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The idea of the global balance of spine stems from Jean Dubousset, who first introduced the concept of cone of economy. Through the compensatory mechanisms, the human body maintains an upright posture and horizontal gaze in the setting of the spinal malalignment. Compensation takes place not only in the mobile spine segments, but also in the pelvis and lower extremities. Patients with a malalignment exhibit compensatory changes in the cervical hyper-lordosis, posterior pelvic shift, knee/ankle flexion, hip extension, and the pelvic retroversion. The advent of whole-body stereo radiography has yielded an improved understanding of global changes among the patients. Deformity-induced compensatory changes in the sagittal alignment could be resolved reciprocally after the surgical correction of the malalignment. Thoracolumbar realignment surgery restores the pathologic compensatory changes in the unfused spinal segments, pelvis, and the lower extremities. Similarly, reciprocal changes in the thoracolumbar spine may harmonize global sagittal alignment after the cervical reconstruction. This study reviews the compensatory mechanisms and reciprocal changes in global sagittal alignment caused by the surgical correction and highlights, the factors that should be considered while assessing a patient’s compensatory status.

The plasma healing of acute wound on 56 hairless mice is examined and initiated by several externally controlled physical parameters such as driving frequency and power, duration and interval of plasma treatment, a fraction of air mixture, the gap distance between plasma and wound, and others. The variation of these physical parameters results in a different amount of reactive oxygen and nitrogen species (RONS), which stimulate the regulation of RONS in mouse tissue before revealing several important bioindicators in the process of wound healing. While focusing on an important physical indicator such as the wound size, the limited examination with 56 mice showed promising results [much improved over the previous mice experiments by single-frequency plasma (SP)] by Dual-frequency plasma (DP) with 2% air mixture to argon, which effectively correlates with the observation of optical emission spectra. Circular acute wounds treated by DP (2%) were reduced to 24% in just 8 h after the treatment and further reduced to 5% within a few days.

BACKGROUND A lifestyle characterized by poor eating habits and physical inactivity is a risk factor for multiple lifestyle diseases in young adults. This study assessed the effects of implementing an intensive 10-day health promotion program combining diet and physical activities on body composition, physical fitness, and biochemical parameters of young adults. MATERIAL AND METHODS In this randomized pilot study, 30 female undergraduate students were randomly allocated to an intervention and a control group. The health promotion program consisted of unlimited amounts of vegetarian food; aerobic, flexibility, and strength exercises (3 hours/day); lectures on health (3 hours/day); massage practice (2 hours/day); and healthy cooking practice (1 hour/day). The effects of the intervention were analyzed using the Mann-Whitney U test and the Wilcoxon signed-rank test. RESULTS The intensive 10-day health promotion program significantly reduced body weight, body mass index, triglyceride, total cholesterol, low-density lipoprotein cholesterol, blood glucose, and the homeostasis model assessment of insulin resistance. At the same time, participants demonstrated increased back muscle, leg muscle, and grip strength; waist and shoulder flexibility; balance; and cardiorespiratory endurance. CONCLUSIONS The intensive 10-day health promotion program is a viable intervention for improving body composition, physical fitness, glycemic control, and blood lipid levels in young adults.

Kinetic theory of electron acoustic waves (EAWs) in the presence of wave angular momentum has been derived to study the effect of wave angular momentum on the propagation of EAWs in a non-Maxwellian plasma. Both types of electrons (hot and cool) are modeled as Kappa distributed velocity distribution functions. The theory is also applied to Saturn's magnetosphere where these kinds of distribution functions are commonly found. It is seen that the presence of wave angular momentum in the model has a significant effect on the existence of the regions where EAWs are weakly damped. The effect of wave angular momentum on EAWs is studied by defining a parameter η = k/(lqθ), which is the ratio of the planar wave number to the azimuthal wave number. The wave is purely planar if η→∞. The weakly damped region of EAWs depends strongly on this parameter in addition to other parameters such as hot electron spectral index κh, cool electron spectral index κc, the fraction of hot electrons, and hot to cool electrons temperature ratio. The results also show the effect of η on the propagation of EAWs in various region of the Saturn's magnetosphere.

Using Ar/Air mixture microwave plasma, we investigated the effects of air and gas temperature on the generation of electrons, ozone (O3), and nitric oxide (NO) through experiments and chemical kinetics simulation. The global model (GM) chemical kinetics simulation was used to validate and complement experimental observations. As the air percentages in Ar plasma increase, electrons are mainly generated by reactive oxygen species (ROS), but electron densities decrease. This is why plasma jet length becomes shorter with the mixture of air to Ar plasma at the same power. The profile of O3 densities has a maximum point because these are affected by oxygen (O2) molecules and gas temperature. O3 densities increase because these are generated via recombination of atomic oxygen (O) and O2 radicals as the air percentages increase. As the gas temperature increases, O3 densities decrease and O3 radicals are mainly destroyed by ROS such as O2−, excited O2, and O, although air percentages increase. NO radicals increase continually with the addition of air mixture and increase in gas temperature. With respect to biomedical applications, in the case of Ar/Air plasma treatment, it takes just 2 d, which has reduced the wound area to 30% because of faster scab formation over the wound and mRNA activation. Abundant NO radicals with ROS in Ar/aAir plasma strongly enhance IL-6 and TGF-β1, which facilitate collagen remodeling and wound recovery effectively.

To show the long-term fate of the herbicide mefenacet in rice paddies, [aniline-14C]mefenacet was applied to a lysimeter of loamy soil with a depth of 1 m, and rice plants were cultivated for 6 consecutive years according to the conventional methods in Korea. Mineralization of [14C]mefenacet to 14CO2 and volatilization from the soil surface were 12.01 and 0.02 %, respectively, of the originally applied amount during the first 23 weeks following application. Throughout the 6-year period, the total proportion of 14C-radioactivity that leached through the lysimeter soil was 0.778 % of the original radioactivity. The total 14C-radioactivity absorbed and translocated by rice plants throughout the 6 years was 2.46 % of the applied 14C. Measurement of the 14C-radioactivity distributed in each part of the rice plant (the straw, the ears without rice grain, the chaff, and the brown rice grain) indicated that the amount of 14C in straw was 25.87 times higher than that in brown rice grain over the 6 years. The 14C-radioactivity remaining in the soil layer after 6 years was 44.58 % of that applied, 91.45 % of which was distributed in the upper 0–20-cm layer. These results strongly indicate that mefenacet moved downward very slowly and more than half of the herbicide applied was released into the air, mainly through mineralization to CO2 in soil during the experimental period.

Using surface type air atmospheric pressure plasma, we investigated the amount of ozone and other reactive species generation with variations of the surface temperature of an electrode through an optical emission spectrum and a tube type gas detector. Reduced version of global model (GM) was employed to complement these experimental observations. The results of the model matched well with the experimental data. The amount of ozone generated from the surface type air plasma device was dramatically reduced with increasing temperature. Atomic oxygen (O) and nitric oxide (NO) radicals, which are important agents for biomedical applications, proportionally increased with increasing temperature. We also elucidated the dominant reaction related to the generation or loss of these radicals based on temperature variation through our GM.

Oral cavity and teeth are important organs of human body. The attention and cost for dental treatments increase every year. In dental clinics, the most common diseases are dental caries, periodontal disease, and stomatitis. Dental aesthetics such as tooth whitening is one of important part of dental clinics. However, conventional treatment methods in dental clinics have limitations by pain and long-time treatment. Nonthermal plasmas have shown great potential as noble techniques to dental applications due to safety and multi-functional effects achieved by the abundant plasma components including charged particles, radiation, and reactive species. Reactive oxygen species generated from plasmas can effectively inhibit pathogen activity. The use of nonthermal plasmas is efficient in treating oral diseases because the construction of the plasma devices allows easy access to the oral cavity. However, few studies have been conducted on the use of plasmas in oral disease. Tooth aesthetics, as well as treatment of oral diseases, are important in determining the quality of human life. Recent studies have shown nonthermal plasmas to have strong tooth-bleaching effects. Studies on oral care using nonthermal plasmas will significantly contribute to oral health in the future.

Energy-based surgical devices are widely used to fuse tissues and seal vessels, but tissue adhesion to the instrument complicates the procedure. We deposit a robust non-stick coating on the jaws of LigaSure tissue fusion devices by employing an atmospheric pressure RFdriven plasma with hexamethyldisiloxane (HMDSO) entrained in argon carrier gas. The hydrophobicity, surface energy, surface topography, and chemical characteristics of deposited films are characterized by water contact angle measurements, surface energy test pens, atomic force microscopy, and Fourier transform infrared spectroscopy, respectively. We demonstrate significantly reduced tissue adhesion to HMDSO polymer film-coated instruments during the tissue fusion procedure in comparison with uncoated and chromium nitride-coated instruments.

Radio frequency (RF) driven hybrid gaswater plasma for tooth whitening was developed and the plasma chemical reactions with de-ionized (DI) water were studied. Plasma operating conditions, such as RF input power and argon flow rate were correlated with plasma lengths. The operation of hybrid gaswater plasma changed both the electrical conductivity and pH concentration of the DI water. OH and H2O2 densities were measured to determine the dominant species generated by plasma. The major chemical reaction pathways and known rate constants are given in support of the analysis of major chemical reaction pathways. Finally, we demonstrated that the hybrid gaswater configuration achieved porcine tooth whitening.

Unique atmospheric pressure plasma devices are designed to investigate the plasma characteristics for various driving frequencies under the same operating conditions. Electrical properties of the plasma, gas temperature, formation of plasma jets, and sterilization efficiency are studied for two different driving frequencies of 13 kHz (low frequency) and 877 MHz (microwave frequency). When compared with low frequency plasma, microwave plasma is found to have better electrical properties such as no electric shock for safety, high discharge current for effective chemical reactions, clean waveform for homogenous plasma, and high power coupling efficiency. Furthermore, microwave plasma leads to effective sterilization which is related to the high intensity of atomic oxygen. One-dimensional particle-in-cell simulation reveals that microwave plasma has substantial electrons in the energy range 2–5 eV (bond dissociation energy), thus electrons in this energy range can produce more atomic oxygen. It shows that the probability of producing high energy ions, which can damage the electrode, is low in microwave plasma.

Helium (He) and Argon (Ar) atmospheric pressure plasma jets operated with low-frequency power source are designed and studied. The current and voltage waveforms, formation of plasma jets, estimated rotational and vibrational temperatures, optical emission spectra, and numerical simulations for He and Ar gases are investigated to analyze the plasma characteristics. Ar plasma shows higher discharge current and many instantaneous current peaks compared with He plasma. For gas flow between 1 and 7 L/min and applied voltage between 3 and 10 kV, no significant changes in Ar plasma are observed. He plasma is found to be sensitive as far as gas flow rate and applied voltage are concerned. This sensitivity is associated with a transition from laminar to turbulent mode of gas flow. The estimated gas temperatures show higher values for Ar plasma than those of He plasma. Ar plasma jet emits extremely high intensity of OH (305 nm ~312 nm) and O (777 nm) compared with that emitted from He plasma jet. High concentration of OH and O in Ar plasma is related with high density of electrons with 4-5 eV, which is in the range of the dissociation energy of H-H, O-H, and O=O bonds. As a result, wider sterilization area and higher sterilization efficacy in indirect treatment are observed for Ar plasma than He plasma.

A low-power palm-size microwave power module for portable microwave-excited plasma applicable to biomedicine is integrated on a single printed circuit board for the first time. The designed board includes a power amplifier chip, a phase-locked loop (PLL) chip, and an impedance matching network with microstrip lines. In addition, as a part of the true one-chip integration of the plasma power module, the PLL is designed and fabricated in a semiconductor chip with a 0.18-μm CMOS technology for dedicated use to our plasma source. For the plasma generator, a 900-MHz coaxial transmission line resonator is used with argon gas flow. The designed plasma source is applied to the inactivation of S. mutans, showing three-log reduction within 180-s treatment. Measurements for the different initial concentrations (from 105 to 10 9 CFU/mL) are also conducted, and the outcomes are discussed. The results verify the feasibility of the proposed integrated microplasma source for use in dental treatments.

Three-electrode plasma jet system consisting of a perforated dielectric tube with two outer and one floating inner electrodes was developed and employed for tooth bleaching. Lowered gas breakdown voltage and increased discharge current were achieved by using the floating inner electrode. Optical emission spectra analysis showed that the rotational temperature of the second positive nitrogen bands was ≈290 K and vibrational temperature was ≈2 500 K, which means this plasma is in highly non-quilibrium state and nonthermal. The presence of excited He, N2, N and O in the plasma plume was revealed. The plasma jet was used in combination with hydrogen peroxide (H2O2) to remove stains from extracted teeth stained by either coffee or red wine. Combining the plasma jet and H2O2 improved the bleaching efficacy by a factor of 3.1 (coffee) and 3.7 (red wine) compared with using H2O2 alone.

We demonstrated that room temperature plasma could be used for tooth bleaching. A nonthermal, atmospheric pressure, helium plasma jet device was developed to enhance the tooth bleaching effect of hydrogen peroxide (H(2)O(2)). All teeth were sectioned sagittally into halves, which were assigned randomly to either the experimental group or the control group. The experimental group was treated with H(2)O(2) (28%, 20 microL every 30 seconds) plus plasma (5 W) for 10 minutes; the control group was treated with H(2)O(2) alone for the same duration. Removal of the tooth surface protein was demonstrated by scanning electron microscopy images and Ponceau staining. Production of hydroxyl radicals (.OH) was measured by using electron spin resonance spin-trapping. Combining plasma and H(2)O(2) improved the bleaching efficacy by a factor of 3 compared with using H(2)O(2) alone. Tooth surface proteins were noticeably removed by plasma treatment. When a piece of tooth was added to a solution of H(2)O(2) as a catalyst, production of *OH after plasma treatment was 1.9 times greater than when using H(2)O(2) alone. We suggest that the improvement in tooth bleaching induced by plasma is due to the removal of tooth surface proteins and to increased *OH production.

The results of simulations using a fluid model and a PIC-MCC model are compared, and the PIC-MCC is used to explore the kinetics of energetic ions and electrons in microplasmas. The kinetics are studied under helium discharges at 760 Torr and Ne/Xe DBD discharges at 300 Torr with various driving currents and geometries. While EEPFs of microplasmas at high pressure show strong nonequilibrium behavior near the sheath region, EEDFs on the powered and grounded electrodes have qualitatively different features depending on input power. The effective temperature and energy flux of charged particles can be obtained from the slopes in EEPFs and IEPFs. The effects of input power, discharge length, and mixture gas concentration on the IEDFs on each electrode are discussed.

Atmospheric pressure glow discharges (APGDs) have widespread applications, including sterilization, cancer cell treatment, deposition, and surface modification due to their rather simple configurations, thanks to no need for vacuum system and their great capability to generate reactive species such as radical oxygen species. Helium and argon are widely used as feeding gases, achieving stable operations for wide ranges of parameters in atmospheric pressure, and oxygen is added into these gases to generate more reactive oxygen species (ROS), which play a significant role in sterilization. As the measurements of species densities and electron temperature in APGDs are difficult, we have developed the zero-dimensional global model of He/O 2 and Ar/O 2 APGDs to calculate the densities of several kinds of species and electron temperature. It was shown that even though small fraction of oxygen less than 1% was added to helium or argon, electrons dissipated most of their energy through collisions with oxygen molecules rather than helium or argon atoms. The densities of electron, atomic oxygen, and ozone of Ar/O 2 were higher than those of He/ O 2 ; however, the electron temperature of He/O 2 was higher than that of Ar/O 2 . When the pulsed power is applied, the time-averaged electron temperature for the shorter pulse period and the larger duty ratio increased, and the electron density decreased as the duty ratio increased.

Thanks to their portability and the non-equilibrium character of the discharges, microplasmas are finding application in many scientific disciplines. Although microplasma research has traditionally been application driven, microplasmas represent a new realm in plasma physics that still is not fully understood. This paper reviews existing microplasma sources and discusses charged particle kinetics in various microdischarges. The non-equilibrium character highlighted in this manuscript raises concerns about the accuracy of fluid models and should trigger further kinetic studies of high-pressure microdischarges. Finally, an outlook is presented on the biomedical application of microplasmas.

The results of a particle-in-cell Monte Carlo collision (PIC-MCC) simulation of a direct current (DC) helium microplasma that operates at atmospheric pressure are presented. Electron and ion kinetic information that is not available from previous fluid studies is reported. Despite the high collisionality at atmospheric pressure, electrons are found to be in nonequilibrium. Similar to large-scale low-pressure dc discharges, the electron energy probability function (EEPF) in the bulk plasma presents three temperatures near the cathode, and it evolves into a bi-Maxwellian distribution as electrons approach the anode. The bi-Maxwellian character of the EEPF in the elastic energy region is not accounted for in fluid models, and as a result, PIC-MCC simulations predict a lower electron temperature than fluid models. The mean energy of ions that are impinging on the cathode is found to be significantly lower than in low-pressure discharges due to the large collisionality of the sheaths.

A stereoselective approach for synthesizing (2R,5S)-dihydroxymethyl-(3R,4R)-dihydroxypyrrolidine 1 (2,5-dideoxy-2,5-imino- d -glucitol, DGDP) was achieved using a seven-step approach starting from 2,3,4,6-tetra-O-benzyl- d -mannose (7). Key steps for the preparation of the title compound 1 involved the regioselective and diastereoselective amination of the cinnamyl anti-1,2-polybenzyl ethers 5 and 6 using chlorosulfonyl isocyanate (CSI) and ring cyclization to form the pyrrolidine ring. The reaction between anti-1,2-polybenzyl ether 5 and CSI in toluene at 0 °C afforded the corresponding anti-1,2-amino alcohol 4 as a major product with a diastereoselectivity of 16:1 in 76% yield. The mechanism underlying these reactions may be explained by the neighboring-group effect leading to the retention of stereochemistry.

The sputtering of the MgO protective layer by energetic ions is one of the factors limiting the lifetime of the plasma display panels (PDPs). The sputtering profile of the MgO layer in a coplanar PDP cell has been studied using two-dimensional particle-in-cell Monte-Carlo Collision (PIC–MCC) simulations. The sputtering profile of the MgO layer for various gas conditions is obtained accounting for the energy and angle distributions of different ion species and their respective sputtering yields. Based on the simulation results, the MgO layer is more aggressively sputtered in Ne-based discharges than in He-based discharges. As a result, it is expected that the addition of He to the Ne-Xe mixture in PDPs will reduce the sputtering of the MgO layer and extend the lifetime of the PDP cells.

Electron and ion kinetics in a micro hollow cathode discharge are investigated by means of two-dimensional axisymmetric particle-in-cell Monte Carlo collision simulations. Argon discharges at 10 and 300 Torr are studied for various driving currents. Electron and ion energy probability functions (IEPF) are shown at various times and locations to study the spatio-temporal behaviour of the discharge. The electron energy probability function (EEPF) evolves from the Druyvesteyn type in the early stages of the discharge into a two (or three) temperature distribution when steady state is reached. In steady state, secondary electrons accelerated across the cathode fall populate the high energy tail of the EEPF while the low energy region is populated by trapped electrons. The IEPF evolves from a Maxwellian in the negative glow (bulk) to a two temperature distribution on the cathode surface. The overpopulation of low energy ions near the cathode surface is attributed to a larger collision cross section for low energy ions and ionization within the cathode fall.

Particle-in-cell and hybrid electron-Boltzmann simulations of planar and cylindrical Langmuir probes are compared with various probe theories. Floating potentials for planar and cylindrical probes are calculated and significant deviations from the typical approximation used for argon discharges of ∼5Te are shown. The interpretation of simulated ion saturation currents by the orbital motion limited and the Laframboise theories result in an overestimation of the ion density. On the other hand, the cold-ion theory underestimates the ion density. These deviations are related to the overestimation and underestimation, respectively, of the ion orbital motion around cylindrical probes. The best agreement is obtained when the probe theory suggested by Tichy et al. is used. This theory incorporates ion orbital motion as in the Laframboise theory, collisional orbital motion destruction as suggested by Zakrzewski and Kopiczynski, and ion scattering as given by Chouet al.

A statistical procedure for modelling the cumulative effect of multiple collisions in particle simulations is presented. The procedure approximates the probability density function (PDF) of the final scattering angle and that of the particle net displacement by parametric functions. Formulae for determining the moments of the exact PDFs as a function of the statistics of a single collision event are derived. Using these formulae, the parametric functions can be fitted to yield the same first moments as the real distributions. Therefore, in contrast to other approaches where after one iteration the error in the first moments depends on the number of collisions modelled, the present model provides always the right moments. Correlation between the scattering angle and the displacement of the particle is also considered and enforced by means of a Gaussian copula.

The process of a dust-grain charging in developing air plasma with an external source S (cm/sup -3/ s/sup -1/) is studied analytically and numerically in drift-diffusion approximation. It is shown that, when the source is turned on, the steady-state level of electron concentration in the bulk plasma is attained rather quickly (the time being determined by the attachment rate). The time of establishing the ion concentration depends on the source intensity as S/sup -1/2/. In the steady state, the ratio of ion-to-electron concentrations is proportional to the source intensity as S/sup -1/2/ and can be very large for low-intensity sources. As a consequence, the process of a dust-grain charging in developing plasma differs significantly for low- and high-intensity sources. At sufficiently high rates of ionization, the grain charge in air is comparable to that in electropositive gases. For low-intensity sources when the ion concentration exceeds that of electron by several orders of magnitude, the grain charge is of the order of several tens of electron charges. The oscillating regime of a dust-grain charging is observed for low-intensity sources.

A homogeneous plasma model for dual radio-frequency (rf) discharges driven by two sinusoidal current sources has been analyzed. Under the assumptions of time-independent and collisionless ion motion and inertialess electrons, the analytic expressions for discharge parameters are obtained as a function of the effective parameters such as effective frequency, effective current, and effective voltage. Effective parameters are determined by the ratio of two currents or voltages. Two rf sources are generally coupled to each other through the plasma medium. It is also shown that the reduction of the bulk plasma length due to the sheath size has to be considered for calculating the discharge parameters since the sheath length is not always negligible compared to the bulk plasma length. Furthermore, the dependence of discharge parameters on the low frequency is presented.

In order to improve production efficiency, large-diameter wafer substrates (300-mm diameter) and large-area glass substrates (from 400 cm/sup 2/ to 1 m/sup 2/) have been adopted recently. As a result, the development of large and high-density plasma source has become essential. To investigate the discharge phenomenon in the chamber that consists of embedded antenna coil in the rectangular system (1020 /spl times/830 /spl times/437 mm), we have developed a two-dimensional fluid simulation model. In order to check our model, the results from our simulation have been compared with available experimental data. The comparison is generally in a good agreement with experiments. Depending on the current direction and powered method, the distribution of plasma parameters has many differences. In our simulation with a chamber larger than is usually used in other experiments, we examine three effects: the distance between antenna coils, structure in the chamber, and the depth of the chamber. The parameters, which affect nonuniformity, electron temperature, and others, can be explained in a manner similar to the inductively coupled plasma source with a cylindrical chamber. Our simulation results confirm that the embedded antenna coil system with a suitable environment can be extended by many antenna coils as a large-area plasma source.

To improve the low luminous efficiency of a coplanar-type ac plasma display panel cell, two kinds of new cell designs have been proposed using two-dimensional numerical simulation. To generate more excited xenon atoms in the anode and the cathode regions, we use additional one or two small electrodes in conventional geometry. An auxiliary electrode between two sustain electrodes induces the positive column discharge by the particular driving voltage pulse waveform. Moreover, two bus electrodes embedded in the dielectric layer play an important role in creating excited xenon species. The use of these additional electrodes results in 80%-90% increment of the luminous efficiency in comparison with the conventional model.

In order to elucidate the long-term fate of the sulfonylurea herbicide cinosulfuron, the 14C-labelled chemical was applied to a clay loam soil, encased in two lysimeters, 22 days after rice (Oryza sativa L.) transplanting, and rice plants were grown for four consecutive years. Throughout the experimental period, leaching through soil profiles, absorption and translocation by rice plants, and distribution of 14C by downward movement in the soil layers were clarified. The total volume of leachates collected through the lysimeter soil over the four years amounted to 168 and 146 L in lysimeters I and II, respectively. The leachates contained 2.43% and 2.99% of the originally applied 14C-radioactivity, corresponding to an average concentration of 0.29 and 0.41 microg/L as the cinosulfuron equivalent in lysimeters I and II, respectively. The total 14C-radioactivity translocated to rice plants in the third and fourth year was 0.69% and 0.60% (lysimeter I), and 1.02% and 0.84% (lysimeter II) of the 14C applied, respectively. Larger amounts of cinosulfuron equivalents (0.54-0.75%) remained in the straw in the fourth year than in any other parts. The 14C-radioactivities distributed down to a depth of 70 cm after four years were 56.71-57.52% of the 14C applied, indicating the continuous downward movement and degradation of cinosulfuron in soil. The non-extractable residues were more than 88% of the soil radioactivity and some 45-48% of them was incorporated into the humin fraction. The 14C-radioactivity partitioned into the aqueous phase was nearly 30% of the extractable 14C, suggesting strongly that cinosulfuron was degraded into some polar products during the experimental period. It was found out in a supplemental investigation that flooding and constant higher temperature enhanced mineralization of [14C]cinosulfuron to 14CO2 in soil, indicating the possibility of chemical hydrolysis and microbial degradation of the compound in the flooded lysimeter soil.

Partially ionized, low-temperature plasmas have been used extensively in many areas of technology. These applications of plasma include surface processing and lighting devices. There are three major categories in surface processing: sputtering, etching and surface modification. The examples of lighting device application are light bulbs, lasers and plasma display devices. In this discussion, simulation study of magnetron sputtering system are reviewed and future issues of these systems are discussed. A two-dimensional three-velocity particle-in-cell (PIC) code is used to simulate kinetic plasma properties in a planar magnetron system with realistic magnetic fields in two and three dimensions. Various plasma characteristics and erosion profiles of a target material are obtained with these magnetic fields. Scaling formulas are used in order to estimate the steady-state properties of plasma and reduce computation time. Variations in the geometry and the magnetic field optimize these erosion profiles and plasma characteristics. For the plasma characteristics, we also calculate the plasma temperature and the velocity distribution function. The velocity distribution function of electrons is nearly Maxwellian, while that of ions is non-Maxwellian. The electron temperature in the bulk coincides well with the experimentally measured values. The majority of ions are in the energy range below half of the applied voltage.

A detailed analysis, based on kinetic and fluid simulations, of striation phenomenon in the plasma display panel cell has been presented. Numerical studies indicate that the phenomenon of striation occurs primarily due to the accumulation of space charge near the anode electrode. These space charges locally create multiple-layer potential distribution near the anode region. The ion density in the vicinity of this region groups up due to ionization processes, which are caused by electron species. However, the electrons are further attracted by the anode. Well-like deformations occur in the anode potential distribution, which confine electrons and produce density humps. On the contrary, cathode plasma density depends on the secondary-electron emission by ions that are attracted to the anode dielectric surface.

This paper presents modeling and experimental results of the voltage, current, and density profiles of a helical resonator plasma source. The source has a 5/4-wavelength (/spl lambda/) helical resonator structure with the helical coil short-circuited at one end and open circuited at the other end. When the radio frequency (RF) tap for power feeding was located at an odd multiple of /spl lambda//4 from the short-circuited end, the observed voltage, current, and plasma density were higher in the short-circuited section than those in the open-circuited section. The opposite property was observed with the RF tap at an even multiple of /spl lambda//4. A microstrip transmission line model was used to explain the experimental results. The model accurately predicted the RF voltage and current profiles. After calculation of RF voltage and current, the plasma density was solved numerically. The difference between the calculated and measured plasma density was within a factor of two. The changes on the density profile indicate that the transport properties of plasma can be adjusted with the RF tap position.

The ion-beam dynamics is simulated for a bounded dusty plasma with the immobile dust particles. Since there is no dust motion, the growth of an instability is induced dominantly from the Pierce instability, but the beam motion is also greatly influenced by the Debye-shielding thermal electrons whose densities are determined from the Boltzmann relation. The analytic calculation of a dispersion relation shows the nonexistence of a uniform equilibrium which is confirmed by simulations. A period-doubling route to chaos is observed and the various nonlinear oscillations are classified in view of a diagnostic parameter which is applied to many other beam systems.

Tokamak plasmas with highly elongated cross sections are subject to a vertical displacement event (VDE). The nonlinear magnetohydrodynamic (MHD) evolutions of tokamak plasmas during the VDE are simulated by a three-dimensional MHD code as a combination of N = 0 and N = 1 components. The nonlinear evolution during the VDE is strongly affected by the relative amplitude of the N = 1 to the N = 0 modes.

Nonlinear dynamics and self-oscillations in a dc beam-driven collisional discharge are investigated with particle-in-cell simulation and theoretical estimation. Three different modes, anode-glow, temperature-limited, and double-layer modes, are observed in the system. A theory for the critical voltage of mode transition between temperature-limited and anode-glow modes is in good agreement with the simulation results. The mechanism of low frequency self-oscillation in the double layer mode is examined along with period-doubling and chaotic oscillations.