21,576 research outputs found
Level crossing in the three-body problem for strongly interacting fermions in a harmonic trap
We present a solution of the three-fermion problem in a harmonic potential
across a Feshbach resonance. We compare the spectrum with that of the two-body
problem and show that it is energetically unfavorable for the three fermions to
occupy one lattice site rather than two. We also demonstrate the existence of
an energy level crossing in the ground state with a symmetry change of its wave
function, suggesting the possibility of a phase transition for the
corresponding many-body case.Comment: 5 pages, 6 figures, typos corrected, references adde
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Teaching schools evaluation. Research Brief
This Research Brief reports the findings from a two-year study (2013-15) in to the work of teaching schools and their alliances commissioned by the National College for Teaching and Leadership (NCTL). The broad aim of the study was to investigate the effectiveness and impact of teaching schools on improvement, and identify the quality and scope of external support that are required to enhance these . This was achieved through combining qualitative and quantitative data collection and analysis derived from three research activities: case studies of 26 teaching schools alliances (TSAs), a national survey of the first three cohorts of 345 TSAs, and secondary research and analysis of national performance and inspection results
Internal Migration and Regional Population Dynamics in Europe: Estonia Case Study
Estonia has experienced a long-lasting and strong influence of international migration on regional population growth. Post-war immigrants account for about 36 per cent of the total population, and are concentrated in larger cities of Northern Estonia. Regionally, the relative proportions of the native-born and immigrant origin sub-populations are important for the understanding of population change and internal migration flows in the 1980-1990s.
In Estonia, the quality of migration data requires careful assessment. The preservation of Soviet-type record-keeping has reduced data quality in the 1990s, already low, and use of the data should keep data quality problems in mind. Otherwise, false conclusions can be reached.
To describe internal migration patterns, it has proved technically feasible and very useful to disaggregate the county population into rural and urban components, and correspondingly, the migration flows into four directions (urban-urban, urban-rural, rural-urban and rural-rural).
During the 1980s the pattern of population growth and internal migration has changed in Estonia. Reflecting the turnaround in long-term population processes, migration development reached the advanced stage with more or less regionally balanced in- and out-migration flows and decreasing importance of net migration. Accordingly, to understand current trends and patterns, explanations must be sought from the 1980s which has served a starting point for the present trends rather than from the period of economic transition in the 1990s.
As a part of the turnaround, the century-long persistent rural depopulation has come to an end and the moderate growth has started reflecting natural population increase as well as deurbanization. In the 1980s two developments have occurred in parallel: migratory increase of rural population led by a deurbanizing native-born population, and continued urban population growth as a result of the population momentum of pre-transition immigrants. In future decades, the urban deconcentration will probably be the underlying trend in Estonia. In Estonia, noticeable proportion of territory and population is located in islands. However, the island population does not show any systematic difference in the type of internal migration. Particularly, the depopulation of island populations, observed in several comparable European cases, is not occurring.
Each life-course stage was found to have its specific migration pattern, more stable than the pattern for the total population. In many cases the changes of internal migration are determined by the change in the proportion of population in different life-course stages. Additionally, the life-course approach has been useful in demonstrating the features of the present Estonian internal migration pattern which appear closer to the countries of comparable in demographic development, more or less regardless of the significant differences in the level of economic development. Among life-course groups, in Estonia the older working age population was characterized by the strongest deurbanization intensities in 1995. The same group has also undergone the largest modification of migration pattern during the economic transition (1987-1995)
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GRIDCC: Real-time workflow system
The Grid is a concept which allows the sharing of resources between distributed communities, allowing each to progress towards potentially different goals. As adoption of the Grid increases so are the activities that people wish to conduct through it. The GRIDCC project is a European Union funded project addressing the issues of integrating instruments into the Grid. This increases the requirement of workflows and Quality of Service upon these workflows as many of these instruments have real-time requirements. In this paper we present the workflow management service within the GRIDCC project which is tasked with optimising the workflows and ensuring that they meet the pre-defined QoS requirements specified upon them
Contemporary debates on institutions: governance, governmentality and power
Institutions, at state and local level, have been perceived as a mechanism of supporting the vulnerable within society. The processes of globalisation within an economic, political and social context have played a fundamental role in institutions. The 'State' that administers institutions has experienced involvement and adjustment by central government's policy of privatisation and deregulation. The aim of this paper is to critically explore the current debates on institutions within British society. We frame the debates within Foucault's notion of 'governmentality', which highlights how government provides governance of 'action at a distance' in order to detract blame from government and its policies and place this blame onto individuals and communities themselves (1978, p. 33)
The LATDYN user's manual
The LATDYN User's Manual presents the capabilities and instructions for the LATDYN (Large Angle Transient DYNamics) computer program. The LATDYN program is a tool for analyzing the controlled or uncontrolled dynamic transient behavior of interconnected deformable multi-body systems which can undergo large angular motions of each body relative other bodies. The program accommodates large structural deformation as well as large rigid body rotations and is applicable, but not limited to, the following areas: (1) development of large flexible space structures; (2) slewing of large space structure components; (3) mechanisms with rigid or elastic components; and (4) robotic manipulations of beam members. Presently the program is limited to two dimensional problems, but in many cases, three dimensional problems can be exactly or approximately reduced to two dimensions. The program uses convected finite elements to affect the large angular motions involved in the analysis. General geometry is permitted. Detailed user input and output specifications are provided and discussed with example runstreams. To date, LATDYN has been configured for CDC/NOS and DEC VAX/VMS machines. All coding is in ANSII-77 FORTRAN. Detailed instructions regarding interfaces with particular computer operating systems and file structures are provided
Involving users in the evaluation of apps for specific health conditions
With rapid growth of Internet accessibility over recent years, the way in which we engage with healthcare services and make decisions about our own healthcare has changed. One form of engagement with the Internet is through the use of mobile applications (apps) via mobile devices such as smartphones and tablets. As a result of this, many apps have been developed to target people with varying long term conditions. These apps may aim to help educate individuals about their condition or help them to manage it. Assessing the quality of these apps is crucial especially when considering the risks associated with providing misleading information or unsubstantiated claims. This has led to a growing body of research assessing the quality of apps aimed at people living with varying long term conditions. These attempts have not involved service users to address the suitability of apps for their intended target audiences. This paper presents two examples of how service users and associated healthcare professionals can be involved in the suitability assessment of mobile apps for children and young people with Attention Deficit Hyperactivity Disorder and those living with dementia
Diabetes and kidney cancer: A direct or indirect association?
A positive association between diabetes and kidney cancer has been reported in several investigations, but it is unclear whether diabetes or its complications account for this association. Recent advances in estimating direct associations may be useful for elucidating the association between diabetes and kidney cancer. Therefore, we performed a case-control analysis to evaluate whether the direct association between diabetes and kidney cancer is the primary concern in this exposure-outcome relation. Discharge data (with International Classification of Diseases – 9 codes) from 2001 for hospitals throughout Florida were used to construct a case-control population of inpatients aged ≥45 years. Cases (n=1,909) were inpatients with malignant kidney cancer and controls (n=6,451) were inpatients with motor vehicle injuries. Diabetes status was ascertained for cases and controls. Covariates that required adjustment to estimate the total (age, gender, ethnicity, obesity, and smoking) and direct (age, gender, ethnicity, obesity, smoking, hypertension, and kidney disease) associations were identified in a directed acyclic graph. Binary logistic regression was used to estimate the adjusted total and direct odds ratios (ORs) and corresponding 95% confidence intervals (CIs) of kidney cancer for diabetics. The odds of kidney cancer were higher for inpatients with diabetes than inpatients without diabetes when estimating the total association (OR=1.27, 95%CI: 1.10, 1.47) but attenuated when estimating the direct association (OR=1.08, 95%CI: 0.93, 1.25). Our findings provide preliminary insight that the direct association between diabetes and kidney cancer may not be the primary concern in this exposure-outcome relation; indirect pathways (i.e. diabetic complications) may have greater influence on this relation. A similar analysis using longitudinal data with appropriately measured covariates may provide more definitive conclusions and could have implications for kidney cancer prevention among diabetics
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