present before surgery among a defined population of older, bilaterally pseudophakic individuals.

METHODS:

This was a cohort study of bilaterally pseudophakic individuals participating in the Salisbury Eye Evaluation (SEE), and their locally resident siblings. Subjects underwent slit lamp and retroillumination photography and grading using the Wilmer Cataract Grading System. For all individuals determined to be bilaterally pseudophakic, an attempt was made to determine for each eye the type(s) of cataract present before surgery, based on previous SEE photographs (for SEE participants) and/or medical records obtained from the operating ophthalmologist (for both SEE participants and their siblings).

RESULTS:

The mean age of 223 participants providing data in this study was 78.7 (SD 5.2) years, 19.3% of subjects were black and 60.1% female. The most common surgically removed cataract subtype in this population was pure nuclear (43.5%), followed by nuclear combined with posterior subcapsular cataract (PSC) (20.6%), and nuclear combined with cortical (13.9%); less common types were pure cortical (4.9%), pure PSC (4.5%), and PSC combined with cortical (2.7%). Factors such as sex and source of lens data (study photograph versus clinical record) did not significantly affect the distribution of lens opacity types, while PSC was significantly (p = 0.01) more common among younger people and nuclear cataract was significantly (p = 0.001) more common among white compared to black people.

CONCLUSION:

Epidemiological studies have suggested that the different subtypes of cataract are associated with different risk factors. As studies begin to identify new prevention strategies for cataract, it would appear likely that different strategies will be efficacious against different types of cataract. In this setting, it will be helpful to know which cataract types are most frequently associated with surgery. Among this older, majority white population, nuclear cataract showed a clear predominance among individuals having undergone surgery in both eyes. This may be contrasted with both clinic and population based studies of younger people, which have generally found PSC cataract to predominate.