A Kohlrausch Type Equation Based on a Simplified Cooperative Model

The differential equation is analysed, with n denoting the relaxing quantity, n = dn/dt(tis time), and a, band sconstants. Equations of this type have previously been shown to describe a large variety of relaxational patterns. Especially interesting is the close relationship with Bose–Einstein (B–E) like distributions and the underlying induction mechanisms. Here, the focus is on the special case of a= 0 which yields a generalised stretched exponential and, for certain variable ranges, the Kohlrausch (KWW) function in its usual form. The relaxation time is shown to depend strongly on the parameters entering the underlying differential equation. Conditions for constant are given.     

Simple and powerful visual stimulus generator

We describe a cheap, simple, portable and efficient approach to visual stimulation for neurophysiology which does not need any special hardware equipment. The method based on an animation technique uses the FLI autodesk animator format. This form of the animation is replayed by a special program ('player') providing synchronisation pulses toward recording system via parallel port. The 'player is running on an IBM compatible personal computer under MS-DOS operation system and stimulus is displayed on a VGA computer monitor. Various stimuli created with this technique for visual evoked potentials (VEPs) are presented.     

Persistent hyperinsulinemic hypoglycemia in the newborn and infants

Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus.     

Zur Bleichung pflanzlicher Öle II: Kinetik des Bleichprozesses

Bleaching of Vegetable Oils II.: Kinetics of the Bleaching Process The study deals with the kinetics of bleaching. The test-system used rapeseed oil with a low content of erucic acid and added bleaching earth Tonsil Optimum FF. By means of the results obtained an empiric equation was then developed describing the process taking part under the conditions studied.     

Necrotizing colitis after total hysterectomy

After an uneventful hysterectomy for fibroids carried out in a woman of 48 years of age peritonitis developed on the 5th post-operative day. It was due to necrosing sigmoiditis which occurred in spite of normal bowel action having been resumed on the 3rd post-operative day. This is a rare but usually very severe post-operative complication. Immediate operation saved the patient but she had to have two further operative procedures.     

The determination of corrosion rates by electrochemical d.c. and a.c. methods — II. Systems with discontinuous steady state polarization behavior

Corrosion systems exhibiting discontinuous anodic polarization curves have been investigated by steady state polarization, linear sweep polarization, large and small signal pulse polarization, a.c. impedance measurements and solution analysis. It is shown that the true corrosion current density can only be determined if the non-linearity of the system is avoided. This is not possible from analysis of a.c. impedance results without model assumptions.     

Foreperiod and simple reaction time.

Reviews studies of simple visual and auditory reaction processes published since W. H. Teicher (1954), with emphasis on the preparatory phase of these processes, particularly the foreperiod (FP). The 1st section consists of the analysis of actual FP variables; duration, regularity, range, distribution, and preceding FPs. The 2nd section deals with factors affecting the relation between FP and reaction time (RT): (a) the modality, intensity, probability, and duration of the warning signal and reaction stimulus (RS) and (b) the speed–accuracy trade-off. It is suggested that the S's expectancy (momentary probability of the immediate delivery of the RS) is the most important determinant of the preparation to respond to the RS at any moment during a trial and, hence, of RT. Many factors exert their influence on preparation through their effect on expectancy. Other factors have a direct influence on preparation: short-term exhaustion and fatigue, immediate arousal evoked by intense auditory stimuli, the S's stimulus criterion, the speed–accuracy trade-off, and fluctuation in motor preparedness owing to inaccuracies in the control of motor preparation. (4? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Registration and real-time visualization of transcranial magnetic stimulation with 3-D MR images

This paper describes a method for registering and visualizing in real-time the results of transcranial magnetic stimulations (TMS) in physical space on the corresponding anatomical locations in MR images of the brain. The method proceeds in three main steps. First, the patient scalp is digitized in physical space with a magnetic-field digitizer, following a specific digitization pattern. Second, a registration process minimizes the mean square distance between those points and a segmented scalp surface extracted from the magnetic resonance image. Following this registration, the physician can follow the change in coil position in real-time through the visualization interface and adjust the coil position to the desired anatomical location. Third, amplitude of motor evoked potentials can be projected onto the segmented brain in order to create functional brain maps. The registration has subpixel accuracy in a study with simulated data, while we obtain a point to surface root-mean-square error of 1.17+/-0.38 mm in a 24 subject study.     

Impact of infrastructure and local environment on road unsafety. Logistic modeling with spatial autocorrelation

This article aims at modeling the impact of road characteristics and local spatial environment on road (un)safety. The study applies to Belgium where some 1500 people are killed annually on the roads. This statistic corresponds to one of the highest risks in Europe. Road unsafety is expressed here as whether an hectometer of road belongs to a black zone; a black zone is defined as a segment of road where roads accidents are concentrated. Logistic modeling including spatial autocorrelation is used and compared to non-spatial regression. It is shown that a spatial model is needed to avoid biased estimated parameters. Results show that local environment and road infrastructure play a substantial role in the co-occurrence of road accidents. Hence, education and enforcement cannot be the only measures taken to reach a sustainable road safety. To attain their objectives of accident reduction, public authorities should also take their responsibilities in the matter of securing road infrastructure.