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Superconducting cables can be used to transport large amounts of energy with small losses in considerably smaller volume compared to conventional cables. At present, the first YBCO cable demonstrations are under development and they are expected to outperform BSCCO cables. Due to extremely high current densities in very thin superconducting films these cables are sensitive to overcurrents and therefore cable designers should be able to predict their behaviour during faults. In this paper, the temperature distribution in various 1 kA YBCO cable geometries was computed with several fault current waveforms in order to study the cable stability. FEM models were used to determine simultaneously both the current density and the temperature distributions of the cable as functions of time. Real temperature dependent properties of the cable materials and the strong magnetic field and current density dependence of the superconductor resistivity were taken into account.

In this paper a 30 m long one-phase coaxial YBCO cable with 1 kA transport current and 10 kV operating voltage was designed for the Super3C project to check the feasibility of YBCO tapes for low-loss cables. The final design incorporates cryogenic, mechanical and electromagnetic aspects. The electromagnetic losses during normal operation must be minimized. The cryogenic design must also take into account the generation of heat during short circuit conditions. Mechanical restrictions set the minimum gaps between the coated conductor tapes and the minimum lay angles in order to make the cabling feasible and to enable handling of the cable. The design of the electric insulation should be according to the international standard as far as applicable. The final design has to take into account all of the above restrictions.

Background and Aims: Carotid endarterectomies (CEA) should, by general agreement, be performed only at specialised institutions and on patients who are expected to have a low rate of complications, i.e., a 6% surgical risk for patients with symptomatic and a 3% risk for patients with asymptomatic carotid artery disease. We have reviewed the midterm results after CEA in amedium-sized Finnish central hospital to audit whether our results fulfil current quality standards.Patients, Materials and Methods: There were 116 consecutively operated patients at the Päijät-Häme Central Hospital during the years 1999–2003 on whom 122 CEAs were made. All CEAs were performed by conventional methods and shunts and patches were used when necessary.Results: The overall survival rate was 81.0% during the 3.6 ± 1.5 years [range 1.3–6.3 years] follow-up. The incidence of early major stroke was 2.5% and of late major stroke 1.6%. Other complications included cranial nerve deficit (2.5%), wound haematoma (3.3%) and postoperative hypertension (3.3%) or hypotension (2.5%). Significant changes in medication were needed after surgery in several patient subgroups.Conclusions: The results of CEA at the Päijät-Häme Central Hospital are at least acceptable. The primary prevention of strokes with pharmacotherapy needs aggressive improvement.

During the last five years, the AC performance of high temperature superconductor (HTS) tapes has been under intense development due to the needs of practical applications. Previously, a system capable of measuring time dependent, spatial distribution of the magnetic flux density at a selected distance above the HTS tape has been presented. The tape can carry any cyclic current signal in the frequency range of 0-400 Hz. In this paper, a calculation model to extract information about the current densities, which create the measured magnetic flux density, is developed and used to interpret these measurements. Discrete Fourier transformation is found to provide a numerically stable method that is well suited to the interpretation of results and also for the signal noise exclusion. The third harmonic of the measured Hall voltage is seen to play an integral role in the comparison of the penetration models.

Magneto-optical (MO) imaging, Hall probe measurements and the magnetic knife method were used for sample quality studies of multi-core Bi-2223/Ag tape with a columnar 60-filament structure made by the TIRT (tape in rectangular tube) process. While the magneto-optical imaging was made at 25 K and without transport current, Hall probe and magnetic knife measurements were performed for the sample carrying a direct current at 77 K.

A European consortium has progressed towards AC coil, transformer and cable applications made of low AC loss Bi-2223 conductors. Internally assembled ring-bundle-barrier conductors were used in AC coils and an externally assembled conductor was realized for transformer and reactor windings. For the design and optimization of HTS AC coils, a numerical tool for the prediction of AC losses in coils and coil sets had been developed. The demonstrations with air-core coils and iron-core reactors showed that the numerical tool can already be confidently used in the design and optimization of HTS AC coils at nominal operation conditions. A series of three power cable prototypes was manufactured to estimate the influence of optimized low AC loss tapes on the total losses of a cable. In order to estimate the impact of the twist pitch on the losses we also manufactured cables with short and long twist pitches. The advantages and drawbacks of low AC loss tapes in power applications are discussed on the grounds of the test results.

A European consortium has progressed towards elementary and assembled conductors viable for AC applications in the project ACropolis. The main goal was to achieve low AC losses and high critical current densities in tapes developed for AC coils, transformers and cables. In order to verify the performance of tapes an extensive characterization programme was carried out. The dependence of critical current and AC losses on the parameters of the tape manufacturing process were scrutinized. Furthermore, SEM-EDX and DTA/TG analyses were performed to study the material microstructure, and the diffusion coefficient of oxygen through different matrix metals was measured. The homogeneity of the tapes was verified with magnetic knife and Hall sensor experiments. Transport current measurements were performed at different mechanical stress conditions and also the distribution of critical current along long tapes was determined with a quasi-continuous four-point measurement. The results confirmed that the low AC loss conductors can be produced on an industrial scale and they are competitive in power engineering applications.

Mathematical modeling of gas−solid reactions is very common in chemical engineering, but liquid−solid reactions have received much less attention. Modeling of liquid−solid reactions is not studied very much, but it is gaining importance because the principles of chemical reaction engineering have made a breakthrough in industries dealing with fine and specialty chemicals. General principles for the modeling of complex organic liquid−solid reaction systems in backmixed batch and semibatch reactors are presented. The ingredients of the model are complex kinetics, interfacial mass transfer, and models for solid particles and the reactor. Previously developed theories for solid particles, such as shrinking-particle and porous-particle models, can be applied on liquid−solid systems, but the kinetics is complex and the reactions are carried out (semi)batchwise, which implies that numerical solution algorithms are used. The approach is illustrated with two experimental case studies representing shrinking and porous particles, Claisen condensation and carboxyalkylation of cellulose. Following the modeling principles, it was possible to describe the experimental data very well and predict the behavior of solid particles and the reactor performance. Detailed modeling of the liquid−solid reactions will be used extensively in process scale-up in the future.

We have developed a mathematical model, which enables us to predict the voltage–current V(I) characteristics of a solenoidal high-temperature superconductor (HTS) magnet subjected to an external magnetic field parallel to the magnet axis. The model takes into account the anisotropy in the critical current–magnetic field (I_c(B)) characteristic and the n-value of Bi(2223)Ag multifilamentary tape at 20 K. From the power law between the electric field and the ratio of the operating and critical currents, the voltage on the magnet terminals is calculated by integrating the contributions of individual turns. The critical current of each turn, at given values of operating current and external magnetic field, is obtained by simple linear interpolation between the two suitable points of the I_c(B) characteristic, which corresponds to the angle α between the vector of the resulting magnetic flux density and the broad tape face. In fact, the model is valid for any value and orientation of external magnetic field, and is only limited by the validity of the electric field power law as a function of operating current. Electric fields of individual turns of the model magnet, which consists of 22 pancake coils, have been analysed for different values of operating current and external magnetic field. The voltage distribution on individual pancake coils and the overall voltage between the magnet terminals have also been analysed. Finally, the influence of external magnetic field on the V(I) characteristics of the magnet have been studied for different values of operating current. We report on a new and rather unexpected behaviour of the HTS magnets at different operating conditions, together with a theoretical explanation.

To examine the relationship between the frequency of nightmares and the risk of suicide.

Several organic liquid-phase reactions are carried out in the presence of a sparingly soluble reactive solid phase which is gradually dissolved during the course of the reaction. The presence of the reactive solid phase complicates the treatment of kinetic data, since the overall reaction rate is influenced by the solubility equilibrium and mass transfer rate of the solid compound. A mathematical model has been derived for an organic reaction system with one reactive solid compound. The modelling concept was applied on a linear multistep reaction system, Claisen condensation. The solubility of the solid compound was measured with batch experiments carried out under nonreactive conditions, and the kinetic parameters for the reaction system were determined from the data obtained by semibatch experiments. Model simulations clarified the behavior of the sparingly soluble reactive compound in the process, indicating that the rate equations describe well the experimental kinetic data.

Cyclosporin A (CsA) is a highly hydrophobic drug used to prevent graft rejection after organ transplantation. Interactions of CsA with phosphatidylcholine as well as with binary mixtures containing phosphatidylcholine and cholesterol were investigated by measuring the penetration of CsA into lipid monolayers at an air/water interface, by differential scanning calorimetry, and by imaging with fluorescence microscopy the effects of CsA on the lateral distribution of a fluorescent probe, 1-palmitoyl-2-(N-4-nitrobenz-2-oxa-1, 3-diazol)aminocaproyl-phosphocholine, in monolayers. Film penetration studies revealed the association of CsA with lipids to be a biphasic process. Cholesterol diminished the intercalation of CsA into the monolayer at surface pressures of >19 mN/m. CsA broadened the main transition of dimyristoylphosphatidylcholine (DMPC)/beta-cholesterol (10:1, mol/mol) multilamellar vesicles. The behavior of the transition enthalpy was more complex; the behavior of DMPC/beta-cholesterol multilamellar vesicles in the XCsA of 0 to 0.1 showed at most ratios a increase, but several well distinct dips were observed. The results are interpreted in terms of regular structures in tertiary alloy. Influence of CsA on lateral organization could be verified for lipid domains observed by fluorescence microscopy of lipid monolayers. More specifically, CsA altered the distribution of 1-palmitoyl-2-(N-4-nitrobenz-2-oxa-1, 3-diazol)aminocaproyl-phosphocholine in a dipalmitoylphosphatidylcholine film and in DPPC/beta-cholesterol (88:10, mol/mol) mixtures in a manner that suggests that CsA partitions into the boundaries between fluid and gel domains. To our knowledge, this constitutes the first demonstration of a change in lipid domain morphology to be induced by a drug molecule.

The carboxyl-terminal cytoplasmic domain of the angiotensin II type 1 (AT1) receptor has recently been shown to interact with several classes of cytoplasmic proteins that regulate different aspects of AT1 receptor physiology. Employing yeast two-hybrid screening of a mouse kidney cDNA library with the carboxyl-terminal cytoplasmic domain of the murine AT1a receptor as a bait, we have isolated a novel protein with a predicted molecular mass of 18 kDa, which we have named ATRAP (for AT1 receptor-associated protein). ATRAP interacts specifically with the carboxyl-terminal domain of the AT1a receptor but not with those of angiotensin II type 2 (AT2), m3 muscarinic acetylcholine, bradykinin B2, endothelin B, and beta2-adrenergic receptors. The mRNA of ATRAP was abundantly expressed in kidney, heart, and testis but was poorly expressed in lung, liver, spleen, and brain. The ATRAP-AT1a receptor association was confirmed by affinity chromatography, by specific co-immunoprecipitation of the two proteins, and by fluorescence microscopy, showing co-localization of these proteins in intact cells. Overexpression of ATRAP in COS-7 cells caused a marked inhibition of AT1a receptor-mediated activation of phospholipase C without affecting m3 receptor-mediated activation. In conclusion, we have isolated a novel protein that interacts specifically with the carboxyl-terminal cytoplasmic domain of the AT1a receptor and affects AT1a receptor signaling.

This study examines the role of sphingolipids in mediating the apoptosis of PC12W cells induced by the angiotensin II type 2 (AT2) receptor. PC12W cells express abundant AT2 receptor but not angiotensin II type 1 receptor and undergo apoptosis when stimulated by angiotensin II. AT2 receptor-induced ceramide accumulation preceded the onset of caspase 3 activation and DNA fragmentation. AT2 receptor-induced ceramide accumulation did not result from the degradation of complex sphingolipids (SL) such as sphingomyelin or glycosphingolipids, as no changes in neutral or acidic sphingomyelinase activities, sphingomyelin level, nor in cellular glycolipid composition were observed. AT2 receptor activated serine palmitoyltransferase with a maximum time of 24 h after angiotensin II stimulation. The AT2 receptor-induced accumulation of ceramide was blocked by inhibitors of the de novo pathway of SL synthesis, beta-chloro-L-alanine and fumonisin B1. Inhibition of the de novo biosynthesis of SLs by fumonisin B1 and beta-chloro-L-alanine completely abrogated the AT2 receptor-mediated apoptosis. Pertussis toxin and orthovanadate blocked AT2 receptor-mediated ceramide production. Taken together our data demonstrate that in PC12W cells the stimulation of AT2 receptor induces the activation of de novo pathway, and a metabolite of this pathway, possibly ceramide, mediates AT2 receptor-induced apoptosis.

A kinetic model for the reductive alkylation of aromatic amines, which implies a combination of homogeneous and heterogeneous reactions, was developed. The kinetic model was combined with a reactor model for a semibatch reactor, traditionally used for the reductive alkylation on both laboratory and industrial scale. The system was modelled as a three-phase system, with mass-transfer limitations at the gas−liquid interface. The mass-transfer resistances at the outer surface of the catalyst and inside the catalyst were considered to be negligible, since very finely dispersed catalyst particles were used. The kinetic parameters were determined for a system containing an aromatic amine with one alkyl substituent and an aldehyde. The results revealed that it is possible to describe this kind of complex reaction system with very few parameters.

A generally applicable stoichiometric and kinetic model was developed for the polyesterification of unsaturated dicarboxylic acid with diols in the presence of a homogeneous acid catalyst. The model also incorporates, besides the esterification, the cis−trans isomerization and the double-bond saturation reactions. Rate equations based on plausible mechanistic reaction steps were derived, and the parameters of the rate equations were determined with nonlinear regression analysis using the polyesterification of maleic acid with propylene glycol at 150−190 °C as a demonstration system. Comparisons of the model predictions with the experimental data showed that the approach is useful in predicting the polyesterification kinetics and the product distribution.

Objective:: To assess the validity of a national vascular registry. Materials and methods:: 17 465 vascular and endovascular procedures, immediate reoperations excluded, registered in the Finnvasc registry from 26 centres during the years 1991-1994. Chief outcome measures:: Comparison of the number of registered procedures with hospital records, comparison of initial registrations with a random sample of re-registration and comparison of the 1-year local data input of one major centre to the same data input of the central unit. Results:: The rate of missing registrations was 19% ranging from 0-47%. The data of the re-registered forms were in agreement with the original data in 93% of all data points, the range being from 81-100%. There was a difference of 1.5% in the data between the major centre and the central unit. Conclusions:: The Finnvasc registry makes it possible to audit vascular surgery nationally, although a potential limitation is centres with low registration rates.

Optimization of the reaction conditions in liquid phase semibatch reactors where several complex reactions simultaneously take place was studied. The optimization procedure was demonstrated with the production of substituted alkyl phenols from aromatic sulfonic acid via alkali fusion. The reagent, the substituted aromatic sulfonic acid, participates in the main reaction and in several side reactions, such as the elimination of the alkyl, the amino, and the sulfonic acid groups as well as polymerization reactions. The kinetics was determined for the reaction system, on the basis of the laboratory scale batch reactor experiments. The kinetic model was combined with a large scale reactor model, where not only the feed of the reactant but also the precipitation and volatilization of some reacting compounds were considered. It turned out that an extrapolation from the 0.1 dm³ laboratory reactor to the 10 m³ large scale was very successful. The reaction conditions of industrial scale semibatch reactor were optimized using the desirability function approach, which combines the desired conversion of the reagent, the desired selectivity of the product, and the reaction time. The qualities of different desirability functions were compared. The great benefit of the desirability approach is that it provides smooth objective functions, avoiding a cumbersome constrained optimization.

Objective: To determine whether nursing influences brain activity in the newborn and whether there are differences in this respect between breast- or bottle-feeding and pacifier sucking. Study Design: Fifty unselected volunteer mothers and their healthy full-term infants, under care in the maternity ward after delivery, served as subjects. Thirty mother-infant pairs were studied in relation to breast-feeding and 20 to bottle-feeding and pacifier sucking. Breast-fed infants were studied between the 1st and 7th day after delivery (mean +/- 2.7 days) and the infants in the bottle-fed group between the 1st and 8th day after delivery (mean +/- 3.3 days). Methods: Qualitative and quantitative electroencephalogram (EEG), electro-oculogram, submental electromyogram, and electrocardiogram were recorded before, during and after breast- and bottle-feeding and pacifier sucking. Results: The amplitude of the EEG increased significantly during breast-feeding in the posterior cortical areas in both hemispheres with a slight predominance on the right. Bottle- feeding caused a similar, but somewhat less marked change. When the breast- and bottle-fed infants were compared, a significant difference was found in only one parameter of the 84 studied. Pacifier sucking had no significant effects on EEG activity. Conclusion: Nursing effects a change in the brain activity of the newborn. The cortical response to nursing is most probably a result of activation of the neurohumoral mechanisms related to hunger and satisfaction, including the hypothalamic, limbic, and other brain stem structures, which also regulate the sleep-wake cycle and modulate the level of cortical activity with respect to attention and vigilance. (J Pediatr 1998;132:646-51.)

Earlier research has implicated coffee drinking as a possible protective factor for suicide. We followed-up 43,166 subjects for the mean 14.6 years, and 213 suicides were committed. Daily coffee drinking had a J-shaped association with the risk of suicide. Using the Cox model we controlled for potential covariates, and found that among heavy coffee drinkers (≥ 8 cups/day) the risk of suicide was 58% higher compared with more moderate drinkers.