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The European Commission's Proposal for a Financial Transactions Tax: A Critical Assessment
A financial activities tax (FAT) and a financial transactions tax (FTT) are the main alternative ways of recouping some of the public money used to bail out the financial sector after the great crisis of 2007–08. In preparing a common proposal for the European Union, the European Commission initially appeared to favour the FAT, but then swung its weight behind the FTT in late 2011. Its rationale was that in addition to generating revenue, this tax could also help to stabilize the financial markets by curbing excessive speculative trading. This article takes a different position. Its central argument is that the FTT would amplify rather than dampen market instability by interfering with the functions of important financial institutions. Its chief conclusion is that the FAT is superior to the FTT
Combustion in thermonuclear supernova explosions
Type Ia supernovae are associated with thermonuclear explosions of white
dwarf stars. Combustion processes convert material in nuclear reactions and
release the energy required to explode the stars. At the same time, they
produce the radioactive species that power radiation and give rise to the
formation of the observables. Therefore, the physical mechanism of the
combustion processes, as reviewed here, is the key to understand these
astrophysical events. Theory establishes two distinct modes of propagation for
combustion fronts: subsonic deflagrations and supersonic detonations. Both are
assumed to play an important role in thermonuclear supernovae. The physical
nature and theoretical models of deflagrations and detonations are discussed
together with numerical implementations. A particular challenge arises due to
the wide range of spatial scales involved in these phenomena. Neither the
combustion waves nor their interaction with fluid flow and instabilities can be
directly resolved in simulations. Substantial modeling effort is required to
consistently capture such effects and the corresponding techniques are
discussed in detail. They form the basis of modern multidimensional
hydrodynamical simulations of thermonuclear supernova explosions. The problem
of deflagration-to-detonation transitions in thermonuclear supernova explosions
is briefly mentioned.Comment: Author version of chapter for 'Handbook of Supernovae,' edited by A.
Alsabti and P. Murdin, Springer. 24 pages, 4 figure
The future of hyperdiverse tropical ecosystems
The tropics contain the overwhelming majority of Earth’s biodiversity: their terrestrial, freshwater and marine ecosystems hold more than three-quarters of all species, including almost all shallow-water corals and over 90% of terrestrial birds. However, tropical ecosystems are also subject to pervasive and interacting stressors, such as deforestation, overfishing and climate change, and they are set within a socio-economic context that includes growing pressure from an increasingly globalized world, larger and more affluent tropical populations, and weak governance and response capacities. Concerted local, national and international actions are urgently required to prevent a collapse of tropical biodiversity
Effective Rheology of Bubbles Moving in a Capillary Tube
We calculate the average volumetric flux versus pressure drop of bubbles
moving in a single capillary tube with varying diameter, finding a square-root
relation from mapping the flow equations onto that of a driven overdamped
pendulum. The calculation is based on a derivation of the equation of motion of
a bubble train from considering the capillary forces and the entropy production
associated with the viscous flow. We also calculate the configurational
probability of the positions of the bubbles.Comment: 4 pages, 1 figur
Do ethnobotanical and laboratory data predict clinical safety and efficacy of anti-malarial plants?
<p>Abstract</p> <p>Background</p> <p>Over 1200 plant species are reported in ethnobotanical studies for the treatment of malaria and fevers, so it is important to prioritize plants for further development of anti-malarials.</p> <p>Methods</p> <p>The “RITAM score” was designed to combine information from systematic literature searches of published ethnobotanical studies and laboratory pharmacological studies of efficacy and safety, in order to prioritize plants for further research. It was evaluated by correlating it with the results of clinical trials.</p> <p>Results and discussion</p> <p>The laboratory efficacy score correlated with clinical parasite clearance (r<sub>s</sub>=0.7). The ethnobotanical component correlated weakly with clinical symptom clearance but not with parasite clearance. The safety component was difficult to validate as all plants entering clinical trials were generally considered safe, so there was no clinical data on toxic plants.</p> <p>Conclusion</p> <p>The RITAM score (especially the efficacy and safety components) can be used as part of the selection process for prioritising plants for further research as anti-malarial drug candidates. The validation in this study was limited by the very small number of available clinical studies, and the heterogeneity of patients included.</p
Hypertension and type 2 diabetes: What family physicians can do to improve control of blood pressure - an observational study
Background: The prevalence of type 2 diabetes is rising, and most of these patients also have hypertension,
substantially increasing the risk of cardiovascular morbidity and mortality. The majority of these patients do not
reach target blood pressure levels for a wide variety of reasons. When a literature review provided no clear focus
for action when patients are not at target, we initiated a study to identify characteristics of patients and providers
associated with achieving target BP levels in community-based practice.
Methods: We conducted a practice- based, cross-sectional observational and mailed survey study. The setting was
the practices of 27 family physicians and nurse practitioners in 3 eastern provinces in Canada. The participants
were all patients with type 2 diabetes who could understand English, were able to give consent, and would be
available for follow-up for more than one year. Data were collected from each patient’s medical record and from
each patient and physician/nurse practitioner by mailed survey. Our main outcome measures were overall blood
pressure at target (< 130/80), systolic blood pressure at target, and diastolic blood pressure at target. Analysis
included initial descriptive statistics, logistic regression models, and multivariate regression using hierarchical
nonlinear modeling (HNLM).
Results: Fifty-four percent were at target for both systolic and diastolic pressures. Sixty-two percent were at systolic
target, and 79% were at diastolic target. Patients who reported eating food low in salt had higher odds of
reaching target blood pressure. Similarly, patients reporting low adherence to their medication regimen had lower
odds of reaching target blood pressure.
Conclusions: When primary care health professionals are dealing with blood pressures above target in a patient
with type 2 diabetes, they should pay particular attention to two factors. They should inquire about dietary salt
intake, strongly emphasize the importance of reduction, and refer for detailed counseling if necessary. Similarly,
they should inquire about adherence to the medication regimen, and employ a variety of patient-oriented
strategies to improve adherence
Human Umbilical Cord Blood Cells Restore Brain Damage Induced Changes in Rat Somatosensory Cortex
Intraperitoneal transplantation of human umbilical cord blood (hUCB) cells has been shown to reduce sensorimotor deficits after hypoxic ischemic brain injury in neonatal rats. However, the neuronal correlate of the functional recovery and how such a treatment enforces plastic remodelling at the level of neural processing remains elusive. Here we show by in-vivo recordings that hUCB cells have the capability of ameliorating the injury-related impairment of neural processing in primary somatosensory cortex. Intact cortical processing depends on a delicate balance of inhibitory and excitatory transmission, which is disturbed after injury. We found that the dimensions of cortical maps and receptive fields, which are significantly altered after injury, were largely restored. Additionally, the lesion induced hyperexcitability was no longer observed in hUCB treated animals as indicated by a paired-pulse behaviour resembling that observed in control animals. The beneficial effects on cortical processing were reflected in an almost complete recovery of sensorimotor behaviour. Our results demonstrate that hUCB cells reinstall the way central neurons process information by normalizing inhibitory and excitatory processes. We propose that the intermediate level of cortical processing will become relevant as a new stage to investigate efficacy and mechanisms of cell therapy in the treatment of brain injury
Transmembrane protein PERP is a component of tessellate junctions and of other junctional and non-junctional plasma membrane regions in diverse epithelial and epithelium-derived cells
Protein PERP (p53 apoptosis effector related to PMP-22) is a small (21.4 kDa) transmembrane polypeptide with an amino acid sequence indicative of a tetraspanin character. It is enriched in the plasma membrane and apparently contributes to cell-cell contacts. Hitherto, it has been reported to be exclusively a component of desmosomes of some stratified epithelia. However, by using a series of newly generated mono- and polyclonal antibodies, we show that protein PERP is not only present in all kinds of stratified epithelia but also occurs in simple, columnar, complex and transitional epithelia, in various types of squamous metaplasia and epithelium-derived tumors, in diverse epithelium-derived cell cultures and in myocardial tissue. Immunofluorescence and immunoelectron microscopy allow us to localize PERP predominantly in small intradesmosomal locations and in variously sized, junction-like peri- and interdesmosomal regions (“tessellate junctions”), mostly in mosaic or amalgamated combinations with other molecules believed, to date, to be exclusive components of tight and adherens junctions. In the heart, PERP is a major component of the composite junctions of the intercalated disks connecting cardiomyocytes. Finally, protein PERP is a cobblestone-like general component of special plasma membrane regions such as the bile canaliculi of liver and subapical-to-lateral zones of diverse columnar epithelia and upper urothelial cell layers. We discuss possible organizational and architectonic functions of protein PERP and its potential value as an immunohistochemical diagnostic marker
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