Simulating star formation in molecular cloud cores IV. The role of turbulence and thermodynamics

We perform SPH simulations of the collapse and fragmentation of low-mass cores having different initial levels of turbulence (alpha_turb=0.05,0.10,0.25). We use a new treatment of the energy equation which captures the transport of cooling radiation against opacity due to both dust and gas (including the effects of dust sublimation, molecules, and H^- ions). We also perform comparison simulations using a standard barotropic equation of state. We find that -- when compared with the barotropic equation of state -- our more realistic treatment of the energy equation results in more protostellar objects being formed, and a higher proportion of brown dwarfs; the multiplicity frequency is essentially unchanged, but the multiple systems tend to have shorter periods (by a factor ~3), higher eccentricities, and higher mass ratios. The reason for this is that small fragments are able to cool more effectively with the new treatment, as compared with the barotropic equation of state. We find that the process of fragmentation is often bimodal. The first protostar to form is usually, at the end, the most massive, i.e. the primary. However, frequently a disc-like structure subsequently forms round this primary, and then, once it has accumulated sufficient mass, quickly fragments to produce several secondaries. We believe that this delayed fragmentation of a disc-like structure is likely to be an important source of very low-mass hydrogen-burning stars and brown dwarfs.Comment: 14 pages, 8 figures. Accepted for publication by A&

Irish County Incomes in 1960. ESRI General Research Series Paper No. 16, September 1963

This paper owes its inception to a problem which the Taoiseach (Prime Minister), Mr. Se~n F. Lemass, T.D., at the Opening Ceremony on 6 June, 196I, asked the Institute to examine, in the following terms:-- "The Minister for Finance has already raised the questions whether the present system is adequate or appropriate to deal with the increasing activities of local bodies or whether a more rational or more effective system could be devised. There is a situation developing in local authority operations, and their financing, which requires consideration. Investigations, under the auspices of the Institute, of certain aspects, including the economic aspects, of the incidence of local taxation covering such matters as the effect of the local rate charge on enterprise and development, and the possibilities of providing Local Authorities with new sources of income, will provide some basic material which will be invaluable in the review of local finance which the Minister for Local Government intends to undertake"

Irish County Incomes in 1960. ESRI General Research Series Paper No. 16, September 1963

This paper owes its inception to a problem which the Taoiseach (Prime Minister), Mr. Se~n F. Lemass, T.D., at the Opening Ceremony on 6 June, 196I, asked the Institute to examine, in the following terms:-- "The Minister for Finance has already raised the questions whether the present system is adequate or appropriate to deal with the increasing activities of local bodies or whether a more rational or more effective system could be devised. There is a situation developing in local authority operations, and their financing, which requires consideration. Investigations, under the auspices of the Institute, of certain aspects, including the economic aspects, of the incidence of local taxation covering such matters as the effect of the local rate charge on enterprise and development, and the possibilities of providing Local Authorities with new sources of income, will provide some basic material which will be invaluable in the review of local finance which the Minister for Local Government intends to undertake"

The current situation and policies of the New Zealand cereals sector

In New Zealand's agricultural sector, the dominant position of pastoral enterprises has resulted in relatively little importance being attached to the production of arable crops. At times of strong demand and remunerative prices for milk, sheepmeat, beef and wool, the comparative advantage of New Zealand producers of these products over those in other countries has justified the general lack of any strong concern for the development of the arable sector. When, however, the market for livestock and livestock products is weak, the further expansion of other farm products, including cereals, becomes a much more attractive proposition. It is not perhaps always appreciated that the proportion of total agricultural land in New Zealand devoted to cereal production is very small. Over the past decade, the area under cereals has fluctuated around 200,000 ha with the trend over these years being slowly downwards, from an average of 210,000 ha during the five year period 1973-77 to an average of 190,000 over the period 1979-83 (although the 1983-84 out turn has shown a sharp reversal of this trend). This area under cereals represents less than one per cent of the total agricultural land in the country, although the quality of the land involved is above that for the country as a whole. Cereals account for less than ten per cent of the proportion of the 2.5m hectares of land of high actual or potential value for the production of food. This paper is concerned with the production and utilisation of the four cereals produced commercially in New Zealand - wheat, barley, oats and maize, and the official policies which influence them

Feminist Art Activisms and Artivisms - 2 July 2018, Middlesex University

This event was organised by Katy Deepwell for the Create/Feminisms research cluster in the Visual Arts Department, Faculty of Arts and Creative Industries, Middlesex University

ATRA mechanically reprograms pancreatic stellate cells to suppress matrix remodelling and inhibit cancer cell invasion

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy with a dismal survival rate. Persistent activation of pancreatic stellate cells (PSCs) can perturb the biomechanical homoeostasis of the tumour microenvironment to favour cancer cell invasion. Here we report that ATRA, an active metabolite of vitamin A, restores mechanical quiescence in PSCs via a mechanism involving a retinoic acid receptor beta (RAR-β)-dependent downregulation of actomyosin (MLC-2) contractility. We show that ATRA reduces the ability of PSCs to generate high traction forces and adapt to extracellular mechanical cues (mechanosensing), as well as suppresses force-mediated extracellular matrix remodelling to inhibit local cancer cell invasion in 3D organotypic models. Our findings implicate a RAR-β/MLC-2 pathway in peritumoural stromal remodelling and mechanosensory-driven activation of PSCs, and further suggest that mechanical reprogramming of PSCs with retinoic acid derivatives might be a viable alternative to stromal ablation strategies for the treatment of PDAC

Core-Shell Electrospun Polycrystalline ZnO Nanofibers for Ultra-Sensitive NO2 Gas Sensing.

This Research Article discusses the growth of polycrystalline, self-supporting ZnO nanofibers, which can detect nitrogen dioxide (NO2) gas down to 1 part per billion (ppb), one of the smallest detection limits reported for NO2 using ZnO. A new and innovative method has been developed for growing polycrystalline ZnO nanofibers. These nanofibers have been created using core-shell electrospinning of inorganic metal precursor zinc neodecanoate, where growth occurs at the core of the nanofibers. This process produces contamination-free, self-supporting, polycrystalline ZnO nanofibers of an average diameter and grain size 50 and 8 nm, respectively, which are ideal for gas sensing applications. This process opens up an exciting opportunity for creating nanofibers from a variety of metal oxides, facilitating many new applications especially in the areas of sensors and wearable technologies.Llodys Register foundatio

The organisational and human resource challenges facing primary care trusts : protocol of a multiple case study

BACKGROUND: The study is designed to assess the organisational and human resource challenges faced by Primary Care Trusts (PCTs). Its objectives are to: specify the organisational and human resources challenges faced by PCTs in fulfilling the roles envisaged in government and local policy; examine how PCTs are addressing these challenges, in particular, to describe the organisational forms they have adopted, and the OD/HR strategies and initiatives they have planned or in place; assess how effective these structures, strategies and initiatives have been in enabling the PCTs to meet the organisational and human resources challenges they face; identify the factors, both internal to the PCT and in the wider health community, which have contributed to the success or failure of different structures, strategies and initiatives. METHODS: The study will be undertaken in three stages. In Stage 1 the key literature on public sector and NHS organisational development and human resources management will be reviewed, and discussions will be held with key researchers and policy makers working in this area. Stage 2 will focus on detailed case studies in six PCTs designed to examine the organisational and human resources challenges they face. Data will be collected using semi-structured interviews, group discussion, site visits, observation of key meetings and examination of local documentation. The findings from the case study PCTs will be cross checked with a Reference Group of up to 20 other PCG/Ts, and key officers working in organisational development or primary care at local, regional and national level. In Stage 3 analysis of findings from the preparatory work, the case studies and the feedback from the Reference Group will be used to identify practical lessons for PCTs, key messages for policy makers, and contributions to further theoretical development

Will the introduction of non-invasive prenatal diagnostic testing erode informed choices? An experimental study of health care professionals

Objective. Informed choice is a fundamental concept within prenatal care. The present study assessed the extent to which the introduction of non-invasive prenatal diagnosis (NIPD) of Down's syndrome may undermine the process of making informed choices to undergo prenatal testing or screening for Down's syndrome by altering the quality and quantity of pre-test counselling. Methods. 231 obstetricians and midwives were randomly allocated one of three vignettes, each describing a different type of test: (a) invasive prenatal diagnosis (IPD), (b) non-invasive prenatal diagnosis (NIPD) or (c) Down's syndrome screening (DSS). Participants were then asked to complete a questionnaire assessing (1) the information considered important to communicate to women, (2) whether test offer and uptake should take place on different days, and (3) whether signed consent forms should be obtained prior to testing. Results. Across the three test types, five out of the seven presented topics were considered equally important to communicate, including the information that testing is the woman's choice. Compared with participants receiving the IPD vignette, those receiving the NIPD and DSS vignettes were less likely to report that counselling and testing should occur on different days (IPD 94.7% versus 74.1% and 73.9% for NIPD and DSS respectively, p = .001) and that written consent was a necessity (IPD 96.1% versus 68.3% and 75.4% for NIPD and DSS respectively, p < .001). Conclusion. This study provides the first empirical evidence to demonstrate that practitioners may view the consent process for NIPD differently to IPD. There is potential for the introduction of NIPD to undermine women making informed choices in the context of prenatal diagnostic testing for conditions like DS. Practice implications. Given the importance of informed choice in reproductive decision-making, implementation of any programme based on NIPD should be designed to facilitate this. Keywords: Informed choice; Prenatal; Down's syndrome; Non-invasive testingThis article was written by Dr Ainsley Newson during the time of her employment with the University of Bristol, UK (2006-2012). Self-archived in the Sydney eScholarship Repository with permission of Bristol University, Sept 2014