We consider gamma-ray burst outflows with a substantial neutron component that are either dominated by thermal energy (fireballs) or by magnetic energy. In the latter case, we focus on the recently ...introduced “AC” model which relies on magnetic reconnection to accelerate the flow and power the prompt emission. For both the fireball and the AC model, we investigate the dynamical importance of neutrons on the outflow. We study particle creation in inelastic neutron-proton collisions and find that in both models the resulting neutrino emission is too weak to be detectable. The inelastic collisions also produce γ-rays, which create pairs in interactions with soft photons carried with the flow. In magnetically driven outflows, the energy of these pairs is radiated away as synchrotron emission. The bulk of the emission takes place at a few hundred keV, which makes it difficult to disentangle this signal from the prompt emission. In fireballs, however, pair cascading leads to the emission of γ-rays with observer energy in the range of 2–20 GeV and a fluence well above the GLAST threshold. Therefore this emission can be a useful diagnostic of the nature of the outflow.
Background
To improve the quality of exercise-based cardiac rehabilitation (CR) in patients with coronary heart disease (CHD) the CR guideline from the Dutch Royal Society for Physiotherapists (KNGF) ...has been updated. This guideline can be considered an addition to the 2011 Dutch Multidisciplinary CR guideline, as it includes several novel topics.
Methods
A systematic literature search was performed to formulate conclusions on the efficacy of exercise-based interventions during all CR phases in patients with CHD. Evidence was graded (1–4) according the Dutch evidence-based guideline development (EBRO) criteria. In case of insufficient scientific evidence, recommendations were based on expert opinion. This guideline comprised a structured approach including assessment, treatment and evaluation.
Results
Recommendations for exercise-based CR were formulated covering the following topics: preoperative physiotherapy, mobilisation during the clinical phase, aerobic exercise, strength training, and relaxation therapy during the outpatient rehabilitation phase, and adoption and monitoring of a physically active lifestyle after outpatient rehabilitation.
Conclusions
There is strong evidence for the effectiveness of exercise-based CR during all phases of CR. The implementation of this guideline in clinical practice needs further evaluation as well as the maintenance of an active lifestyle after supervised rehabilitation.
The appearance of a reaction profile or potential energy surface (PES) associated with the reaction path (defined as the path of steepest descent from the saddle point) depends on the choice of ...reaction coordinate onto which the intrinsic reaction coordinate is projected. This provides one with the freedom, but also the problem, of choosing the optimal perspective (i.e., the optimal reaction coordinate) for revealing what is essential for understanding the reaction. Here, we address this issue by analyzing a number of different reaction coordinates for the same set of model reactions, namely, prototypical oxidative addition reactions of C−X bonds to palladium. We show how different choices affect the appearance of the PES, and we discuss which qualities make a particular reaction coordinate most suitable for comparing and analyzing the reactions. Furthermore, we show how the transition vector (i.e., the normal mode associated with a negative force constant that leads from the saddle point to the steepest descent paths) can serve as a useful and computationally much more efficient approximation (designated TV-IRC) for full IRC computations, in the decisive region around the transition state.
Rationale
To improve the quality of exercise-based cardiac rehabilitation (CR) in patients with chronic heart failure (CHF) a practice guideline from the Dutch Royal Society for Physiotherapy (KNGF) ...has been developed.
Guideline development
A systematic literature search was performed to formulate conclusions on the efficacy of exercise-based intervention during all CR phases in patients with CHF. Evidence was graded (1–4) according the Dutch evidence-based guideline development criteria.
Clinical and research recommendations
Recommendations for exercise-based CR were formulated covering the following topics: mobilisation and treatment of pulmonary symptoms (if necessary) during the clinical phase, aerobic exercise, strength training (inspiratory muscle training and peripheral muscle training) and relaxation therapy during the outpatient CR phase, and adoption and monitoring training after outpatient CR.
Applicability and implementation issues
This guideline provides the physiotherapist with an evidence-based instrument to assist in clinical decision-making regarding patients with CHF. The implementation of the guideline in clinical practice needs further evaluation.
Conclusion
This guideline outlines best practice standards for physiotherapists concerning exercise-based CR in CHF patients. Research is needed on strategies to improve monitoring and follow-up of the maintenance of a physical active lifestyle after supervised CR.
We investigate the fate of very compact, sudden energy depositions that may lie at the origin of gamma-ray bursts (GRBs). Following on from the work of Cavallo & Rees, we take account of the much ...higher energies now believed to be involved. The main effect of this is that thermal neutrinos are present and energetically important. We show that these may provide sufficient cooling to tap most of the explosion energy. However, at the extreme energies usually invoked for GRBs, the neutrino opacity suffices to prevent dramatic losses, provided that the heating process is sufficiently fast. In a generic case, a few tens of per cent of the initial fireball energy will escape as an isotropic millisecond burst of thermal neutrinos with a temperature of about 60 MeV, which is detectable for nearby GRBs and hypernovae. For parameters we find most likely for GRB fireballs, the dominant processes are purely leptonic and thus the baryon loading of the fireball does not affect our conclusions.
Objectives. We sought to study the effects of catecholamines on myocardial oxygen consumption (V̇o2), regional blood flows and total body V̇o2in lambs with circulatory congestion.
Background. ...Catecholamines are often used to support cardiovascular function in children with circulatory congestion because they increase contractility as well as heart rate. However, these changes increase myocardial oxygen demand and thus can lead to a mismatch between myocardial oxygen supply and demand. Catecholamines can also change regional blood flows and V̇o2unfavorably.
Methods. We infused isoproterenol (0.1 μg/kg body weight per min) and dopamine (10 μg/kg per min) and measured myocardial and total body V̇o2and regional blood flows in chronically instrumented 7-week old lambs with and without a left to right shunt.
Results. Isoproterenol increased myocardial V̇o2, parallel to the increase in heart rate. However, myocardial blood flow and, consequently, oxygen supply also increased. This increase outweighed the increase in myocardial V̇o2, so that myocardial oxygen extraction decreased. Isoproterenol did not change blood flow distribution. Isoproterenol increased total body V̇o2; however, systemic oxygen supply increased even more, so that oxygen extraction decreased and mixed venous oxygen saturation increased. In contrast, dopamine had no or little effect on myocardial V̇o2or blood flow distribution.
Conclusions. We conclude that the catecholamines isoproterenol and dopamine do not lead to a mismatch between myocardial oxygen supply and demand, nor do they change blood flow distribution unfavorably in 7-week old lambs with a left to right shunt. We demonstrated that isoproterenol is superior to dopamine, because it shifts the balance between oxygen supply and consumption toward supply so that systemic oxygen extraction reserve increases.
A 63-year-old man with symptoms of depression and sexual disinhibition was admitted to a psychiatric clinic for the elderly. Because the man’s symptoms rapidly became more severe he was referred to ...the emergency room. There, his illness was diagnosed as paraneoplastic limbic encephalitis with positive anti-Hu antibodies; this is a paraneoplastic neurological syndrome presenting with short-term memory loss, epileptic seizures and psychiatric symptoms. For the prognosis of the illness it is essential that the syndrome is diagnosed as early as possible. Since patients sometimes present with mainly psychiatric symptoms it is important that psychiatrists are fully informed about the symptoms and are able to make an accurate diagnosis.
The purpose of The Telescope Array experiment is to identify origin of the ultra high energy cosmic rays. The Telescope Array is a hybrid detector consists of a surface detector array and air ...fluorescence detectors. This hybrid detector is observing extensive air showers to measure the energy spectrum, anisotropy and composition of Ultra High Energy Cosmic Rays. The detector construction has been completed in March 2008, and the hybrid observation with the full configuration has been running since that time. In this talk, the status of observation and our prospects are described.
Myocardial oxygen demand may be increased in chronically hypoxemic lambs because of their increased heart rate. Therefore, we determined whether left ventricular (LV) oxygen supply, oxygen uptake and ...oxygen demand were proportionally increased in 6-wk-old lambs, after 4 wk of hypoxemia (n = 15), as compared with control lambs (n = 14). In addition, we determined whether LV glucose, pyruvate, lactate, FFA and ketoacids uptake were altered in hypoxemic lambs, because of alterations in arterial glucose, pyruvate and lactate concentrations, that may occur in hypoxemia. Hypoxemia was induced by the combination of an atrial septal defect and pulmonary stenosis. Arterial oxygen saturation was decreased in hypoxemic lambs (67 +/- 8 versus 91 +/- 3%, p < 0.001), Hb concentration was increased, so that arterial oxygen concentration was similar in both groups of lambs. Myocardial mass (61 +/- 13 versus 44 +/- 9 g, p < 0.001) and total myocardial blood flow (117 +/- 36 versus 62 +/- 27 mL.min-1, p < 0.001) were increased, mainly due to right ventricular hypertrophy. LV oxygen demand, estimated by the rate pressure product (2072 +/- 465 versus 1467 +/- 358 kPa.beat.min-1, p < 0.001), and oxygen uptake (723 +/- 223 versus 556 +/- 184 mumol.min-1 x 100 g-1, p < 0.05) were proportionally increased in hypoxemic lambs. LV oxygen supply increased linearly with oxygen uptake (r = 0.96) in all lambs, by adjustments in LV blood flow, which was increased in hypoxemic lambs (168 +/- 41 versus 134 +/- 45 mL.min-1 x 100g-1, p < 0.05).
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