Effect of dietary selenium on the progression of heart failure in the ageing spontaneously hypertensive rat

Oxidative stress has been directly implicated in hypertension and myocardial remodelling, two pathologies fundamental to the development of chronic heart failure. Selenium (Se) can act directly and indirectly as an antioxidant and a lowered Se status leads to a higher risk of cardiovascular disease. This study examined the role of Se on the development of hypertension and subsequent progression to chronic heart failure in spontaneously hypertensive rats (SHR). Three dietary groups were studied: (i) Se‐free; (ii) normal Se (50 μg Se/kg food); and (iii) high Se (1000 μg Se/kg food). Systolic blood pressure and echocardiography were used to detect cardiac changes in vivo. At study end, cardiac tissues were assayed for glutathione peroxidase activity, thioredoxin reductase activity, and protein carbonyls. The major finding of this study was the high heart failure‐related mortality rate in SHRs fed an Se‐free diet (70%). Normal and high levels of dietary Se resulted in higher survival rates of 78 and 100%, respectively. Furthermore, high dietary Se was clearly associated with lower levels of cardiac oxidative damage and increased antioxidant expression, as well as a reduction in disease severity and mortality in the SHR.     

Time-optimal velocity planning along predefined path for static formations of mobile robots

International Journal of Control, Automation and Systems - This paper is concerned with the problem of finding a time-optimal velocity profile along the predefined path for static formations of...     

A microdosimetry chamber for low-energy X rays

A wall-less proportional counter designed to measure single event spectra produced by low energy X rays is described. The sensitive volume of the counter and the housing are made entirely of non-metallic materials to minimise distortions in the secondary electron spectrum.     

A nonlinear tracking control for sensorless induction motors

We propose a novel tracking control for induction motors in which only stator currents are used for feedback. Local exponential rotor speed and flux modulus tracking are achieved for any constant reference value and for restricted time-varying reference signals; any known motor parameters values (including constant load torque) and any initial condition, including rotor speed and fluxes, belonging to an explicitly computed domain of attraction are allowed.     

Expression of multidrug resistance (mdr) gene(s) in primary lymphoid organs of chicken immune system during embryonic development

The present study investigated the processing of painful electrical stimuli in patients with unilateral frontal or parietal lobe damage and matched control subjects. Patients with frontal lesions showed increased pain thresholds when the stimuli were administered contralateral to the lesion. While the peak-to-peak amplitudes of the N150/P250 components of the somatosensory potentials increased linearly with stimulus intensity in the control subjects, the responses in the frontal group did not change significantly between stimulation at pain and tolerance threshold. There was no evidence for altered pain processing in patients with parietal lobe lesions. The findings of the present study support the hypothesis of an involvement of the frontal cortex in pain perception in humans.     

Cisapride in neurologically impaired children with chronic constipation

The efficacy of cisapride as a treatment for chronic constipation in children with severe brain damage was studied in 20 children. Each subject was randomly assigned to double-blind treatment with either cisapride (N = 10) or placebo (N = 10) for 12 weeks. Stool habits, total gastrointestinal transit time, colonic segmental transit times, and anorectal motility were evaluated in all children before and at the end of the treatment period. Although cisapride significantly (P < 0.05) increased stool frequency from baseline to week 12 and no significant change was documented in the placebo group, the mean change in stool frequency per week from baseline to 12 week was not significantly different between the two treatment groups. The use of laxatives or suppositories was significantly (P < 0.05) decreased by cisapride, but remained unchanged in the placebo group. Furthermore, cisapride significantly (P < 0.05) reduced rectal compliance but had no effect on total gastrointestinal transit time and colonic segmental transit times. In summary, in neurologically impaired children with chronic constipation, cisapride increased bowel frequency but did not alter the delay in total and segmental gastrointestinal transit times.     

Hamiltonian-type Lyapunov functions

A flexible and systematic way for the construction of Lyapunov functions which lends itself to the use of nonlinear programming techniques is presented. The class of Lyapunov functions obtained is shown to be energy functions (Hamiltonians) for an equivalent system.     

Laplace Plane Analysis of Transient Impedance Between Acupuncture Points Li-4 and Li-12

AC impedance between two acupuncture points (Li-4 and Li-12) and two pairs of anatomically similar points with the same separation was studied via Laplace plane analysis of the time domain current response to a predetermined voltage perturbation. The series resistance between the two acupuncture points was found to be significantly lower than between either pair of control points. The characteristic impedance of an equivalent transmission line was lower and the signal propagation velocity higher for the acupuncture point system as compared to both controls.     

Ventilation effects on air quality and on the yield and quality of ewe milk in winter

The effects of ventilation on air quality, and on the welfare and production performance of dairy ewes were assessed in a 6-wk trial conducted during the winter of 2002. Thirty-six midlactation Comisana ewes were divided into three groups of 12, which were randomly balanced for parity, time of lambing, and number of lambs suckled. Treatments were low (LOV), moderate (MOV), and programmed ventilation regimen (PROV). In LOV and MOV rooms, fans provided 10 ventilation cycles of 40 min each at a fan speed of 1 and 2 m/s, respectively. In the PROV room, the fan was programmed to maintain a 70% relative humidity. Mean ventilation rates were 23, 47, and 73 m3/h per ewe in LOV, MOV, and PROV rooms, respectively. Air concentrations of microorganisms and dust, and of gaseous pollutants were measured twice weekly. Cell-mediated immune response to phytohemagglutinin at d 1, 21 and 42, and humoral response to chicken egg albumin at d 11, 21, 30, and 40 were determined. At d 39, ewes were injected with 2 IU of porcine adreno-corticotropic-hormone/kg body weight(0.75), and subjected to blood sampling for evaluation of cortisol concentrations immediately before and 1, 2, and 4 h after adreno-corticotrophic-hormone injection. Milk yield was recorded daily. Individual milk samples were analyzed weekly for composition, renneting parameters, and somatic cell count. The LOV treatment resulted in higher air concentrations of NH3 and CO2 than the MOV and PROV treatments. Greater amounts of total and respirable dust were found in the PROV room than in the LOV and the MOV rooms. The LOV ewes had lower milk yield than the PROV ewes, lower milk casein content, and higher rate of clot formation than the MOV and PROV ewes. The ventilation regimen did not affect the immune and endocrine responses of the ewes. Results suggest that an intermittent ventilation regimen, providing a mean ventilation rate of 47 m3/h per ewe at a fan speed of 2 m/s, is required to sustain the yield and cheese-making ability of ewe milk during the winter season.     

A Real-Time Visual Inspection System for Railway Maintenance: Automatic Hexagonal-Headed Bolts Detection

Rail inspection is a very important task in railway maintenance, and it is periodically needed for preventing dangerous situations. Inspection is operated manually by trained human operator walking along the track searching for visual anomalies. This monitoring is unacceptable for slowness and lack of objectivity, as the results are related to the ability of the observer to recognize critical situations. The correspondence presents a patent-pending real-time Visual Inspection System for Railway (VISyR) maintenance, and describes how presence/absence of the fastening bolts that fix the rails to the sleepers is automatically detected. VISyR acquires images from a digital line-scan camera. Data are simultaneously preprocessed according to two discrete wavelet transforms, and then provided to two multilayer perceptron neural classifiers (MLPNCs). The "cross validation" of these MLPNCs avoids (practically-at-all) false positives, and reveals the presence/absence of the fastening bolts with an accuracy of 99.6% in detecting visible bolts and of 95% in detecting missing bolts. A field-programmable gate array-based architecture performs these tasks in 8.09 mus, allowing an on-the-fly analysis of a video sequence acquired at 200 km/h