Finite-Time Singularity Signature of Hyperinflation

We present a novel analysis extending the recent work of Mizuno et al. [2002] on the hyperinflations of Germany (1920/1/1-1923/11/1), Hungary (1945/4/30-1946/7/15), Brazil (1969-1994), Israel (1969-1985), Nicaragua (1969-1991), Peru (1969-1990) and Bolivia (1969-1985). On the basis of a generalization of Cagan's model of inflation based on the mechanism of ``inflationary expectation'' or positive feedbacks between realized growth rate and people's expected growth rate, we find that hyperinflations can be characterized by a power law singularity culminating at a critical time $t_c$. Mizuno et al.'s double-exponential function can be seen as a discrete time-step approximation of our more general nonlinear ODE formulation of the price dynamics which exhibits a finite-time singular behavior. This extension of Cagan's model, which makes natural the appearance of a critical time $t_c$, has the advantage of providing a well-defined end of the clearly unsustainable hyperinflation regime. We find an excellent and reliable agreement between theory and data for Germany, Hungary, Peru and Bolivia. For Brazil, Israel and Nicaragua, the super-exponential growth seems to be already contaminated significantly by the existence of a cross-over to a stationary regime.Comment: Latex 21 pages including 2 tables and 7 eps figure

Ground State Energy of the Low Density Bose Gas

Now that the properties of low temperature Bose gases at low density, $\rho$, can be examined experimentally it is appropriate to revisit some of the formulas deduced by many authors 4-5 decades ago. One of these is that the leading term in the energy/particle is $2\pi \hbar^2 \rho a/m$, where $a$ is the scattering length. Owing to the delicate and peculiar nature of bosonic correlations, four decades of research have failed to establish this plausible formula rigorously. The only known lower bound for the energy was found by Dyson in 1957, but it was 14 times too small. The correct bound is proved here.Comment: 4 pages, Revtex, reference 12 change

Siren songs or path to salvation? Interpreting the visions of web technology at a UK regional newspaper in crisis, 2006-11

A 5-year case study of an established regional newspaper in Britain investigates journalists about their perceptions of convergence in digital technologies. This research is the first ethnographic longitudinal case study of a UK regional newspaper. Although conforming to some trends observed in the wider field of scholarship, the analysis adds to skepticism about any linear or directional views of innovation and adoption: the Northern Echo newspaper journalists were observed to have revised their opinions of optimum Web practices, and sometimes radically reversed policies. Technology is seen in the period as a fluid, amorphous entity. Central corporate authority appeared to diminish in the period as part of a wider reduction in formalism. Questioning functionalist notions of the market, the study suggests cause and effect models of change are often subverted by contradictory perceptions of particular actions. Meanwhile, during technological evolution, the ‘professional imagination’ can be understood as strongly reflecting the parent print culture and its routines, despite pioneering a new convergence partnership with an independent television company

The processing of number scales beyond whole numbers in development: Dissociations in arithmetic in Turner’s syndrome

The arithmetical skills in two children with Turner’s syndrome (TS), each the focus of a case study, were analysed in whole numbers and other number scales that have not been systematically explored previously, fractions, decimals, percentages, and negative numbers. The intention was to identify the fractionation of arithmetical skills. The two girls with TS showed dissociations of arithmetical skill in the calculation system of whole numbers that support its modular organization. Fractionation of skills was observed in some components of the other number scales, suggesting an analogous organization within these scales. The operational specificity of impairment within number scales but not others argued against a unitary arithmetical system but rather for autonomous operational scales within distinct number scales. A general model of arithmetic is proposed

Cells Isolated from Cadaveric Bone Marrow are Safe for Use in Bone Healing and Effective at Promoting Osteogenic Re-construction

The efficacy and immune-modulation of mesenchymal stem cells is well documented. The issue of obtaining mesenchymal stem cells without patient risk, extensive intra-operative procedure, cell manipulation or exposure of cells to harmful reagents remains an issue. This study was designed to test the viability, composition and osteogenic potential of cells derived from cadaveric bone marrow by a new process. Vertebral bone from cadavers was collected within 24 hours of death, processed by a new procedure of tumbling and collection, and evaluated for viability, marker expression, cell composition, and inflammatory properties at various stages of the isolation process and following cryopreservation. Viability was excellent in all fractions and at all stages of the study. Cell staining and microscopic observation showed increased erythrocyte content in the first tumble of bone for marrow extraction, as well as gross observation of debris. Cryopreservation favored the preservation of CD45-/CD105+ and GlycoA-/STRO-1+ mesenchymal stem cells at the expense of platelets, red blood cells, white blood cells and neutrophils. The resulting cell solution contains a percentage of mesenchymal stem cells far above that required for immune modulation. A mixed lymphocyte reaction assay showed no inflammatory response to this cell composition. The cells produced and preserved in this manner are viable, should elicit no immune response, suppress recipient immune responses and osteogenically differentiate