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Some Eurasian shrubs, including species of Lonicera, have become invasive in North America. Recently, Lonicera caerulea cultivars have been developed from Eurasian germplasm and promoted for North American markets as honeyberry, haskap, or sweetberry honeysuckle. Checklist-based evaluation tools offer insight into the invasive potential of non-native plants introduced to North America, but can be difficult to utilize effectively for taxa with limited cultivation histories. The recent arrival of L. caerulea to North America's horticulture trade makes it difficult to answer questions that rely on an established history of ecological interactions in an introduced range. The only ecological observation that we have found in North America is a 2011 report of a naturalized woodland population of reproductive honeyberry shrubs in Minnesota. However, in northern Europe, the Norwegian Biodiversity Information Centre reported that Eurasian L. caerulea has spread rapidly from planted localities, and poses risks of severe impacts to Norway's natural plant communities. Our best interpretation of available data used in two risk-assessment tools developed for North America indicates that cultivars of Eurasian L. caerulea pose a high risk of invasiveness. A complicating factor is the native occurrence of the closely related mountain fly honeysuckle [Lonicera caerulea subsp. villosa (Michx.) A. Love & D. Love] and blue fly honeysuckle [Lonicera caerulea subsp. cauriana (Fernald) B. Boivin] in portions of North America where cultivars of Eurasian L. caerulea have been promoted. Fly honeysuckles tend to be sporadic, small in stature, and not particularly productive; conversely, Eurasian cultivars have been hybridized and selected for rapid growth and high yield. Unanswered concerns include: 1) should L. caerulea germplasm from Eurasia be considered native in North America; 2) could hybrid, Eurasian genotypes of L. caerulea exhibit greater competitive fitness than the North American fly honeysuckles; and 3) will the introduction of Eurasian L. caerulea cultivars have population genetic consequences for indigenous fly honeysuckles?

This chapter reviews multichannel broadband measurement of the soft-X-ray radiation and total radiation in magnetically confined fusion plasma experiments. Common detector types used (including bolometers), details of their application, and interpretation of their measurements are described. An introduction is given to the application of computed tomography methods in the mathematical reconstruction of emission profiles from multiple (approximately) line-integral measurements, taking into account the specific circumstances common in magnetically confined fusion plasma experiments. Although the emphasis is on two-dimensional tomography of poloidal cross sections, the applications of Abel inversion, three-dimensional tomography, vector tomography, and other specific methods are briefly discussed. Several examples of the application and the plasma parameters that can be derived are given.

Steady state divertor operation with high performance plasmas (ne ~ 0.7 × 1019 cm−3, Ti ~ 2 keV) was demonstrated for half an hour in the Large Helical Device (LHD), the superconducting helical device (R = 3.6–3.9 m, a = 0.6 m, B = 3 T, l/m = 2/10). The high performance plasmas have been sustained with an averaged heating power of 680 kW and achieved an injected energy of 1.3 GJ. This required both advanced technological integration of heating systems and divertor heat flux control. In particular, optimization of divertor heat flux distribution along the divertor leg trace on divertor plates and real-time magnetic axis sweeping (R = 3.67–3.7 m) have allowed LHD to access a steady state regime with a margin of safety for the actively cooled divertor plates. The distribution of divertor heat load along the traces was investigated with calorimetric measurements and it was found that there was a localized heat load connected with the loss of high-energy ions produced by ion cyclotron radio frequency near-fields. Orbit analysis shows that the behaviour of high-energy ions is qualitatively in good agreement with the experimental result. Long-pulse discharges were terminated by radiation collapse due to penetration of metallic flakes into the plasma.

In the Large Helical Device (LHD), two different divertor configurations, i.e. helical divertor (HD) and local island divertor (LID), are utilized to control the edge plasma. The HD with two X-points is an intrinsic divertor for heliotron devices, accompanied with a relatively thick ergodic layer outside the confinement region. Edge and divertor plasma behavior from low density to high density regimes is presented, referring to the divertor detachment. The effect of the ergodic layer on the edge transport is also discussed. On the other hand, the LID is an advanced divertor concept which realizes a high pumping efficiency by the combination of an externally induced magnetic island and a closed pumping system. Experimental results to confirm the fundamental divertor performance of the LID are presented.

A long-pulse plasma discharge for more than 30 min. was achieved on the Large Helical Device (LHD). A plasma of ne = 0.8× 1019 m−3 and Ti0 = 2.0 keV was sustained with PICH = 0.52 MW, PECH = 0.1 MW and averaged PNBI = 0.067 MW. Total injected heating energy was 1.3 GJ, which was a quarter of the prepared RF heating energy. One of the keys to the success of the experiment was a dispersion of the local plasma heat load to divertors, accomplished by shifting the magnetic axis inward and outward.

Results of the two-dimensionally reconstructed distribution of soft X-ray emission in HL-2A and electromagnetic radiation in large helical device (LHD) are presented. Hardware improvements of in-vessel soft X-ray cameras and the development of tomographic software have made detailed and visual studies of soft X-ray emission possible in HL-2A. Several algorithms are employed in order to get as detail as possible in the images while keeping the guiding assumptions to a minimum. Recently success has been achieved in applying a 2D peeling away algorithm for tomographic reconstruction of LHD bolometric data jointly under the China-Japan collaboration. The data analysed so far have been used to study magnetohydrodynamic (MHD) instabilities on HL-2A tokamak and radiation losses on LHD.

The positive density dependence of energy confinement times, ?E, as expressed in the international stellarator scaling 95 (ISS95), where ( is the line-averaged density and P is the heating power), declines in high-collisionality regimes in the large helical device experiments. In the low-collisionality regime, where parameter dependences in ISS95 agree well with the experiment, the temperature dependence of thermal diffusivity is as strong as predicted by the gyro-Bohm model and/or the neoclassical theory. As the collisionality increases to the plateau regime, the temperature dependence becomes moderate, where the thermal diffusivity is proportional to the square root of the electron temperature. Furthermore, the thermal diffusivity is inversely proportional to the magnetic field strength and the electron temperature gradient is proportional to the electron temperature in the high-collisionality regime. Compared with ISS95, the energy confinement time expected from these observations has a weaker density dependence together with mitigated power degradation: .

Characteristics of MHD instabilities and their impacts on plasma confinement are studied in current free plasmas of the Large Helical Device. Spontaneous L?H transition is often observed in high beta plasmas close to 2% at low toroidal fields (Bt ? 0.75?T). The stored energy starts to rise rapidly just after the transition accompanying the clear rise in the electron density but quickly saturates due to the growth of the m = 2/n = 3 mode (m and n: poloidal and toroidal mode numbers), the rational surface of which is located in the edge barrier region, and edge localized mode (ELM) like activities having fairly small amplitude but high repetition frequency. Even in low beta plasmas without L?H transitions, ELM-like activities are sometimes induced in high performance plasmas with a steep edge pressure gradient and transiently reduce the stored energy up to 10%. Energetic ion driven MHD modes such as Alfv?n eigenmodes (AEs) are studied in a very wide range of characteristic parameters (the averaged beta of energetic ions, ?b?, and the ratio of energetic ion velocity to the Alfv?n velocity, Vb?/VA), of which range includes all tokamak data. In addition to the observation of toroidicity induced AEs (TAEs), coherent magnetic fluctuations of helicity induced AEs (HAEs) have been detected for the first time in NBI heated plasmas. The transition of a core-localized TAE to a global AE (GAE) is also observed in a discharge with temporal evolution of the rotational transform profile, having a similarity to the phenomenon observed in a reversed shear tokamak. At low magnetic fields, bursting TAEs transiently induce a significant loss of energetic ions, up to 40% of injected beams, but on the other hand play an important role in triggering the formation of transport barriers in the core and edge regions.

Standard diagnostics for fundamental plasma parameters and for plasma physics are routinely utilized for daily operation and physics studies in the large helical device (LHD) with high reliability. Diagnostics for steady-state plasma are under intensive development, especially for Te, ne (yttrium–aluminium garnet (YAG) laser Thomson, CO2 laser polarimeter), data acquisition in steady-state and heat-resistant probes. To clarify the plasma properties of the helical structure, two- or three-dimensional diagnostics are being aggressively developed: tangential cameras (fast SX TV, photon counting CCD, Hα TV); tomography (tangential SX CCD, bolometer); imaging (bolometer, ECE, reflectometer). Divertor and edge physics are important key issues for steady-state operation. Diagnostics for neutral flux (Hα array, Zeeman spectroscopy) and ne (fast scanning probe, Li beam probe, pulsed radar reflectometer) are also in advanced stages of development. In addition to these, advanced diagnostics are being intensively developed in LHD through domestic and international collaborations.

Internal transport barriers with respect to electron thermal transport (eITB) were observed in the large helical device, when the electron cyclotron resonance heating (ECH) power was highly localized on the centre of a plasma sustained by neutral beam injection. The eITB is characterized by a high central electron temperature of 6–8 keV with an extremely steep gradient, as high as 55 keV m−1 and a low electron thermal diffusivity within a normalized average radius ρ≈0.3 as well as by the existence of clear thresholds for the ECH power and plasma collisionality.

Bolometer diagnostics are installed on the Large Helical Device (LHD) to provide measurements of the total (broad spectrum) electromagnetic radiation emitted by the plasma. Three types of detectors are used: resistive metal film bolometers, absolute extreme ultraviolet photodiodes and infrared imaging video bolometers. Details of the installation in LHD are given for each type of detector. The detector calibration, data analysis and tomography techniques are described and compared and sample results are shown.

The behaviour of high-energy ions accelerated by an ion cyclotron range of frequency (ICRF) electric field in the large helical device (LHD) is discussed. A better confinement performance of high-energy ions in the inward-shifted magnetic axis configuration was experimentally verified by measuring their energy spectrum and comparing it with the effective temperature determined by an electron slowing down process. In the standard magnetic axis configuration a saturation of the measured tail temperature was observed as the effective temperature was increased. The ratio between these two quantities is a measure of the quality of transfer efficiency from high-energy ions to a bulk plasma; when this efficiency was compared with Monte Carlo simulations the results agreed fairly well. The ratio of the stored energy of the high-energy ions to that of the bulk plasma was measured using an ICRF heating power modulation method; it was deduced from phase differences between total and bulk plasma stored energies and the modulated ICRF heating power. The measured high energy fraction agreed with that calculated using the injected ICRF heating power, the transfer efficiency determined in the experiment and the confinement scaling of the LHD plasma.

Intrinsic impurity behaviour in neutral beam heated LHD long pulse discharges with a discharge duration of 10 s was investigated. Spectroscopic and bolometric measurements showed a remarkable temporal increase of core radiation due to metallic impurities. Central impurity accumulation was found in a narrow plasma density region (e = 1–3×1019 m−3) for both density ramp-up discharges and constant density discharges. In the density ramp-up discharges, high-Z impurities were accumulated in the low-density region and diffused out from the core plasma in the high-density region. The impurity behaviour was compared with neoclassical predictions.

The energy confinement time of net current-free plasmas in the Large Helical Device (LHD) is comparable to ELMy H-mode with q = 4.5 on the scale of IPB98(y,2). Broad temperature with high edge pressure, which is of robust nature in LHD, recalls the pedestal structure in tokamak H-mode. Basic parameter dependence is, however, weak gyro-Bohm in both edge and core regions. This suggests that one physical model could explain the observed profile. The edge temperature is proportional to the square root of heating power and inversely proportional to the square root of edge density. This means that edge pressure and its gradient are not limited and can be increased by heating power.

The flattening of the electron density profiles due to the static magnetic island is observed when the n/m = 1/1 perturbation field is applied by the external coil. The iso-density widths are estimated from the model fitting analysis. The temporal history of the iso-density width and its dependence on normalized collision frequency and plasma β are estimated from a single shot. The iso-density width increases as the external perturbation field increases. Although determination errors are not small compared with the dynamic range of the estimated iso-density width, the following tendencies are observed. The iso-density width shows positive dependence on logarithm of normalized collision frequency and negative dependence on β.

Positive radial electric field, Er, was observed at the edge region in the low-density NBI plasmas of the Large Helical Device (LHD). Ion thermal diffusivities, χi, are evaluated by the local transport analysis for two different density plasmas and for two cases of the magnetic axis position. In the standard configuration case, χi was reduced by large positive Er, while no reduction in χi was found in the inward shifted case. A certain level of suppression of the neoclassical ripple transport by Er seems to be confirmed since the neoclassical transport is considered to be more dominant in the standard magnetic configuration plasmas.

The improvement in the particle confinement of pellet shots on the Large Helical Device (LHD) was found after methane (CH4) mixed hydrogen gas-puff discharges. Only four discharges introducing ∼20 Pa m 3 of CH4 caused the reduction in the radiation loss and the level of metal impurities, together with the enhanced recycling, which is expected as the real time carbonization effect. The decay rate of the electron density was mitigated in the pellet shot after CH4 discharges. Transport analysis shows 60% reduction in the particle transport coefficient at half the averaged minor radius.

Neutral beam injection heated discharges at the density limit in the Large Helical Device [O. Motojima, H. Yamada, A. Komori et al., Phys. Plasmas 6, 1843 (1999)] are terminated with asymmetric radiative collapse (ARC) exhibiting several properties in common with the MARFE (multifaceted asymmetric radiation from the edge) phenomenon: (1) A highly poloidally asymmetric radiation profile which is stronger on the inboard side. (2) This asymmetry is well correlated with the signal from the multichord interferometer. (3) Moreover, evidence from several diagnostics at different toroidal locations supports the possibility that ARC may be toroidally symmetric. However in contrast to MARFE, ARC is only observed in the period just prior to the quench of the plasma.

The present work is intended to renew the interest in a basic understanding of the stationary transport of Heliotron E with direct ion heating in the framework of neoclassical theory. It should be noticed here that the experimental evaluation of {Chi}{sup exp}{sub i} in such a low collisional regime in heliotron/torsatron configuration was for the first time achieved in this study. However, the transport can be enhanced by turbulence, resulting in the degraded conditions like the L-mode of tokamak operation. In this connection this paper also discusses the possible contribution from the drift wave turbulence that is expected to affect the anomaly of the observed heat fluxes. The ion heat transport in the outer region of the plasma was interpreted as being enhanced by the electrostatic drift wave modes on the basis of the proposed diffusivity model. The result obtained through these analyses has stimulated our further efforts for producing a more collisionless regime where the electric field will control the transport. 11 refs., 6 figs.

Recent results of Heliotron E experiment are reviewed. Detailed studies of the plasma transport have been achieved in Heliotron E, in which the plasma wall interaction has been changed using the ECH boronization technique. The boronization realized low-density, high-T{sub i} plasmas whose ion collisionality deeply estended to the 1/{nu}{sub i}** regime. The local electron and ion thermal diffusivities in the NBI plasma are analyzed and discussed by comparison with theory-based transport models. The particle transport in ECH plasmas is investigated with edge fluctuation measurements. Both electrostatic and magnetic fluctuations are well correlated with the global particle confinement. Characteristic structures of the electric field or potential distribution are observed during the particle confinement degradation phase. It is considered that dc convective flow across the last closed flux surface is caused by the potential structure. Edge plasma flows have been discussed in connection with these studies and with asymmetric divertor heat/particle load. 10 refs., 9 figs.

Mach probe measurements of bias-induced ion flows were made in the Interchangeable Module Stellarator (IMS) as a function of neutral pressure and viscosity (which increases with minor radius) and compared to a fluid theory model. Using a probe model for an unmagnetized plasma, the poloidal flow speed measured with a Mach probe agrees with that calculated from momentum balance to within 15%. The dependencies of the measured ion flow magnitudes and decay rates on neutral pressure and viscosity as predicted by the theory are qualitatively observed in the experimental measurements, clearly demonstrating the effects of both ion-neutral collisions and viscosity in the damping of the bias-induced flows. However, the measured flow direction is nearly poloidal, while the theory predicts a predominantly Pfirsch-Schlueter-like toroidal flow. Also the two-dimensional variation at a constant toroidal angle of the parallel electron current was measured in an unbiased plasma. The measured profiles demonstrate the dependence of the current on both the radial pressure gradient and the cosine of the poloidal angle, as predicted by theory. 11 refs., 5 figs.

A Mach probe is used to measure poloidal and toroidal flows induced by a biased electrode in IMS. Mach probe theories are reviewed and classified as either magnetized or unmagnetized. A simple geometric model of the IMS Mach probe shows that the variation of the effective probe area as a function of the probe orientation with respect to the magnetic field is 20%–25%, predicting the probe to be only slightly magnetized. Measurements of the variation in the total ion saturation current collected by the probe, as the angle with respect to the magnetic field is varied, demonstrate this level of magnetization only at low neutral pressure at large minor radius, while in other cases the variation in the total collected current is negligible. Based on this result an unmagnetized model [M. Hudis and L. M. Lidsky, J. Appl. Phys. 41, 5011 (1970)] is chosen to analyze the IMS Mach probe data. Comparison of Mach probe poloidal flow measurements as a function of minor radius to calculations of the E×B drift velocity an...

This study used several model-based tools to analyse the dynamics of the Arctic Basin between 1997 and 2006 as a linked system of land-ocean-atmosphere C exchange. The analysis estimates that terrestrial areas of the Arctic Basin lost 62.9 Tg C yr-1 and that the Arctic Ocean gained 94.1 Tg C yr-1. Arctic lands and oceans were a net CO2 sink of 108.9 Tg C yr-1, which is within the range of uncertainty in estimates from atmospheric inversions. Although both lands and oceans of the Arctic were estimated to be CO2 sinks, the land sink diminished in strength because of increased fire disturbance compared to previous decades, while the ocean sink increased in strength because of increased biological pump activity associated with reduced sea ice cover. Terrestrial areas of the Arctic were a net source of 41.5 Tg CH4 yr-1 that increased by 0.6 Tg CH4 yr-1 during the decade of analysis, a magnitude that is comparable with an atmospheric inversion of CH4. Because the radiative forcing of the estimated CH4 emissions is much greater than the CO2 sink, the analysis suggests that the Arctic Basin is a substantial net source of green house gas forcing to the climate system.DOI: 10.1111/j.1600-0889.2010.00497.x

Recent analyses of land-use change in the tropical regions and in the temperate and boreal regions of the earth were combined to yield a global estimate of 1.0 - 2.6 x 1015 g C for the net release of carbon to the atmosphere in 1980 from changes in land use. Deforestation in the tropics accounted for nearly all of the flux; the net release of carbon from temperate and boreal regions was only 0.1 x 1015 g C. The average global value of 1.8 x 1015 g C in 1980 was distributed geographically among tropical countries and other regions on the basis of deforestation rates and carbon stocks. The net release of carbon from changes in land use worldwide is inconsistent with the results of geochemical models of the carbon cycle. The discrepancy is smaller than in previous analyses, but is large enough to exceed the errors of the analysis. Possible explanations for the discrepancy include the possibility of a net accumulation of carbon in undisturbed ecosystems as a result of CO2 fertilization or changes in climate. Even if the terms of the global carbon equation were to appear balanced at present, current knowledge is insufficient to predict whether terrestrial ecosystems will act as a positive or negative feedback on the anticipated CO2-caused global warming.DOI: 10.1111/j.1600-0889.1987.tb00277.x

The time-of-flight neutral particle measurement system1 has been installed on the 10-O port at the 2nd campaign. It has the capability of two-dimensional measurement with a larger viewing angle by using the pivot on the rectangular port, which is set inside of the 10-O mother port. The movable stage with the vertical scan mechanism rotates on the fan shaped stainless rails around the pivot. The sight lines of −2 to 32 degrees against the 10-O port surface makes the angle between the sight line and the magnetic axis of the standard configuration (3.6 m) of 95 to 35 in the 4th campaign. Therefore the analyzer can observe high-energy particles with these pitch angles. The higher scan speed of 0.17 degree/second than that in the last campaign (0.05 degree/s) can be obtained in this campaign. Precise spatial distribution of the high-energy particles can be expected because it enables the continuous scanning in the long discharge.

Diagnostics for helical systems are reviewed. A helical system is expected to be a disruption-free steady-state reactor since no plasma current is required. Different types of medium-sized helical systems such as CHS1, W7-AS2, Heliotron E3 and J4, H-1NF Heliac5 and HSX have been developed and constructed. Recently, a large helical device (LHD) has been constructed in Japan and another large one (W7-X8) is under construction in Germany. These two devices are fully equipped with superconducting magnets, modern diagnostics and high power heating systems. The plasma parameters are expected to be comparable to large tokamaks. While most plasma diagnostics are similar to those for tokamaks, there are also specific features: (1) measurement of vacuum magnetic flux surfaces; (2) intrinsic 3-D structure including divertor; (3) intensive diagnostics for the electric field; (4) diagnostics to verify device design elements; (5) high density diagnostics; (6) steady state operation. W7-X optimization principles call for sensitive current diagnostics (Pfirsch-Schluter and bootstrap currents) and tomographic means to verify the reduced Shafranov shift as well as fast particle confinement diagnostics11. Steady state or long pulse operation fulfills the demands of correlation diagnostics as Te fluctuation measurements, it allows for coherent averaging and it enables scans of various diagnostics. Examples are: i) polarization scans of ECE, ii) wavelength scans of spectrometers, and iii) spatial scans of several diagnostics. The special features of diagnostics for helical systems are described in the following chapters.

We studied the association of Parkinson's disease (PD) with type of menopause (natural or surgical), age at menopause, and postmenopausal estrogen replacement therapy using a case-control design. We used the medical records-linkage system of the Rochester Epidemiology Project to identify 72 women who developed PD in Olmsted County, MN, during the twenty years 1976-1995. Each incident case was matched by age (+/- 1 year) to a general population control subject. We collected exposure data through review of the complete medical records of cases and control subjects in the system. PD cases had undergone hysterectomy (with or without unilateral oophorectomy) significantly more often than control subjects (odds ratio [OR] = 3.36; 95% confidence interval [CI] = 1.05-10.77). In addition, PD cases had experienced early menopause (or = 46 years) more commonly than control subjects (OR = 2.18; 95% CI = 0.88-5.39). Finally, PD cases had used estrogens orally or parenterally for at least 6 months after menopause less frequently (8%) than control subjects (14%; OR = 0.47; 95% CI = 0.12-1.85). However, the findings for early menopause and estrogen replacement therapy were not statistically significant. Despite the limited sample size of this exploratory study, we hypothesize that there is an increased risk of PD in conditions causing an early reduction in endogenous estrogen. This hypothesis needs to be confirmed in a larger study.

We studied the association between preceding psychiatric disorders and Parkinson's disease (PD) using a case-control design. We used the medical records-linkage system of the Rochester Epidemiology Project to identify 196 subjects who developed PD in Olmsted County, Minnesota, during the years 1976-1995. Each case was matched by age (+/-1 yr) and sex to a general population control. We reviewed the complete medical records of cases and control subjects to detect preceding psychiatric disorders. The frequency of psychiatric disorders was higher in cases than in control subjects; the odds ratio was 2.2 for anxiety disorders (95% confidence interval [95% CI] = 1.4-3.4; p = 0.0003), 1.9 for depressive disorders (95% CI = 1.1-3.2; p = 0.02), and 2.4 for both anxiety disorders and depressive disorders occurring in the same individual (95% CI = 1.2-4.8; p = 0.02). When we restricted analyses to disorders present 5 years or more before the onset of motor symptoms of PD, the association with depressive disorders lost statistical significance. However, the association with anxiety disorders remained significant for disorders present 5, 10, or 20 years before onset of motor symptoms. Our results suggest that anxiety disorders and depressive disorders are associated with PD and that the causative process or the risk factors underlying PD are present many years before the appearance of motor symptoms.

The confinement characteristics of large net-current-free plasmas heated by neutral-beam injection have been investigated in the Large Helical Device (LHD). A systematic enhancement in energy-confinement times from the scaling derived from the medium-sized heliotron/torsatron experiments have been observed, which is attributed to the edge pedestal. The core confinement is scaled with the Bohm term divided by the square root of the gyro radii. The comparative analysis using a dimensionally similar discharge in the Compact Helical System indicates gyro-Bohm dependence in the core and transport improvement in the edge region of LHD plasmas.

In LHD discharges a significant enhancement of the global energy confinement has been achieved for the first time in a helical device with an edge thermal barrier, which exhibits a sharp gradient at the edge of the temperature profile. Key features associated with the barrier are quite different from those seen in tokamaks: (i) almost no change in particle (including impurity) transport, (ii) a gradual formation of the barrier, (iii) a very high ratio of the edge temperature to the average temperature, and (iv) no edge relaxation phenomenon. These features are very attractive in applying the thermal barrier to future reactor grade devices.

It is found that resonant magnetic perturbation (RMP) fields have a stabilizing effect on the radiating edge plasma, realizing stable sustainment of radiative divertor (RD) operation in the Large Helical Device (LHD). Without RMP, thermal instability leads to radiative collapse. Divertor power load is reduced by a factor of 3–10 during the RMP-assisted RD phase, while maintaining relatively good core plasma confinement with confinement enhancement factor . It has also been demonstrated that the RMP field itself can initiate transition to RD operation by increasing perturbation strength, while keeping constant density and injection power. The results show a possibility of a new control knob for divertor power load in a 3D magnetic field configuration. It is also found that after the transition to RD, the energy confinement enhancement factor based on ISS04 scaling increases by a factor of 1.4 compared with the attached phase. The operation range of the RMP-assisted RD is identified in terms of RMP strength and radial location of the resonance layer of the RMP. A 3D edge radiation structure is analysed using the edge transport code EMC3-EIRENE and the results are compared with experiments. The comparison indicates that the application of RMP modulates the 3D edge radiation structure such that an intense radiation appears around the X-point of the m/n = 1/1 island in the case with RMP, while it is located at the inboard side without RMP.

The natural stable isotope values of different plants have been used to trace the fate of organic carbon that enters estuarine ecosystems. Experiments were designed to determine the magnitude of (delta) (sup13)C changes of dissolved organic carbon (DOC) derived from tidal marsh vegetation that occurred during bacterial decomposition. Bacteria were grown on DOC leached from estuarine Spartina alterniflora and Typhus angustifolia plants. In four experiments, 25 to 80% of the initial carbon (2.6 to 9.1 mM organic C) was converted to bacterial biomass and CO(inf2). Mass balance calculations showed good recovery of total C and (sup13)C at the end of these experiments (100% (plusmn) 14% total C; (plusmn) 1(permil) (delta) (sup13)C). The (delta) (sup13)C values of DOC, bacterial biomass, and respired CO(inf2) changed only slightly in the four experiments by average values of -0.6, +1.4, and +0.5(permil), respectively. These changes are small relative to the range of (delta) (sup13)C values represented by different organic carbon sources to estuaries. Thus, microbial (delta) (sup13)C values determined in the field helped to identify the source of the carbon assimilated by bacteria.

The effects of acute hypoxemia on cardiovascular responses to dopamine (DA) and dobutamine (DB) were studied in 2-4 day (n = 21) and 13-17 day (n = 27) old swine under sodium pentobarbital anesthesia. Sequential 10-min infusions of 2, 5 and 15 mu/kg/min of DA or DB or normal saline were administered under conditions of normoxemia and repeated during hypoxemia. Data are presented as mean percent of baseline value +/- SE. During normoxemia, DA increased aortic pressure, cardiac output, heart rate, LV dP/dt max and renal resistance and decreased mesenteric resistance in both ages, while DB increased heart rate, LV dP/dt max and cardiac output in both age groups and decreased total arterial resistance and renal resistance in the youngest. Increases in LV dP/dt max were larger with DA as compared to DB (p less than 0.05) with the highest dose in younger (152 +/- 5% vs. 124 +/- 4%) and older (201 +/- 29% vs. 157 +/- 9%) animals. Hypoxemia reduced heart rate responses to DA and DB in older piglets, contractility responses to DB in older animals, aortic pressure responses to DA in all animals and renal resistance responses to DA in older animals. Hypoxemia had little or no effect on cardiac output and total arterial, mesenteric and carotid resistance responses to DA and DB. Thus, in the newborn: 1) DA is a stronger inotropic agent during normoxemia and hypoxemia while the chronotropic effects of the two drugs did not differ. 2) Changes in cardiac output with both drugs did not differ significantly during normoxemia and were not affected by hypoxemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypoxia is a complication which frequently occurs in human infants who have experienced perinatal stress. Although cardiovascular (CV) responses to hypoxia are well documented in both the fetus and adult, there is limited information about the postnatal maturation of regional circulatory responses to hypoxia, still less on the sympathetic rhythm generating systems (SRGS), as monitored by recordings of spontaneous efferent sympathetic (SAMP) activity. On the other hand, the effects of hypoxia on the developing respiratory rhythm generator (RRG) have been well documented in many species (cf. Gootman et al., 1989; Steele, 1986). In our previous studies, maturation- related responses to other stresses, i.e., hemorrhage and hypercapnia, were observed in swine (Buckley et al., 1984; Gootman et al., 1985; Reddy et al., 1974). This animal model is less mature at birth than lambs and guinea pigs, and more mature at birth than puppies, rats, and kittens (N.M. Buckley, 1983, 1986; Gootman, 1983). This paper summarizes our studies on the effects of two degrees of hypoxia on four different regional circulations and on efferent SYMP and phrenic activity in swine from birth to 2 months of age.

Two 20-channel absolute x-ray ultraviolet photodiode (AXUVD) cameras are being used on the large helical device for measuring the two-dimensional radiation distribution. The local radiation emissivity is obtained by inverting the measured brightnesses with linear (Tikhonov-Phillips) or nonlinear (maximum entropy) regularization methods. The most important features of these improved methods are the capability of reconstructing radiation distributions without any symmetry assumptions, built-in smoothing, and useful reconstructions with relatively few detector channels. Together with improvements in the analysis method, the current AXUVD system makes it possible to obtain radiation emissivity images of various localized radiative phenomena, such as radiation collapse or transport of impurities injected into the plasma.

Recent progress in the heating capability in the large helical device [O. Motojima et al., Phys. Plasmas 6, 1843 (1999)] has allowed the highest average beta value (4.1%) obtained in the helical devices, and enables exploration of magnetohydrodynamics (MHD) stability in this beta region. MHD activities in the periphery are found to become stable spontaneously from the inner region to the outer region when the averaged beta value exceeds a threshold, and then a flattening of the electron temperature profile is observed around the resonant surface. Such a flattening can be formed externally by producing an m/n=1/1 magnetic island, and the complete stabilization of the m/n=1/1 mode is demonstrated by the moderate island width. In addition, attempts to control peripheral plasmas are also performed by using a limiter and a local island divertor utilizing the m/n=1/1 island, to improve plasma confinement and, especially, to stabilize pressure-driven modes in the present study. The stabilization of peripheral MHD modes is obtained with both approaches, and this indicates that these are available to the production of higher-beta plasmas without edge MHD activities.

Morbidity and death during liver resection in children are due to hemorrhage and the consequences of massive transfusion. To overcome these problems, a new rapid method of blood transfusion was used in four children (8 to 35 months, 8.6 to 13 kg) undergoing extensive hepatic resection for tumor (tumor weight, 440 to 1625 gm). The rapid infusion device consisted of a roller pump and a bubble oxygenator-warmer circuit primed with washed packed red cells resuspended in fresh-frozen plasma and calcium-free balanced salt solution (Plasmalyte). The infusate was warmed, oxygenated, and buffered before it was administered. An average of 5130 ml per patient of this reconstituted blood was infused at an average rate of 122 +/- 45 ml/min, with peak infusion rates sometimes as great as 1 L/min. Cardiac output, pulmonary artery wedge pressure, body temperature, urine output, blood gases, blood chemistries, and coagulation factors remained unchanged during and after these massive transfusions. Blood transfusion at rapid rates required during pediatric liver resection can be accomplished safely if the storage lesion of the bank blood is previously corrected.

Diets containing expeller-extracted linseed meal treated with corn oil, lard or coconut oil were fed to lambs to determine the effectiveness of coating the protein in reducing its ruminal degradation. Three common indicators of nitrogen metabolism in the ruminant were used in evaluation: ruminal ammonia, blood plasma ammonia and plasma urea. Eight crossbred lambs, averaging 27 kg in weight, were allotted to the four diets which were fed at a rate of 350 g at 12-hour intervals. Ruminal ammonia, plasma ammonia and plasma urea were monitored at 0, 2, 4, 6 and 8 hr after feeding. Lambs consuming coconut oil-treated linseed meal produced less rumen ammonia (average of .5 mg/100 ml across all collection times) than those fed normal linseed meal (10.3 mg/100 ml). Lambs fed corn oil-treated and lard-treated linseed meal had ruminal ammonia levels intermediate to those fed normal and coconut oil-treated linseed meal. Levels of plasma ammonia and plasma urea nitrogen of normal linseed meal were significantly higher than the same measures with the oil-treated linseed meals. Differences in plasma ammonia and urea nitrogen were not significant among the three oil-treated diets.

New stellarator experiments have been launched since the last compilation of the international stellarator database in 1995. Parameter regimes have been extended by Large Helical Device (LHD), and a variety of improved modes have been found since then. The revision of the international stellarator database has been initiated, driven by these emerging interests and by the requirements for a reactor assessment. Some provisional issues are discussed. An understanding of configurational effects is a prerequisite to the derivation of a unified scaling. Differences in magnetic geometry are influential in characterizing energy confinement. The results from the magnetic axis and elongation scans in LHD are highlighted. Comparison with tokamak confinement is also addressed. The revision of the database is in progress, and this paper is an interim report.

Wall boronization was applied in Heliotron E with special reference to the study of impurity and recycling control in the helical system. However this technique was also found to work as an advantageous tool to enhance the diagnostic sensitivity of the beam impedance method for measuring the edge and divertor field line structure. In this paper we describe a new approach to the beam impedance method that utilizes the wall boronization.