Real Exchange Rates Over the Past Two Centuries : How Important is the Harrod-Balassa-Samuelson Effect?

Using data since 1820 for the US, the UK and France, we test for the presence of real effects on the equilibrium real exchange rate (the Harrod-Balassa-Samuelson, HBS effect) in an explicitly nonlinear framework and allowing for shifts in real exchange rate volatility across nominal regimes. A statistically signifcant HBS effect for sterling-dollar captures its longrun trend and explains a proportion of variation in changes in the real rate that is proportional to the time horizon of the change. There is signifcant evidence of nonlinear reversion towards long-run equilibrium and downwards shifts in volatility during &xed nominal exchange rate regimes.purchasing power parity ; real exchange rate ; nonlinear dynamics ; Harrod-Balassa-Samuelson effect ; productivity differentials

Growth and development of the human intervertebral disc

The object of this study is to compare the growth and development of a lumbar intervertebral disc with those in the thoracic and cervical regions from embryonic life to childhood. Particular attention is paid to changes during and following the establishment of the secondary curvatures of the vertebral column. Current knowledge of development of the intervertebral disc is reviewed.Postmortem material from 67 cases and a large series of radiographs are used in histological and mensural studies. The vertical dimensions of the 'total disc' (which includes the cartilage plates), its parts, and the vertebral body above the disc are measured in each region at every age. Notochordal remnants in vertebrae and discs are used as 'natural markers' from which horizontal dimensions are measured in the median plane to give an indication of growth anteriorly and posteriorly from the position of the notochord.Notochordal cells appear to multiply during foetal life and infancy, playing an important role in growth and extension of the notochordal nucleus pulposus up to about three years, but they degenerate and disappear from about three to seven years.As the notochordal nucleus pulposus grows rapidly in V volume, principally by increase in its macoid matrix (notably in lumbar discs), the anulus fibrosus and cartilage plates bounding it become thinner. Associated with thinning of the cartilage plates, vertical growth of the central part of the 'total disc' slows down during the first two postnatal years.As secondary cervical and lumbar curvatures are established, the cervical and lumbar notochordal nuclei pulposi respectively move to more anterior and central positions, but the thoracic notochordal nucleus pulposus remains posteriorly situated. From two years onwards, the central parts of lumbar discs grow rapidly in height though the heights of the central parts of thoracic discs remain almost unchanged. The central situation of the lumbar nucleus pulposus in childhood, and the rapid increase in height of the central part of the lumbar 'total disc' from two to seven years are associated with corresponding changes in the shape of the cephalic and caudal end surfaces of lumbar vertebral bodies from convexity to concavity.During the same period (about two to seven years) there is an increase in the rate of antero- posterior growth of the lumbar vertebral column without any increase in its lateral growth rate.The present investigation throws further light on the work of Houston and Zaleski (1967) who demonstrate a relationship between 'activity' and vertebral body shape, and suggests that the rate of anteroposterior growth of the lumbar vertebral column, the vi the rate of vertical growth of lumbar vertebrae and 'total discs', and their changes in shape during childhood, all depend to some extent on the assumption of the normal erect posture

Technical guide on documentation requirements for open market contract acquisitions of information resources

A guide is presented to assist requestors in formulating and submitting the required Complete Package for Information Resources (IR) acquisitions. Advance discussions with cognizant procurement personnel are strongly recommended for complex IR requirements or for those requestors new to the acquisition process. Open Market means the requirement either is not available on GSA Schedule Contract or exceeds the $300,000 threshold and/or the quantity Maximum Order Limitation of the GSA Schedule Contract. Only open market contract acquisitions (i.e., in excess of the$25,000 small purchase threshold), are addressed

Bromocriptine: Its place in type 2 diabetes Tx

For obese patients with type 2 diabetes (T2D) who do not tolerate other diabetes medications or for patients who need only a minimal reduction in glycosylated hemoglobin (A1c) to reach goal, bromocriptine may be a therapeutic agent to consider

Evaluating the Applicability of the Fokker-Planck Equation in Polymer Translocation: A Brownian Dynamics Study

Brownian dynamics (BD) simulations are used to study the translocation dynamics of a coarse-grained polymer through a cylindrical nanopore. We consider the case of short polymers, with a polymer length, N, in the range N=21-61. The rate of translocation is controlled by a tunable friction coefficient, gamma_{0p}, for monomers inside the nanopore. In the case of unforced translocation, the mean translocation time scales with polymer length N as ~ (N-N_p)^alpha, where N_p is the average number of monomers in the nanopore. The exponent approaches the value alpha=2 when the pore friction is sufficiently high, in accord with the prediction for the case of the quasi-static regime where pore friction dominates. In the case of forced translocation, the polymer chain is stretched and compressed on the cis and trans sides, respectively, for low gamma_{0p}. However, the chain approaches conformational quasi-equilibrium for sufficiently large gamma_{0p}. In this limit the observed scaling of with driving force and chain length supports the FP prediction that is proportional to N/f_d for sufficiently strong driving force. Monte Carlo simulations are used to calculate translocation free energy functions for the system. The free energies are used with the Fokker-Planck equation to calculate translocation time distributions. At sufficiently high gamma_{0p}, the predicted distributions are in excellent agreement with those calculated from the BD simulations. Thus, the FP equation provides a valid description of translocation dynamics for sufficiently high pore friction for the range of polymer lengths considered here. Increasing N will require a corresponding increase in pore friction to maintain the validity of the FP approach. Outside the regime of low N and high pore friction, the polymer is out of equilibrium, and the FP approach is not valid.Comment: 13 pages, 11 figure