Cardiovascular responses of conscious rats to carotid body chemoreceptor stimulation by intravenous KCN

This multicentre, double-blind, randomised, crossover study compared the efficacy, safety and tolerability of subcutaneous sumatriptan (6 mg and 12 mg) with placebo in 134 in-patients with cluster headache. Headache improvement to mild or no pain at 5, 10 and 15 min after treatment was recorded. At 10 min, headache relief was reported by 25% (placebo), 49% (6 mg) and 63% (12 mg) of patients and at 15 min the results were 35% (placebo), 75% (6 mg) and 80% (12 mg) (p < 0.001 for all comparisons with placebo). The 12 mg dose was not significantly better than the 6 mg dose and was associated with more adverse events. The 6 mg dose is therefore recommended for the acute treatment of cluster headache.     

Inelastic hot-electron Bloch scattering from quantum-confined systems

The phenomena of electric field-assisted inelastic Bloch-electron scattering from an atomically confined bound-state electron is reported. A novel formalism for treating Bloch electron dynamics and quantum transport in electric fields of arbitrary strength and time dependence is utilized. The two-electron inelastic scattering rate obtained herein shows an electric field-dependent broadening; as a novel addition, the calculated scattering rate includes an explicit dependence on band structure, predicting a strong influence from band non-parabolicity and anisotropy.     

Clustering multidimensional sequences in spatial and temporal databases

Many environmental, scientific, technical or medical database applications require effective and efficient mining of time series, sequences or trajectories of measurements taken at different time points and positions forming large temporal or spatial databases. Particularly the analysis of concurrent and multidimensional sequences poses new challenges in finding clusters of arbitrary length and varying number of attributes. We present a novel algorithm capable of finding parallel clusters in different subspaces and demonstrate our results for temporal and spatial applications. Our analysis of structural quality parameters in rivers is successfully used by hydrologists to develop measures for river quality improvements.

Fast empirical pKa prediction by Ewald summation

pK(a) calculations for macromolecules are normally performed by solving the Poisson-Boltzmann equation, accounting for the different dielectric constants of solvent and solute, as well as the ionic strength. Despite the large number of successful applications, there are some situations where the current algorithms are not suitable: (1) large scale, high-throughput analysis which requires calculations to be completed within a fraction of a second, e.g. when permanently monitoring pK(a) shifts during a molecular dynamics simulation; (2) prediction of pK(a)s in periodic boundaries, e.g. when reconstructing entire protein crystal unit cells from PDB files, including the correct protonation patterns at experimental pH. Such in silico crystals are needed by 'self-parameterizing' molecular dynamics force fields like YASARA YAMBER, that optimize their parameters while energy-minimizing high-resolution protein crystals. To address both problems, we define an empirical equation that expresses the pK(a) as a function of electrostatic potential, hydrogen bonds and accessible surface area. The electrostatic potential is evaluated by Ewald summation, which captures periodic crystal environments and the uncertainty in atom positions using Gaussian charge densities. The empirical proportionality constants are derived from 217 experimentally determined pK(a)s, and despite its simplicity, this pK(a) calculation method reaches a high overall jack-knifed accuracy, and is fast enough to be used during a molecular dynamics simulation. A reliable null-model to judge pK(a) prediction accuracies is also presented.     

Dielectric loss microwave degradation of polymers: Cellulose

The pyrolysis of organic waste polymers to produce fuels and chemicals is of interest to augment petroleum-based processes. The wide variety of pyrolysis products of low yield and the uncertain role that heat transfer rate plays in determining these have been deterrents to utilization in the past. A possible approach to increased selectivity for products is to heat them rapidly and homogeneously with the aim of narrowing the product distribution. A very rapid means of homogeneous heat transfer throughout the substrate is microwave heating. A laboratory study has been done to determine what effect high-intensity microwave energy has on the thermal degradative pathways of cellulose. The product distribution found when cellulose is pyrolyzed in the absence of a microwave discharge is similar to that found in conventional furnace pyrolysis. The major products are levoglucosan (27%), carbon dioxide (2–5%), water, and charred residue. However, the total heat-up and reaction times for even large pellets are reduced to less than 2–3 min when high-intensity microwave irradiation is employed. Effects of pressure and microwave power are reported. Low external gas temperature also prevents secondary reactions.     

Sleep-related respiratory disorders

Sleep-related respiratory disorders are mainly represented by the consequences of partial or total upper airway obstruction during sleep, which lead to clinical pictures ranging from "pure" snoring to full-blown obstructive sleep apnea syndrome, including obstructive sleep hypopnea syndrome and upper airway resistance syndrome. These pictures share symptoms like snoring and excessive daytime sleepiness. Beyond the social and professional impairment and the increased risk of traffic and work accidents, these patients are exposed to the complications of systemic hypertension, which is often associated, and of less frequent cardiorespiratory failure. The diagnosis is based upon polysomnography which demonstrates the ventilation abnormalities. Since stable weight loss is most often impossible to obtain, the treatment of choice is based on nasal continuous positive airway pressure during sleep. In some selected cases, facial bone surgery may be helpful.     

Instantaneous characterization of time varying nonlinear systems[neurophysiological responses]

A nonlinear system may be characterized by an orthogonal functional power series (FPS) computed from cross correlations between input and output variables. "Is the response changing over the course of the experiment?" is a fundamental question encountered in the analysis of both FPS and evoked potentials (EP's). Regression on closed-form functions of time produces a time-varying FPS or EP. Evaluation of these functions at a specified time point produces a system characterization for that instant.     

New contributions to clinical hypertension from molecular biology

The authors constructed a new dynamic guiding splint assisting the active mobilisation after flexor tendon repair distal to the wrist. In these cases, the "inverse" wrist position seems to be the best position for mobilisation. This means that finger flexion should be carried out during wrist extension, and finger extension during wrist flexion. The splint guides and co-ordinates the movements of the wrist and the fingers, and it limits the free usage of the hand.