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HEALTH EFFECTS OF POTASSIUM CHLORATE-EXPOSED LONGAN DRYING FACTORY WORKERS
No full textAbstract This study was to investigate health effects of longan drying factory workers who were exposed to potassium chlorate or its metabolites. A descriptive design was applied to this study using interviewing questionnaires and recording forms. The samples comprised 199 workers working in various factories located in Muang district, Lumphun province. Seventy-nine percent of the workers were female, with a mean±SD age of 43.0±11.3 years. Sixty-four percent performed three steps of the longan drying process, i.e., peeling off, rinsing, and aligning longans in a tray in the mean daily working hours of 10.6±5.2. Sixty-eight percent did not wear gloves during their work. Sixty-six percent provided a history of allergy after working in the factories. Physical examination results showed lesions of occupation-related skin diseases on their hands and other parts of the body (21.0%). Laboratory investigations indicated that some workers were in the stage of anemia, leukocytosis, thrombocytopenia, and methemoglobin emai with percentages of 31.2%, 6.5%, 0.5%, and 35.2%, respectively. These values were statistically different from those of the normal population (p-value<0.05). The urinalysis also revealed hematuria and pyuria in 22.0% and 20.5% respectively, whereas, 7.5% had both hematuria and pyuria. The findings of this study suggested that longan drying factory workers might be at risk of potassium chlorate toxicities. Further analytical studies should be employed to prove this remark. Chiang Mai Med Bull 2001; 34(4):173-176
2772 Magnetospheric Physics: Plasma waves and instabilities; 6984 Radio Science: Waves in plasma
Full text link[1] Waves with frequencies in the vicinity of the proton cyclotron frequency and its harmonics are commonly observed from the Fast Auroral Snapshot spacecraft when traversing regions of auroral particle acceleration. In areas of upward current, largeamplitude electromagnetic waves with frequencies within 5% of the local proton gyrofrequency p and its harmonics are often observed where upstreaming ion beams exist. These waves have electric field (E 1 ) and magnetic field (B 1 ) amplitudes of up to 1 V m À1 and 2 nT with the ratio E 1 /B 1 as small as c. The waves occur in the low-altitude portion of the primary auroral acceleration potential, where plasma densities are 1 cm À3 . It is shown how these waves grow through inverse Landau resonance with a cold field-aligned electron beam superimposed on an accelerated and magnetically mirrored plasma sheet electron component in the absence of any significant plasma densities at energies below $100 eV. Significantly, the drift velocity of the cold beam (v oeb ) is several times larger than its thermal velocity v eb , and it is this feature that allows the wave to become electromagnetic at cyclotron harmonics while simultaneously giving rise to broadband electrostatic emissions spanning the first few cyclotron harmonics as is observed
Uncertainty in Modeling the Dynamics of Structures in Mid-frequency Range
No full textAbstract: Based on measurements of energy content in single struts of a complex truss structure, a numerical simtiat ion of truss dynamics was performed using the Direct Dynamic Stiffness Method, Simulation and restits of measurements were in good agreement, cotiming that there are distinct energy-levels for different wave types in the structure. Variations of parameters reveaf a high sensitivity towards sma~differences in the model, which requires averaging over fairly broad frequency intervals to obtain reliable predictions for real structures. REAL STRUCTURE AND NUMERICAL MODEL A numerical model of the truss structure shown in It was used to validate previous measurements [I] and to generalize the findings with respect to other complex structures. The truss consists of 109 aluminium struts connected at 35 joints. The high number of struts and the strong The simulations confirm that energy levels of different wave types are clearly separated. The energy level of the flexural waves is approx. 10 dB and 30 dB above the energy levels of longitudinal and torsional waves, The similar frequency dependence of the different energy levels suggests a strong coupling between all wave types. The main stopband measured at 3000 Hz is shifted to 2700 Hz in the simulations and is more dominant,
Bifurcation theory for the L-H transition in magnetically confined fusion plasmas Bifurcation theory for the L-H transition in magnetically confined fusion plasmas
No full textThe mathematical field of bifurcation theory is extended to be applicable to 1-dimensionally resolved systems of nonlinear partial differential equations, aimed at the determination of a certain specific bifurcation. This extension is needed to be able to properly analyze the bifurcations of the radial transport in magnetically confined fusion plasmas. This is of special interest when describing the transition from the low-energy-confinement state to the high-energy-confinement state of the radial transport in fusion plasmas (i.e., the L-H transition), because the nonlinear dynamical behavior during the transition corresponds to the dynamical behavior of a system containing such a specific bifurcation. This bifurcation determines how the three types (sharp, smooth, and oscillating) of observed L-H transitions are organized as function of all the parameters contained in the model
Feedback-Controlled Traffic Shaping for Multimedia Transmissions in a Real-Time Client-Server System
No full textThe number of applications requiring real-time transmission of multimedia streams over the existing network structure is increasing
