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Density peaking has been studied between an ICRH and NBI identity plasma in JET. The comparison shows that 8 MW of NBI heating/fueling increases the density peaking by a factor of two, being R/L n = 0.45 for the ICRH pulse and R/L n = 0.93 for the NBI one averaged radially over ρ tor = 0.4, 0.8. The dimensionless profiles of q, ρ *, υ *, β n and T i/T e ≈ 1 were matched within 5% difference except in the central part of the plasma (ρ tor < 0.3). The difference in the curvature pinch (same q-profile) and thermo-pinch (T i = T e) between the ICRH and NBI discharges is virtually zero. Both the gyro-kinetic simulations and integrated modelling strongly support the experimental result where the NBI fuelling is the main contributor to the density peaking for this identity pair. It is to be noted here that the integrated modeling does not reproduce the measured electron density profiles, but approximately reproduces the difference in the density profiles between the ICRH and NBI discharge. Based on these modelling results and the analyses, the differences between the two pulses in impurities, fast ions (FIs), toroidal rotation and radiation do not cause any such changes in the background transport that would invalidate the experimental result where the NBI fuelling is the main contributor to the density peaking. This result of R/L n increasing by a factor of 2 per 8 MW of NBI power is valid for the ion temperature gradient dominated low power H-mode plasmas. However, some of the physics processes influencing particle transport, like rotation, turbulence and FI content scale with power, and therefore, the simple scaling on the role of the NBI fuelling in JET is not necessarily the same under higher power conditions or in larger devices.

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Core density profile peaking and electron particle transport have been extensively studied by performing several dimensionally matched collisionality (?*) scans in various plasma operation scenarios on JET and on DIII-D and a 2-point ?*scan in I-mode on C-Mod. The experimental results from the various JET H-mode as well as the DIII-D H-mode scans show that density peaking increases with decreasing ?*. In JET, the NBI particle source is contributing 50-60% to the peaking in plasmas where Te/Ti~1 and at ?*=0.1-0.5 (averaged between r/a=0.3-0.8) independent of ?*. On DIII-D, the density peaking is solely a transport effect at low ?* while the NBI contributes to density peaking around 30-40% at higher ?*. The reason for JET and DIII-D being different with respect to NBI fueling versus inward pinch is under investigation. These dimensionally matched ?* scans give the best data for model validation. TGLF simulations are in excellent agreement with the experimental results with respect to the role of NBI versus inward pinch in JET and higher ?* discharges on DIII-D. GENE predicts larger role for the NBI fueling in JET than observed in experiment but is in good agreement within the DIII-D scan, justifying the use of these models/codes in predicting density peaking. In L-mode plasma conditions, the role of the NBI source is small, typically 10-20% and the electron particle transport coefficients are large. On C-Mod, the I-mode density peaking database indicated that in the I-mode plasmas, there is no ?* dependence in density peaking. This result indicates that particle transport characteristics are more analogous to those of L-mode than H-mode and similar to L-mode ones observed in JET and DIII-D.

Particle transport in tokamaks has received much less attention than electron and ion heat transport channels. It is still often not treated self-consistently in transport modelling and predictions for future tokamaks. As a consequence, particle transport and fuelling remain one of the major open questions in understanding the ITER physics [1]. The shape of the density profile has a significant influence on fusion performance and impurity transport. Particle transport has been extensively studied by performing several dimensionally matched collisionality scans in various plasma scenarios in JET. Gas puff modulation technique has been developed with high quality time-dependent density profile measurements to determine particle transport coefficients on JET [2]. The local electron density response to the gas injection was measured Thomson scattering diagnostics close to the midplane. Modulation amplitudes below 0.3-0.5% at mid-radius are reliably measured thus allowing minimal plasma disturbance and the possibility to use data from multiple harmonics. The gas puff modulation was performed with a gas valve at the top of the machine at 3Hz frequency using rectangular waveform, the rate varying from 0 to 6x1022 s-1 at 30% duty cycle. 2. Dimensionless

SUMMARY When fiber optic probes were taken into use to record local hot-spots in windings and oil ducts, it was noticed that the hot-spot temperature rise over top-oil temperature due to load changes is a function depending on time as well as the transformer loading (overshoot time dependent function). This results in winding hottest spot temperatures higher than those predicted by the old loading guide during transient states after the load current increases, before the corresponding steady states have been reached. The new loading guide, (IEC 60076–7), takes into account these findings by introducing two thermal models. The first one, which is given as an exponential equation solution, is suitable for a load variation according to a step function. This method is particularly suited to determination of the heat transfer parameters by test, especially by manufacturers. The second one, which is given as a differential equations solution, is suitable for arbitrarily time-varying load factor K and time-varying ambient temperature θa. This method is particularly applicable for on-line monitoring. This method is a mathematical variation of the exponential model. A significant advantage of the suggested thermal models is that they are tied to measured parameters that are readily available (i.e., data obtained from a non-truncated heat run test performed by the transformer manufacturer). However, it has been reported recently by many users that this new approach causes a lot of technical hitches. It is unclear when and why the exponential method should be used instead of or the differential method and vice versa. Also, is there any difference between the recommended models, especially in their output? How the new thermal constants, (k11, k21, and k22), should be applied and how they could be derived? Answers to these questions and more are given in the text below. Copyright © 2012 John Wiley & Sons, Ltd.

A simple model for calculating the hot-spot temperature is introduced. The model is based on the hot-spot to ambient gradient. The model considers the changes of the oil viscosity and winding losses with temperature. The results are compared with temperatures calculated by IEEE Annex G method and measured results at varying load for the following transformer units: 250-MVA ONAF, 400-MVA ONAF, and 605-MVA OFAF.

The second Jack Pepys Workshop on Occupational Asthma was held in Toronto, Canada, in May 2004. The present report summarises key questions and research needs as identified by the international participants. The audiotapes from the workshop discussions were summarised by the organising chairs of the Symposium and the resulting document was circulated for input from all invited workshop participants. In total, 100 key questions and research needs were identified. Identified needs included: provision of different definitions depending on the use of data; explanations for differences in frequency studies; and better characterisation of genetic and environmental determinants of occupational asthma. The role of irritants and the pathogenesis of various forms of work-related asthma need further research, and there are also questions and research needs for diagnosis, prevention and understanding of persistence and airway remodelling. In conclusion, although advances have been made in the understanding of occupational asthma and other work-related asthma, further key issues remain that need addressing.

Comprehensive load/thermal testing was performed on a 400/400/125 MVA, ONAF-cooled transformer. It was shown that the local hot-spots in the windings, core, and structural parts rise much faster at load increase than what an exponential function based on the time constant of top oil would predict. This paper analyzes these fast rises more in detail for hot-spots in windings, core, yoke clamps, and tie plates. An alternative mathematical model of the winding hot-spot response is presented. Different cooling modes, like ONAF and OFAF, are dealt with. Also different modes of oil circulation through the windings, in horizontal (zig-zag) or axial cooling ducts, are compared. The results are verified by fiberoptic installations and tests on several large power transformers in the range of 250 - 650 MVA. Hot-spot responses predicted by the IEEE Loading Guide, Annex G, are also compared to measured values.

Comprehensive load /thermal testing was performed on a 400/400/125-MVA transformer representing a new design generation for large power transformers with a short time emergency loadability of 2.5 p.u. This particular overloadability factor required special design features to control the very high leakage flux resulting from such a loading condition and hence ensure that the transformer satisfies existing standards limits on hot-spot. This paper presents these design features along with a description of a full-size transformer which was built for the sake of developing these flux control measures. Hot-spot temperature measurements in the windings and in the outer core packets and structural parts under a number of overloading conditions are presented and discussed. The results confirm the soundness of the design to handle the 2.5-p.u. overloadability while satisfying the hot-spot requirement according to the existing loading guides for 1.5-p.u. overloading. The measurements also show that the hot-spots will rise much faster than what an exponential function based on the time constant of top oil would predict.

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Particle transport due to Ion Temperature Gradient/Trapped Electron (ITG/TE) mode turbulence is investigated using the gyrokinetic code GENE. Both a reduced quasilinear (QL) treatment and nonlinear (NL) simulations are performed for typical tokamak parameters corresponding to ITG dominated turbulence. A selfconsistent treatment is used, where the stationary local profiles are calculated corresponding to zero particle flux simultaneously for electrons and trace impurities. The scaling of the stationary profiles with magnetic shear, safety factor, electron-to-ion temperature ratio, collisionality, toroidal sheared rotation, triangularity, and elongation is investigated. In addition, the effect of different main ion mass on the zero flux condition is discussed. The electron density gradient can significantly affect the stationary impurity profile scaling. It is therefore expected, that a selfconsistent treatment will yield results more comparable to experimental results for parameter scans where the stationary background density profile is sensitive. This is shown to be the case in scans over magnetic shear, collisionality, elongation, and temperature ratio, for which the simultaneous zero flux electron and impurity profiles are calculated. A slight asymmetry between hydrogen, deuterium and tritium with respect to profile peaking is obtained, in particular for scans in collisionality and temperature ratio., Comment: 18 pages, 10 figures, submitted to Physics of Plasmas

The effects of finite on the toroidal ion temperature gradient mode has been investigated by a multi-pole fluid model. Experimental data from the Joint European Torus (JET) have been used to ensure the relevance to experiments. The mode is strongly stabilized by finite- effects well below the MHD ballooning mode stability threshold.

OBJECTIVES: Hairdressers are exposed to many irritative and allergenic substances capable of causing occupational respiratory symptoms and diseases. The self reported prevalence of respiratory symptoms and diseases was studied, and the risks among hairdressers compared with saleswomen was estimated. METHODS: A cross sectional prevalence study of respiratory symptoms and diseases was carried out among hairdressers and supermarket saleswomen, with a computer assisted telephone interview method (CATI). The study population comprised all the female hairdressers and supermarket saleswomen aged 15-54 years in the Helsinki metropolitan area, Finland. Disproportionate random samples of female hairdressers and sales-women were drawn from the trade union membership registers. The interviews were carried out between February and April 1994. A response rate of 80.5% (355/440) was obtained for hairdressers and 82.2% (583/709) for saleswomen. Atopy, smoking, chronic illnesses, type of work, working hours, working conditions, personal and professional use of hair products, and the use of personal protective devices were assessed. The outcome variables were self reported symptoms of the upper and lower respiratory tract. These were used to define chronic bronchitis, and asthma, laryngitis, and allergic rhinitis diagnosed by a physician. RESULTS: There was a considerable difference in the prevalence of chronic bronchitis; 6.8% in hairdressers versus 1.9% in saleswomen. The odds ratio (OR) adjusted for age, smoking, and atopy for chronic bronchitis indicated an increased risk of chronic bronchitis (OR 4.8, 95% confidence interval (95% CI) 2.2 to 10.1). No association was found between work as a hairdresser and asthma, laryngitis, and allergic rhinitis. Also the prevalence of rhinitis, rhinitis with eye symptoms, cough with phlegm, dyspnoea, and dyspnoea accompanied by cough was increased among hairdressers. The corresponding adjusted risk ORs were 1.7 (95% CI 1.3 to 2.3) for rhinitis, 1.9 (95% CI 1.4 to 2.6) for rhinitis with eye symptoms, 1.4 (CI 1.1 to 1.9) for cough with phlegm, 1.5 (95% CI 1.0 to 2.2) for dyspnoea, and 1.6 (95% CI 1.0 to 2.7) for dyspnoea with cough. CONCLUSIONS: Our results indicate an increased prevalence of upper and lower respiratory symptoms among hairdressers. Allergenic and irritative chemicals in hairdressing are likely candidates explaining the difference found between the hairdressers and controls. Work related reasons should be considered when a hairdresser presents with airway symptoms. Preventive actions are needed to improve the working conditions and personal protection.

In the present study, the impact of sheared toroidal rotation on L-mode and H-mode experiments with carbon wall at the Joint European Torus are analysed using the coupling between the transport codes JETTO (for main ions) and SANCO (for impurities) for predictive simulations. Transport coefficients due to Ion-Temperature-Gradient (ITG) mode and Trapped-Electron (TE) mode turbulence are used together with neoclassical transport from NCLASS. The transport coefficients obtained using the Chalmers fluid model, updated with the roto-diffusion associated with sheared rotation, are compared with gyrokinetic results using the code GENE. Self-consistent simulations of electron and ion temperatures, main ion and impurity densities are performed while the toroidal momentum profile is treated interpretatively. The role of neoclassical impurity transport is evaluated and the dependence of the simulated profiles on impurity charge number Z, rotation gradient (roto-diffusion), and impurity charge fraction (Zeff) are discussed. In particular the impact of sheared toroidal rotation on the C profiles is investigated. The considered discharges include L-mode impurity injection experiment Pulse No: 67730, as well as a H-mode discharge. The impurity behaviour in the L-mode and H-mode discharges are compared, however, experimental data for the impurity transport coefficients are only available for the L-mode discharge.

Disease registers and surveillance schemes are not necessarily designed to measure incidence and prevalence, but their data can provide useful epidemiological insights. Their main functions are the detection and identification of hazards so that further cases can be prevented, and to provide a database for research to improve our understanding of the determinants and consequences of disease. Occupational asthma probably accounts for only a small proportion of adult asthma, of the order of 2-6% in the UK. On the other hand, asthma is very common and so thousands of people in the UK and in other western countries have asthma as a result of their work. The frequency of the disease in less developed countries is unknown but is potentially very large. Information on incidence is patchy but from Finland, where ascertainment is most complete, there are approximately 140 per million working people affected each year, and even there disease in the self-employed is probably missed. Data for the UK are limited to cases seen by specialist physicians and the best estimate is that the annual incidence of such cases is about 50 per million. Through internal comparisons and analysis it is possible to judge the extent to which variation in ascertainment and reporting have affected the frequency of reported disease, but so far it has not been possible to measure the underestimation due to persons with work-related symptoms not seeking medical attention or not being referred to a specialist.

The stability of electromagnetic ballooning modes is investigated using a toroidal two‐fluid model allowing for arbitrary Ln/LB (the characteristic scale lengths of density and magnetic‐field inhomogeneities). The ballooning mode equation is solved numerically and the two‐fluid and magnetohydrodynamic stability properties are discussed and compared. The perpendicular compressibility strongly reduces the growth rate and for Ln/LB∼Ln/LT∼1, the mode is completely stabilized.

In recent experiments on TFTR the concept of marginal stability for ion temperature gradient driven modes was tested by pellet fuelling which strongly increased ηi = Ln/LTi. Such a shot was studied with a fluid transport model and it was found that, as in the experiment, the maximum χi does not increase. This is due to stabilizing effects of compressibility and nonadiabaticity

The anomalous transport and turbulence driven by a combination of the toroidal ion temperature gradient (ITG) mode and dissipative trapped electron (DTE) mode are studied for a plasma in the dissipative regime. The results from numerical mode coupling simulations show a good agreement with the results from quasilinear theory. A transition from the neo-Alcator scaling of the energy confinement time with density to a saturated state is obtained. It is shown that ion heat pinch effects (inward transport) may exist in the process of thermodynamic relaxation of the system.

The effects of an impurity ion species on the linear stability of the toroidal ion temperature gradient driven mode (ηi mode) are investigated together with the scaling properties of the corresponding quasi-linear transport coefficients. A stabilizing influence of impurities is found for inwardly peaked or flat impurity density profiles except for small n (n = 2Ln/LB), in which case destabilization is found. However, new impurity driven instabilities are introduced also below the pure ηi mode stability threshold. The ηi mode still accounts for the major part of the quasi-linear ion energy transport, which is reduced accordingly. The direction of the ion particle transport is mainly determined by the shape of the the impurity density profile in relation to the background ion profile. With an inwardly peaked impurity profile, the impurity flow is usually directed towards the edge and the main ion flow is reversed owing to ambipolarity

Simulation results of toroidal ${\mathrm{\ensuremath{\eta}}}_{\mathit{i}}$-mode turbulence are analyzed using mathematical tools of nonlinear dynamics. Low-dimensional chaotic attractors are found in the strongly nonlinear regime while in the weakly interacting regime the dynamics is high dimensional. In both regimes, the solutions are found to display sensitive dependence on initial conditions, characterized by a positive largest Liapunov exponent.

A fluid model which includes impurity ions is used to study the particle diffusion due to ηi -modes in a toroidally confined plasma. The diffusion coefficients are derived by quasi-linear theory. The diffusion of the main ion species, which in the present system is nonzero only due to the presence of impurities, may be directed inwards for a negative radial impurity ion density gradient or, under special conditions, for a flat or a positive gradient. In the latter case the impurity ion temperature must have a faster radial variation than the main ion temperature. In the typical case, the impurity concentration and charge usually tend to increase the magnitude of the particle transport in the studied region.

Self-consistent transport code simulations have been performed for a system of temperature gradient driven toroidal drift modes using a fluid model valid for arbitrary Ln/LB. Both an L-mode scaling for low heating power and transitions to enhanced confinement regimes for higher heating power have been obtained. In the enhanced confinement regime, a state with typically χe > χi develops.

The use of non-linear (solid state) loads in power system has increased the awareness of the potential reduction of a transformer life due to the increased losses. Manufacturers and users have been applying IEEE C57.110-1989 which gives a conservative estimate of loading capability of transformers. In this paper, the effect of harmonics on transformers is discussed and a thermal model to predict a transformer hot spot temperature is presented. The model considers a time varying harmonic load cycle and ambient temperature. The model is applied on 31.5 MVA, 115/spl times/9/spl times/1.67%/6.3 kV ONAF transformer.

This paper presents a thermal model of a power transformer in the form of simple equivalent circuit. The model is established to calculate the top oil and hot spot temperatures. The model parameters are obtained from manufacturer test data and an electromagnetic analysis using finite element method (FEM). The model results are compared with measured data obtained from 250 MVA, 230/spl plusmn/8/spl times/1.5%/118/21 kV ONAF transformer equipped with fiber optic probes and tested according to a load cycle comprising a short time load up to 2.1 pu. The results are additionally compared with the conventional equations of the IEEE clause 7.

The assumption that the transformer windings eddy loss rise in proportion to the square of the harmonic order is reasonable for small conductors and low harmonics with errors on the conservative side only for a combination of large conductors and higher harmonics. This paper presents a corrected harmonic loss factor by taking into account the depth of penetration, which leads to more accurate estimation of the increased transformer winding losses under non-sinusoidal load currents.

A comparison between two‐fluid, gyrofluid, and gyrokinetic descriptions of the collisionless ballooning mode in the toroidal limit is performed. The two‐fluid model [A. Jarmen et al., Nucl. Fusion 27, 941 (1987)] is reactive and expanded in the finite‐Larmor radius (FLR), in contrast to the gyrofluid model [R. E. Waltz et al., Phys. Fluids B 4, 3138 (1992)], which is dissipative and includes finite‐Larmor‐radius effects to all orders. The eigenmode differential equation is derived and solved numerically. It is shown that the fluid models are able to reproduce the gyrokinetic result, at least qualitatively. The role of the ion magnetic drift resonance and the ion FLR terms, in the fluid and kinetic descriptions, is discussed.

Over the last two years, several experiments relevant for the study of particle transport and density profile evolution, have been performed at JET. They can be classified as stationary discharges with and without central particle source due to the beams, quasi-stationary discharges with deuterium gas puffing, deep pellet fuelled discharges and discharges perturbed by cold pulses obtained by shallow pellet injection. All these experimental scenarios have been simulated by means of the JETTO transport code, employing different transport models: purely empirical models and the semi-empirical mixed Bohm/gyro-Bohm transport model, both with the addition of different theory-based expressions for the anomalous particle pinch and the first principle Weiland transport model. The coefficients used to scale the pinch velocity in the purely empirical and in the mixed Bohm/gyro-Bohm model have been varied from shot to shot. In this paper, the results of the simulations are presented. The main conclusions are that, for the cases studied in this paper, the sawtooth activity is the main particle transport mechanism in the plasma centre (r/a ≤ 0.5). Nevertheless, to reproduce the density profile in the gradient zone (0.5 ≤ r/a ≤ 0.9), an anomalous pinch seems to be necessary, at least for L-mode plasmas. This anomalous convective flux is well reproduced by the off-diagonal elements of the transport matrix given by the Weiland model.

Particle transport in magnetized plasmas is investigated with a fluid model of drift wave turbulence. An analytical calculation shows that magnetic field curvature and thermodiffusion drive an anomalous pinch. The curvature driven pinch velocity is consistent with the prediction of turbulence equipartition theory. The thermodiffusion flux is found to be directed inward for a small ratio of electron to ion pressure gradient, and it reverses its sign when increasing this ratio. Numerical simulations confirm that a turbulent particle pinch exists. It is mainly driven by curvature for equal ion and electron heat sources. The sign and relative weights of the curvature and thermodiffusion pinches are consistent with the analytical calculation.

Seeding of impurities into JET resulted in a pronounced modification of plasma confinement properties. In order to analyse the underlying mechanisms a predictive transport modelling has been performed by means of two approaches. (i) The Chalmers advanced fluid model for temperature gradient driven instabilities is applied to determine all transport coefficients necessary for transport modelling. In the present code computations the radial profiles of the particle densities and temperatures are computed using experimentally measured sources. The computations give good agreement of the temperature profiles with the measured ones. (ii) The Julich transport model, used earlier to simulate the plasma evolution in TEXTOR radiative improved mode, has been amended by a proper description of trapped electron transport, which is important at low collisionality typical for JET. This model incorporated into the transport code RITM, which self-consistently computes particle sources due to plasma recycling and impurity ionization, reproduces well the peaking in density and pressure profiles caused by impurity seeding.

Stationary inward flows of electron energy have been obtained in transport code simulations of reactive drift wave systems. The recent experimental results with off‐axis electron cyclotron heating in the DIII‐D tokamak [Phys. Rev. Lett. 68, 52 (1992)] have been recovered with peaked electron temperature profiles and strong profile consistency.

Diisocyanates are the most common low molecular weight chemicals to cause occupational asthma. However, only some 5-10% of exposed workers develop asthma, which suggests an underlying genetic susceptibility. Diisocyanates and their metabolites may be conjugated with glutathione by glutathione S-transferases (GSTs). We examined whether polymorphisms in the GSTM1, GSTM3, GSTP1 and GSTT1 genes modify allergic responses to diisocyanate exposure. The study population consisted of 182 diisocyanate exposed workers, 109 diagnosed with diisocyanate-induced asthma and 73 without asthma. Lack of the GSTM1 gene (null genotype) was associated with a 1.89-fold risk of diisocyanate-induced asthma [95% confidence interval (CI) 1.01-3.52]. Moreover, among the asthma patients, the GSTM1 null genotype was associated with lack of diisocyanate-specific immunoglobulin (Ig)E antibodies [odds ratio (OR) 0.18, 95% CI 0.05-0.61] and with late reaction in the specific bronchial provocation test (OR 2.82, 95% CI 1.15-6.88). Similarly, GSTM3 AA genotype was related to late reaction in the specific bronchial provocation test (OR 3.75, 95% CI 1.26-11.2). The GSTP1 Val/Val genotype, on the other hand, was related to high total IgE levels (OR 5.46, 95% CI 1.15-26.0). The most remarkable effect was seen for the combination of GSTM1 null and the GSTM3 AA genotype which was strongly associated with lack of diisocyanate-specific IgE antibodies (OR 0.09, 95% CI 0.01-0.73) and with late reaction in the bronchial provocation test (OR 11.0, 95% CI 2.19-55.3). The results suggest, for the first time, that the polymorphic GSTs, especially the mu class GSTs, play an important role in inception of ill effects related to occupational exposure to diisocyanates.

Allergic contact dermatitis caused by acrylate compounds is common in dental personnel; they also often complain of work-related respiratory or conjunctival symptoms.The aim of the present study was to report the cases of acrylates induced respiratory hypersensitivity in dental personnel diagnosed in Finland during the last 6 years.Occupational asthma, rhinitis, laryngitis and pharyngitis cases were diagnosed according to patient history, PEF monitoring, and a work-simulating provocation test.Twelve cases of respiratory hypersensitivity caused by acrylates diagnosed in dental personnel (six dentists and six dental nurses) in 1992-97 are reported. During this period one case of conjunctivitis and one of laryngitis have been published separately. Nine cases of occupational asthma, two rhinitis cases, and one laryngitis case were verified according to the challenge tests with dental acrylate compounds (acrylates, methacrylates and epoxy acrylates). Only three patients had positive skin-prick test reactions to common environmental allergens, and none reacted to acrylates in the skin-prick tests. Five patients had an elevated total IgE (110 kU/L). PEF follow-up showed an occupational effect in all examined eight patients with diagnosed asthma. The mean duration of exposure to acrylates was 22 years, and the duration of respiratory symptoms 8 years.The results indicate that acrylates constitute an important hazard for dental workers. The mechanism of respiratory hypersensitivity is still unknown, and it is probably not IgE-mediated.

Polyester powder paints are extensively used in metal painting. Triglycidyl isocyanurate (TGIC), an epoxy compound, is often used as a hardener. Several cases of allergic eczema from occupational exposure to TGIC have been reported in the literature.We examined a 36-year-old non-smoking man who worked mainly as a spray painter, using a polyester powder paint containing 4% TGIC. During painting he used protective clothing and a motorized breathing protector. After 4 years he developed eczema on his hands, face and body, and an occupational allergic eczema caused by TGIC was diagnosed. He also suffered from powder-paint-related asthmatic symptoms.Occupational asthma was diagnosed in accordance with the accepted guidelines. Inhalation challenge tests were performed with the paint and TGIC.Spirometry showed slight obstruction; the blood eosinophils and serum IgE value were elevated. Skin-prick tests with common environmental allergens were negative. The challenge test with lactose powder was also negative. A challenge test with a paint containing TGIC (4%) induced a dual reaction in PEF and a late 23% fall in FEV1. A test with TGIC (4%) mixed with lactose induced a dual PEF reaction, and also dual changes in spirometry. The PD15 in the histamine challenge test decreased significantly after the challenge tests.To our knowledge this is the first diagnosed case of occupational asthma caused by TGIC. This case report emphasizes the importance of protecting both the skin and respiratory tract of workers against chemicals such as TGIC, capable of causing skin and respiratory allergy.

Only one case report concerning allergic alveolitis caused by polyester powder paint has been published previously. The aim of this study was to determine whether phthalic anhydride (PA) or trimellitic anhydride (TMA) is the alveolitis-causing agent in such paint. A 61 year old woman showed recurrent symptoms of chills, cough, and fever whilst at work. She was working in a plant where epoxy polyester powder paints were used to paint metal. The paint was found to contain low (1%) amounts of TMA and PA. The patient showed shadowing on chest radiographs. In bronchoalveolar lavage, lymphocytosis (67%) and a low T-helper/T-suppressor ratio (0.2) were found. Transfer factor was within normal limits, but a slight reduction was verified after re-exposure to the paint. The symptoms, exposure, reduction in transfer factor, findings on chest radiographs and bronchoalveolar lavage were consistent with allergic alveolitis. In conclusion, the polyester powder paint used in the plant caused allergic alve olitis in this patient. Of the constituents in the paint, trimellitic anhydride and phthalic anhydride were the possible causative agents.

A drill core sample penetrating at a natural fracture has been analysed by helium gas techniques and by α-autoradiography. Porosity and diffusivity profiles away from the fracture have been determined and compared with structural profiles. Model calculations are used to determine the effects of sample size on the measured porosities and diffusivities.

Incidence figures show that occupational asthma is increasing. It often takes a deteriorating course. Follow-up studies of workers suffering from the disease have uniformly reported persistence of symptoms over long periods, even among formerly exposed workers. New initiators of occupational asthma are continuously being reported. Still "old" agents, such as diisocyanates and flours, remain major causes. There seems to be some disconnection in the dialogue between the medical and the technical parties involved. For prevention, it is essential to ensure that important information not only reaches those who are responsible for designing and maintaining processes, but that it is presented in an intelligible form. Occupational asthma has become an important occupational disease that merits high priority. Recent achievements should facilitate preventive actions. However, prevention is a multidisciplinary enterprise needing the commitment of industrial hygienists and engineers, chemists, and allergologists, in addition to that of occupational health personnel.

Transport due to toroidal ηi and collisionless trapped electron modes is studied using an advanced reactive fluid model. Transport code simulations of DIII‐D and JET discharges are analyzed. The recent experimental results with off‐axis electron cyclotron heating in the DIII‐D tokamak [Phys. Rev. Lett. 68, 52 (1992)] are recovered with inward flow of electron energy and peaked electron temperature profile. For the JET equilibria the model gives heat diffusivities of the correct order of magnitude which grow with radius up to r/a=0.8.

Several points concerning the section ‘‘Comparison with the Swedish stability and transport analysis’’ in the paper by Horton et al. are discussed and clarified. In particular it is pointed out that the Swedish model gives about the right ratio of χe/χi for the Tokamak Fusion Test Reactor (TFTR) [Phys. Rev. Lett. 63, 520 (1989)] density modification experiment.