International Health Research and the Emergence of Global Health in the Late Twentieth Century

An influential policy network emerged from two overlapping developments of the 1970s and 1980s: new research programs focusing on tropical diseases and debates about how to implement the concept of primary health care at the World Health Organization. Participating actors came together in an informal network that, by the late 1980s, expanded advocacy to include the promotion and reorganization of all forms of research that might improve health in the Global South. This goal became associated with a search for new research methods for determining priorities, a quest that reached a peak in the early 1990s when the World Bank entered the picture. The bank brought money, economic analyses, and neoliberal ideology to the research advocacy movement and helped stimulate an upsurge of cost-effective forms of economic thinking in global health (GH) circles. This expanded research network provided some of the conceptual foundations and leadership for several of the most emblematic institutions of the new GH. These included new organizations to bring together and coordinate public and private actors in pursuit of common aims and new forms of economic rationality. The network's advocacy work contributed as well to a massive expansion of GH research at the turn of the century

Motivación emprendedora y teoría de los stakeholders

Este trabajo desarrolla una justificación para la teoría de los stakeholders basada en las motivaciones. La metodología utilizada es diferente y complementaria de la usada en trabajos anteriores, que imponen consideraciones normativas a esta teoría. Enfocado al proceso emprendedor, analiza los mecanismos que explican las acciones y el alineamiento de los distintos participantes. El argumento principal es que cada grupo de interés actúa motivado tanto por el resultado de sus acciones como por el aprendizaje que genera el proceso en sí mismo. A su vez, ese proceso, como motivación central, provee una identidad individual y colectiva y, en su último término, explica el alineamiento de los distintos grupos. Este argumento tiene implicaciones tanto a nivel directivo como normativo

Operator product expansion and the short distance behavior of 3-flavor baryon potentials

The short distance behavior of baryon-baryon potentials defined through Nambu-Bethe-Salpeter wave functions is investigated using the operator product expansion. In a previous analysis of the nucleon-nucleon case, corresponding to the SU(3) channels $27_s$ and $\overline{10}_a$, we argued that the potentials have a repulsive core. A new feature occurs for the case of baryons made up of three flavors: manifestly asymptotically attractive potentials appear in the singlet and octet channels. Attraction in the singlet channel was first indicated by quark model considerations, and recently been found in numerical lattice simulations. The latter have however not yet revealed asymptotic attraction in the octet channels; we give a speculative explanation for this apparent discrepancy.Comment: 11 pages, 2 figure

Lattice Spacing Dependence of the First Order Phase Transition for Dynamical Twisted Mass Fermions

Lattice QCD with Wilson fermions generically shows the phenomenon of a first order phase transition. We study the phase structure of lattice QCD using Wilson twisted mass fermions and the Wilson plaquette gauge action are used in a range of beta values where such a first order phase transition is observed. In particular, we investigate the dependence of the first order phase transition on the value of the lattice spacing. Using only data in one phase and neglecting possible problems arising from the phase transition we are able to perform a first scaling test for physical quantities using this action.Comment: 15 pages, 7 figures, typo corrected, web-list of authors correcte

Scaling, asymptotic scaling and Symanzik improvement. Deconfinement temperature in SU(2) pure gauge theory

We report on a high statistics simulation of SU(2) pure gauge field theory at finite temperature, using Symanzik action. We determine the critical coupling for the deconfinement phase transition on lattices up to 8 x 24, using Finite Size Scaling techniques. We find that the pattern of asymptotic scaling violation is essentially the same as the one observed with conventional, not improved action. On the other hand, the use of effective couplings defined in terms of plaquette expectation values shows a precocious scaling, with respect to an analogous analysis of data obtained by the use of Wilson action, which we interpret as an effect of improvement.Comment: 43 pages ( REVTeX 3.0, self-extracting shell archive, 13 PostScript figs.), report IFUP-TH 21/93 (2 TYPOS IN FORMULAS CORRECTED,1 CITATION UPDATED,CITATIONS IN TEXT ADDED

Infinite Volume and Continuum Limits of the Landau-Gauge Gluon Propagator

We extend a previous improved action study of the Landau gauge gluon propagator, by using a variety of lattices with spacings from $a = 0.17$ to 0.41 fm, to more fully explore finite volume and discretization effects. We also extend a previously used technique for minimizing lattice artifacts, the appropriate choice of momentum variable or ``kinematic correction'', by considering it more generally as a ``tree-level correction''. We demonstrate that by using tree-level correction, determined by the tree-level behavior of the action being considered, it is possible to obtain scaling behavior over a very wide range of momenta and lattice spacings. This makes it possible to explore the infinite volume and continuum limits of the Landau-gauge gluon propagator.Comment: 24 pages RevTex, 18 figures; Responses to referee comments, minor change

Heavy-light mesons with staggered light quarks

We demonstrate the viability of improved staggered light quarks in studies of heavy-light systems. Our method for constructing heavy-light operators exploits the close relation between naive and staggered fermions. The new approach is tested on quenched configurations using several staggered actionsn combined with nonrelativistic heavy quarks. The B_s meson kinetic mass, the hyperfine and 1P-1S splittings in B_s, and the decay constant f_{B_s} are calculated and compared to previous quenched lattice studies. An important technical detail, Bayesian curve-fitting, is discussed at length.Comment: 38 pages, figures included. v2: Entry in Table IX corrected and other minor changes, version appearing in Phys. Rev.

Transient reduction of tinnitus intensity is marked by concomitant reductions of delta band power

<p>Abstract</p> <p>Background</p> <p>Tinnitus is an auditory phantom phenomenon characterized by the sensation of sounds without objectively identifiable sound sources. To date, its causes are not well understood. Previous research found altered patterns of spontaneous brain activity in chronic tinnitus sufferers compared to healthy controls, yet it is unknown whether these abnormal oscillatory patterns are causally related to the tinnitus sensation. Partial support for this notion comes from a neurofeedback approach developed by our group, in which significant reductions in tinnitus loudness could be achieved in patients who successfully normalized their patterns of spontaneous brain activity. The current work attempts to complement these studies by scrutinizing how modulations of tinnitus intensity alter ongoing oscillatory activity.</p> <p>Results</p> <p>In the present study the relation between tinnitus sensation and spontaneous brain activity was investigated using residual inhibition (RI) to reduce tinnitus intensity and source-space projected magnetencephalographic (MEG) data to index brain activity. RI is the sustained reduction (criteria: 50% for at least 30 s) in tinnitus loudness after cessation of a tonal tinnitus masker. A pilot study (n = 38) identified 10 patients who showed RI. A significant reduction of power in the delta (1.3–4.0 Hz) frequency band was observed in temporal regions during RI (p ≤ 0.001).</p> <p>Conclusion</p> <p>The current results suggest that changes of tinnitus intensity induced by RI are mediated by alterations in the pathological patterns of spontaneous brain activity, specifically a reduction of delta activity. Delta activity is a characteristic oscillatory activity generated by deafferented/deprived neuronal networks. This implies that RI effects might reflect the transient reestablishment of balance between excitatory and inhibitory neuronal assemblies, via reafferentation, that have been perturbed (in most tinnitus individuals) by hearing damage. As enhancements have been reported in the delta frequency band for tinnitus at rest, this result conforms to our assumption that a normalization of oscillatory properties of cortical networks is a prerequisite for attenuating the tinnitus sensation. For RI to have therapeutic significance however, this normalization would have to be stabilized.</p

Application of the operator product expansion to the short distance behavior of nuclear potentials

We investigate the short distance behavior of nucleon-nucleon (NN) potentials defined through Bethe-Salpeter wave functions, by perturbatively calculating anomalous dimensions of 6-quark operators in QCD. Thanks to the asymptotic freedom of QCD, 1-loop computations give certain exact results for the potentials in the zero distance limit. In particular the functional form of the S-state central NN potential at short distance $r$ is predicted to be a little weaker than $r^{-2}$. On the other hand, due to the intriguing character of the anomalous dimension spectrum, perturbative considerations alone can not determine whether this potential is repulsive or attractive at short distances. A crude estimation suggests that the force at short distance is repulsive, as found numerically in lattice QCD. A similar behavior is found for the tensor potential.Comment: 40 pages, no figure