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Growing dedicated bioenergy crops on marginal land can provide beneficial outcomes including biomass production and energy, resource management, and ecosystem services. We investigated the effects of harvest timing (peak standing crop [PEAK] or after killing frost [KF]) and nitrogen (N) fertilizer rates (0, 56, and 112 kg N ha−1) on yield, nutrient concentrations, and nutrient removal rates of perennial grasses on a wet marginal land. We evaluated three monocultures, including switchgrass (Panicum virgatum L., SW), Miscanthus x giganteus (MG), prairie cordgrass (Spartina pectinata Link, PCG), and a polyculture mixture of big bluestem (Andropogon gerardii Vitman), Indiangrass (Sorghastrum nutans (L.) Nash), and sideoats grama (Bouteloua curtipendula Torr., MIX). Increasing the application of N did correlate with increased biomass, concentration, and subsequent removal of nutrients across almost all treatment combinations. In all grass treatments except MG, PEAK harvesting increased yield and nutrient removal. At PEAK harvest, switchgrass is ideal for optimizing both biomass production and nutrient removal. While our results also suggest short-term plasticity for farmers when selecting harvest timing for optimal nutrient removal, KF harvest is recommended to ensure long-term stand longevity and adequate nutrient removal. If the KF harvest is adopted, MG would be the ideal option for optimizing biomass yield potential. Additionally, we found that the yield of polyculture did not vary much with harvest timing, suggesting better yield stability. Future studies should give consideration for long-term evaluation of polyculture mixtures to assess their biomass yields and nutrient removal capacities.

Objective: To compare fasting insulin-like growth factor binding protein 1 (IGFBP-1) to other fasting indices as a surrogate marker of insulin sensitivity and resistance calculated from a 3-hour oral glucose tolerance test (oGTT). Methods: Fasting IGFBP-1 and oGTT were performed at 0 (n = 77), 52 (n = 54), and 100 (n = 38) weeks in a study investigating metformin treatment of obesity in adolescents. Insulin area-under-the-curve (IAUC) and the composite insulin sensitivity index (CISI) calculated from the oGTT were compared to fasting IGFBP-1, homeostasis model assessment–insulin resistance, and corrected insulin release at the glucose peak (CIRgp). Results: IGFBP-1 and the ratio of IGFBP-1 to fasting insulin were significantly correlated with indices based on timed sampling, including IAUC, CISI, and CIRgp. In addition, a significant effect of IGFBP-1, but not IGFBP-1 to insulin at time zero, was observed for IAUC and CISI. Conclusion: Our results indicate that fasting IGFBP-1 may be a useful mar...

To evaluate the robustness of MR transverse relaxation times of trabecular bone from spin-echo and gradient-echo acquisitions at multiple spatial resolutions of 7 T.The effects of MRI resolutions to TIn the defatted trabecular experiment, both TT

This study aimed at optimising structural material topology in terms of node and element density by using the eigenvalue of thin steel and concrete plates. The topology optimisation condition presented in this study called to maximise the natural eigenfrequency with specific eigenmodes for a given set of boundary conditions. The numerical examples for generating steel or concrete members within the given design space verified optimal solutions depending on varied-order eigenmodes and Poisson's ratio, and resulted in new shapes and topology of thin plates for use in the building construction industry.

Background and purpose Although early cerebellar symptoms are one of the exclusive criteria in the diagnosis of progressive supranuclear palsy (PSP), cerebellar involvement in PSP is evident both clinically and pathologically. However, structural analysis focusing on the cerebellum has not been previously studied in patients with PSP. We aimed to evaluate cerebellar involvement in PSP using a magnetic resonance imaging-based segmental volumetric analysis. Methods We retrospectively enrolled 48 patients with PSP composed of 25 patients with PSP–Richardson's syndrome (RS) and 23 patients with pure akinesia with gait freezing, 39 patients with Parkinson's disease (PD) and 34 healthy controls. Data on both the whole and segmented cerebellar volumes were analyzed using a fully automated procedure. Results A general linear model showed that whole cerebellar volume in patients with PSP was significantly smaller compared with that of patients with PD or controls after controlling for age, sex and intracranial volume (P = 0.34). In addition, patients with PSP exhibited decreased regional volume in the crus I, lobule VIIIa and lobule VIIIb, which play roles as secondary representations of motor tasks, compared with patients with PD or controls. In subgroup analysis of PSP, volume loss in the whole and segmental cerebellum was more pronounced in patients with PSP-RS than in those with pure akinesia with gait freezing, PD or control subjects. Conclusion These data demonstrate that cerebellar atrophy is evident in patients with PSP and is especially prominent in the PSP-RS group. These findings increase understanding of the clinicopathological basis of cerebellar involvement in PSP.

Heat recirculation effects on flame propagation and flame structure are theoretically and experimentally examined in a mesoscale tube as the simplest model of heat-recirculating burners. Solutions for steady propagation are obtained using a one-dimensional two-temperature approximation. The results show that the low heat diffusivities of common solid materials permit significant heat recirculation through the wall only for a slowly-propagating condition, otherwise the flame behaves almost like a freely-propagating nonadiabatic flame. This limited heat recirculation sharply pinches and stretches two well-known branches of the freely-propagating nonadiabatic flame, resulting in the appearance of two slow-propagation branches. On the upper slow-propagation branch flames can reach superadiabatic temperatures and on the lower one, which is stretched from the classical unstable lower branch, flames can be stable. As the tube inner diameter decreases, another burning regime appears where flames are barely sustai...

The atmospheric mass density of the upper atmosphere from the spherical Starlette satellite’s Precise Orbit Determination is first derived with Satellite Laser Ranging measurements at 815 to 1115 km during strong solar and geomagnetic activities. Starlette’s orbit is determined using the improved orbit determination techniques combining optimum parameters with a precise empirical drag application to a gravity field. MSIS-86 and NRLMSISE-00 atmospheric density models are compared with the Starlette drag-derived atmospheric density of the upper atmosphere. It is found that the variation in the Starlette’s drag coefficient above 800 km corresponds well with the level of geomagnetic activity. This represents that the satellite orbit is mainly perturbed by the Joule heating from geomagnetic activity at the upper atmosphere. This result concludes that MSIS empirical models strongly underestimate the mass density of the upper atmosphere as compared to the Starlette drag-derived atmospheric density during the geomagnetic storms. We suggest that the atmospheric density models should be analyzed with higher altitude acceleration data for a better understanding of long-term solar and geomagnetic effects.

An important goal in diesel engine research is the development of a means to reduce the emissions of nitrogen oxides (NOx). The use of a cooled exhaust gas recirculation (EGR) system is one of the most effective techniques currently available for reducing nitrogen oxides. Since PM (Particulate Matter) fouling reduces the efficiency of an EGR cooler, a tradeoff exists between the amount of NOx and PM emissions, especially at high engine loads. In the present study, we performed engine dynamometer experiments and numerical analyses to investigate how the internal shape of an EGR cooler affects the heat exchanger efficiency. Heat exchanger efficiencies were examined for plain and spiral EGR coolers. The temperature and pressure distributions inside these EGR coolers were obtained in three dimensions using the numerical package program FLUENT.

Atomic layer deposition (ALD) appears to be uniquely suited for coating substrates with ultrahigh aspect ratios (or similar 10(3)), including nanoporous solids. Here, we study the ALD of Cu and Cu3N on the inner surfaces of low-density nanoporous silica aerogel monoliths. Results show that Cu depth profiles in nanoporous monoliths are limited not only by Knudsen diffusion of heavier precursor molecules into the pores, as currently believed, but also by other processes such as the interaction of precursor and reaction product molecules with pore walls. Similar behavior has also been observed for Fe, Ru, and Pt ALD on aerogels. On the basis of these results, we discuss design rules for ALD precursors specifically geared for coating nanoporous solids.

The Hanbit magnetic mirror has a central cell, one anchor cell and one plug cell plus associated vacuum chambers. The Hanbit device has been involved in a series of experiments on stabilization of ...

The ability to visualize whole-brain vasculature is important for quantitative in vivo investigation of vascular malfunctions in cerebral small vessel diseases, including cancer, stroke and neurodegeneration. Transverse relaxation-based ΔR2 and ΔR2 * MR angiography (MRA) provides improved vessel-tissue contrast in animal deep brain with the aid of intravascular contrast agents; however, it is susceptible to orientation dependence, air-tissue interface artifacts and vessel size overestimation. Dual-mode MRA acquisition with superparamagnetic iron oxide nanoparticles (SPION) provides a unique opportunity to systematically compare and synergistically combine both longitudinal (R1 ) and transverse (ΔR2 and ΔR2 *) relaxation-based MRA. Through Monte Carlo (MC) simulation and MRA experiments in normal and tumor-bearing animals with intravascular SPION, we show that ultrashort TE (UTE) MRA acquires well-defined vascularization on the brain surface, minimizing air-tissue artifacts, and combined ΔR2 and ΔR2 * MRA simultaneously improves the sensitivity to intracortical penetrating vessels and reduces vessel size overestimation. Consequently, UTE-ΔR2 -ΔR2 * combined MRA complements the shortcomings of individual angiograms and provides a strategy to synergistically merge longitudinal and transverse relaxation effects to generate more robust in vivo whole-brain micro-MRA. Copyright © 2016 John WileySons, Ltd.

Oxygen re-equilibration kinetics, along with the equilibrium conductivity, have been measured on undoped, single-crystal TiO 2− δ , by a four-probe d.c. conductivity relaxation technique, against oxygen partial pressure in the range of − 16 P O 2 /atm) ≤ 0 at different temperatures in the range of 1173 ≤ T /K ≤ 1373. The isothermal conductivity varies as σ ∝ P O 2 m with m ≈ − 1/4, − 1/5 and − 1/6 in turn with increasing P O 2 up to 1 atm, suggesting a sequential variation of the majority ionic disorder types from Ti i to Ti i to V O , respectively. Contrary to the conventional knowledge that due to the local (defect) equilibrium postulate there should be one and only one chemical diffusivity or single relaxation time for a binary oxide, the oxygen re-equilibration kinetics has turned out to be twofold with two different relaxation times depending on oxygen activities. This is interpreted as being due to the independent relaxation of each sublattice of TiO 2 in an oxygen activity gradient applied, indicating a failure of local equilibrium during oxygen re-equilibration. From the two different relaxation times the chemical diffusion coefficients of component Ti and O are separately evaluated and subsequently, their self-diffusion coefficients. The latter are found to be in a good agreement with the literature data.

Photocatalytic inactivation of algae, Anabaena, Microcystis , and Melosira , was carried out with TiO 2 -coated Pyrex hollow glass beads under the illumination of UV light (370nm wavelength). After being irradiated with UV light in the presence of the TiO 2 -coated Pyrex glass beads, Anabaena and Microcystis , known as typical cyanobacteria, lost their photosynthetic activity, and the string of Anabaena cells and the colonies of Microcystis cells were completely separated into individual spherical ones. In the case of Melosira , which is a typical diatom, however, somewhat lower photocatalytic inactivation efficiency was obtained, which was believed to be due to the presence of the inorganic siliceous wall surrounding the cells of Melosira . The TiO 2 -coated hollow glass beads could successfully be employed for the practical application in a eutrophicated river under sunlight. More than 50% of the chlorophyll-a concentration could be reduced by the action of TiO 2 photocatalysis.

In the period of 1988–2001, 226 ARGOS fixed drifters were deployed in the Japan/East Sea (JES). From these and the historical file of temperature at a depth of 100 m, 15 m depth circulation and its variances in relationship to the seasonal mean warm and cold water regions were constructed on 0.5° resolutions. The strongest seasonal currents were: the East Korean Warm Current (EKWC), the Tsushima Current (TC), the North Korean Cold Current (NKCC) and local eastwards intensifications along the sub-polar frontal patterns. The TC and NKCC were observed during summer and drifters passed through the Soya Strait only in summer. The sub-polar front occurred along 40°N in the northeastern JES; a separate front occurred in winter that was associated with the flow of warm water restricted to the southern JES. Small eddy energy was found in the cold water regime and large eddy energy in the warm water regime. Satellite altimeter and drifter tracks were used to mark the Wonsan Eddy found in the East Korean Bay, a yearly late summer occurrence. Mechanical energy flux from the mean circulation to mesoscale eddies occurred in EKWC, TC and the sub-polar front in the eastern JES with eddy kinetic energy doubling time of 15–60 days. The yearly mean circulation east of the Korean coast is organized into a broad, eddy-filled East Sea Current that contains weak anticyclonic gyres in the Ulleung and Yamato Basins. It accelerates toward the Yamato Rise and against the eastern coast of the JES. The published numerical model solutions show several historical circulation features but fail to capture many of the new structures described by the drifter data.

The HANBIT device is a simple mirror-type device of which the length, radius, and magnetic field are about 5 m, 0.18 m, and 0.1-0.3 T, respectively, in the central cell. In HANBIT, two antenna systems are used for the plasma production, heating, and MHD stabilization; one is the slot antenna located near the center region with the maximum power of 500 kW and the typical frequency of 3.5 MHz, and the other DHT antenna located near the mirror throat with the maximum power of 100 kW and the frequency of 3.75 MHz. Recent experimental studies in HANBIT indicate that the slot antenna system can produce stable, high-density plasmas in apparently two different regimes; one is the fast wave regime with the ratio w/Wci∼2 and the other is the slow wave regime with w

TiO2-coated granular activated carbon was employed for the removal of toxic microcystin-LR from water. High surface area of the activated carbon provided sites for the adsorption of microcystin-LR, and the adsorbed microcystin-LR migrated continuously onto the surface of TiO2 particles which located mainly at the exterior surface in the vicinity of the entrances of the macropores of the activated carbon. The migrated microcystin-LR was finally degraded into nontoxic products and CO2 very quickly. These combined roles of the activated carbon and TiO2 showed a synergistic effect on the efficient degradation of toxic microcystin-LR. A continuous flow fluidized bed reactor with the TiO2-coated activated carbon could successfully be employed for the efficient photocatalytic of microcystin-LR.

The mission of Korea Superconducting Tokamak Advanced Research (KSTAR) project is to develop an advanced steady-state superconducting tokamak for establishing a scientific and technological basis for an attractive fusion reactor. Because one of the KSTAR mission is to achieve a steady-state operation, the use of superconducting coils is an obvious choice for the magnet system. The KSTAR superconducting magnet system consists of 16 Toroidal Field (TF) coils and 14 Poloidal Field (PF) coils. Internally-cooled Cable-In-Conduit Conductors (CICC) are put into use in both the TF and PF coil systems. The TF coil system provides a field of 3.5 T at the plasma center and the PF coil system is able to provide a flux swing of 17 V-sec. The major achievement in KSTAR magnet-system development includes the development of CICC, the development of a full-size TF model coil, the development of a coil system for background magnetic-field generation, the construction of a large-scale superconducting magnet and CICC test facility. TF and PF coils are in the stage of fabrication to pave the way for the scheduled completion of KSTAR by the end of 2006.

HANBIT is a magnetic mirror confinement device. Recent physics experiments have been mainly focused on identifying discharge characteristics and on getting stable plasma production and operation modes, by using a 500 kW slot antenna system at a fixed RF frequency of 3.5 MHz and varying discharge conditions such as fueling rate, RF power, and B-field intensity in central cell. Two distinct operation modes are found to be very sensitive to the RF power as well as the ratio of the RF frequency to the ion cyclotron frequency. A MHD interchange mode of m = -1 is clearly observed and the stabilizing mechanism can be explained by the sideband coupling theory.

A review is made of circulation and currents in the southwestern East/Japan Sea (the Ulleung Basin), and the Korea/Tsushima Strait which is a unique conduit for surface inflow into the Ulleung Basin. The review particularly concentrates on describing some preliminary results from recent extensive measurements made after 1996. Mean flow patterns are different in the upstream and downstream regions of the Korea/Tsushima Strait. A high velocity core occurs in the mid-section in the upstream region, and splits into two cores hugging the coasts of Korea and Japan, the downstream region, after passing around Tsushima Island located in the middle of the strait. Four-year mean transport into the East/Japan Sea through the Korea/Tsushima Strait based on submarine cable data calibrated by direct observations is 2.4 Sv (1 Sv = 10 6 m 3 s −1 ). A wide range of variability occurs for the subtidal transport variation from subinertial (2–10 days) to interannual scales. While the subinertial variability is shown to arise from the atmospheric pressure disturbances, the longer period variation has been poorly understood. Mean upper circulation of the Ulleung Basin is characterized by the northward flowing East Korean Warm Current along the east coast of Korea and its meander eastward after the separation from the coast, the Offshore Branch along the coast of Japan, and the anticyclonic Ulleung Warm Eddy that forms from a meander of the East Korean Warm Current. Continuous acoustic travel-time measurements between June 1999 and June 2001 suggest five quasi-stable upper circulation patterns that persist for about 3–5 months with transitions between successive patterns occurring in a few months or days. Disappearance of the East Korean Warm Current is triggered by merging the Dok Cold Eddy, originating from the pinching-off of the meander trough, with the coastal cold water carried Southward by the North Korean Cold Current. The Ulleung Warm Eddy persisted for about 20 months in the middle of the Ulleung Basin with changes in its position and spatial scale associated with strengthening and weakening of the transport through the Korea/Tsushima Strait. The variability of upper circulation is partly related to the transport variation through the Korea/Tsushima Strait. Movements of the coastal cold water and the instability of the polar front also appear to be important factors affecting the variability. Deep circulation in the Ulleung Basin is primarily cyclonic and commonly consists of one or more cyclonic cells, and an anticyclonic cell centered near Ulleung Island. The cyclonic circulation is conjectured to be driven by a net inflow through the Ulleung Interplain Gap, which serves as a conduit for the exchange of deep waters between the Japan Basin in the northern East Sea and the Ulleung Basin. Deep currents are characterized by a short correlation scale and the predominance of mesoscale variability with periods of 20–40 days. Seasonality of deep currents is indistinct, and the coupling of upper and deep circulation has not been clarified yet.

We report the (bare) surface redox-reaction rate constant k that was determined, along with the chemical diffusivity D , by a conductivity relaxation technique on Al-doped single crystal and undoped polycrystal BaTiO 3− δ as a function of oxygen activity in its range of −16≤log a O 2 ≤0 at elevated temperatures of 800–1100 °C. It takes a value in the range of −4 k /cm s −1 )≤−1, which is even larger than that of the oxides that are considered best as oxygen membranes. It has been found that the surface reaction step grows more rate controlling as the electronic transference number gets smaller or the electronic stoichiometric composition ( δ ≈0) is approached. The oxygen potential drop due to the surface reaction was estimated by an oxygen concentration cell technique. The oxygen potential drop grows larger as the stoichiometric composition is approached, that is in accord with the variation of k against oxygen activity.

Hot electrons have been created in the plug section of the Hanbit tandem mirror in order to allow a test of high-m ballooning stability provided by a high-β hot-electron plasma in a tandem mirror. A rectangular microwave cavity was built to confine the energy from a 2-kW 14-GHz klystron. The cavity was equipped with a diamagnetic loop, a skimmer probe, and bremsstrahlung windows. An end-loss probe has been added in the cusp section in order to study the hot-electron mirror losses from the plug. The end-loss probe contains a Silicon PIN diode that is used to detect the x-rays from fast electrons striking a tantalum radiator. The end-loss probe was scanned radially to determine the radius and radial width of the hot-electron distribution ring for two different magnetic fields. A clear ring is observed for both magnetic fields. Bremsstrahlung measurements have shown the presence of a hot-electron plasma in the plug with an electron temperature in the range of 60 to 120 keV. The temperature with the optimum magnetic field is ∼ 100 keV. Diamagnetic measurements give the total stored energy. Stored-energy measurements combined with the radial dimensions determined by the end-loss detector were used to give the value of beta with assumptions on the plasma length. The average beta value is much less than 1% due to the low power and short heating time.

Oxygen nonstoichiometry (δ) of 1 m/o Mn-doped polycrystalline BaTiO3−δ has been measured as a function of oxygen partial pressure in the range of 10−16≤PO2/atm≤0.1 at elevated temperatures (900≤T/°C≤1100) by a solid-state coulometric titration technique. The extent of nonstoichiometry of Mn-doped BaTiO3 is much larger than that of undoped BaTiO3, which is attributed to defect-chemical role of Mn as acceptors. The nonstoichiometry isotherms indicate that Mn-ions change their valence from +4 (or MnTix) to +3 (or MnTi′) to +2 (or MnTi″) with decreasing PO2.

인공위성의 본체 및 탑재체 제작에 사용되고 있는 구성품 재질 12점을 수집하여 가시광 영역에서 지상 분광실험을 수행한 결과 위성체 구성품 재질별로 분광반사율과 분광유형이 뚜렷이 차이를 보였고 위성체의 재질별 분류 및 식별이 가능하였다. 인공위성 재질의 지상 분광실험 결과는 운용초기에 있는 인공위성이나 우주잔해물을 실제로 분광관측하여 얻은 자료와 비교함으로써 대상물의 재질유형 및 재질구성비, 그리고 크기와 중량을 예측하는데 활용될 수 있을 것이다. 【Laboratory tests have been carried out for investigation of the spectroscopic characteristics at visible wavelength of 12 common satellite materials used in satellite bus and payload. The obtained spectral data show that the materials can be classified and identified since their spectral features and albedos distinctly differ among them. It is suggested that the result of the laboratory tests for the satellite materials can be used for the predictions of material types, material composition ratios, sizes, and masses in comparison with the spectral data obtained from observations of new satellites or space debris.】

Photoinduced electron transfer from chlorophyll-a throughtheinterface of dipalmitoylphosphatidylcholine (DPPC) headgroup of the lipid bilayers was studied with electron magnetic resonance (EMR). The photoproduced radicals were identified with electron spin resonance (ESR) and radical yields of chlorophyll-a were determined by double integration ESR spectra. The formation of vesicles was identified by changes in measured λmax values from diethyl ether solutions to vesicles solutions indirectly, and observed directly with SEM and TEM images. The efficiency of photosynthesis in model system was determined by measuring the amount of chlorophyll-a radical yields which were obtained from integration of ESRspectra.

The first phase of the HANBIT project that started in 1996, is ending this year. The goal of the first phase is to establish a decent experimental facility based on the HANBIT mirror device and to ...

The singularity system to represent two circular cylinders poised under different ambient flow fields is considered in the present research. The singularity system, composed of a series of singularities, has to be truncated for numerical calculations. A rational criterion to determine how many terms of this series should be retained to maintain the prescribed accuracy is provided through analysis of the converging property of the series. A particular emphasis is put on how to deal with the discrete vortex model of a boundary layer, this possibility being the basis for the development of a tool to simulate vortex shedding from a structure composed of two circular cylinders. The principle in obtaining the present singularity system can be applied to more-than-two-cylinders structures. Only the series becomes more complex with an increase in the number of cylinders. [S0098-2202(00)01704-1]

This work presents an analysis of the dynamic behaviour of a HRSG (heat recovery steam generator) during start-up. A calculation program based on a quasi-steady method is constructed. A typical high-pressure HRSG is designed conceptually and analysis is performed to examine the influence of the gas inlet condition of the HRSG on its start-up behaviour. Effects of the gas turbine operation mode and the gas bypass are analysed. In addition, the water level control during start-up, which is one of the most important facts in the real plant operation, is simulated. Through a parametric calculation, the effect of the control parameters on the start-up behaviour is analysed and examples of optimum control are demonstrated. Copyright © 2000 John Wiley & Sons, Ltd.

Polycystic ovary syndrome (PCOS) is the most common cause of anovulation in women. Previous studies suggest that the pathogenesis of PCOS may involve interrelated abnormalities of the insulin-like growth factor (IGF) and ovarian steroidogenesis systems. We investigated this hypothesis in fasting serum samples from 140 women with PCOS (age, 27.4 +/- 0.4 yr; body mass index, 26.3 +/- 0.5 kg/m2; mean +/- SEM). IGF-related parameters were also studied in a group of normoovulatory women (n = 26; age, 26 +/- 4 yr; body mass index, 23.6 +/- 4.3 kg/m2). For the PCOS group, the mean testosterone (T) level was 2.5 +/- 0.1 nmol/L, and it was significantly correlated with LH (r = 0.41; P < 10(-6)), estrone (r = 0.33; P = 0.016), estradiol (r = 0.18; P = 0.04), and androstenedione (AD; P < 10(-6)), but not with dehydroepiandrosterone sulfate (P = 0.71), a marker of adrenal steroidogenesis. T and AD were also related to total ovarian follicle number and ovarian size, as previously found with normoovulatory women (1). There were no differences between the PCOS subjects and the normoovulatory group for total IGF-I, IGF-II, or IGF-binding protein-3 (IGFBP-3). However, IGFBP-1 levels were significantly decreased in the PCOS group (1.0 +/- 0.2 vs. 7.3 +/- 1.1 ng/mL; P < 0.001) and were inversely correlated with serum insulin levels (r = -0.50; P < 10(-8)). Serum levels of free IGF-I (fIGF-I) were elevated (5.9 +/- 0.3 vs. 2.7 +/- 0.3 ng/mL; P < 0.001) in inverse relation with IGFBP-1 (r = -0.31; P = 0.046). Serum fIGF-I levels were related to total follicle number (r = - 0.35; P < 10(-4)) and to the ratio of sex hormone-binding globulin to T (r = -0.23; P = 0.009). However, these relationships were not independent of other variables. Despite the more than 2-fold elevation in fIGF-I levels, significant relationships between fIGF-I and markers of ovarian steroidogenesis (T, AD, estradiol, and estrone) could not be demonstrated. In conclusion, although we confirmed correlations between LH and hyperandrogenemia and have found abnormalities in the IGF system in a large cohort of PCOS subjects, a direct relationship between hyperandrogenism and the IGF system could not be shown. Previous studies suggest that elevated LH and hyperinsulinemia lead to excess ovarian androgen synthesis in PCOS and that the intraovarian IGF system is important for normal follicle development and may be important in the arrested state of follicle development in PCOS. However, the data presented in this cross-sectional study suggest that insulin-related changes in circulating IGFBP-1 and subsequent elevation of fIGF-I reflect insulin resistance and have little enhancing effects on ovarian steroidogenesis in this disorder.

The Hanbit device' is a magnetic mirror machine which has a central cell, one anchor cell and one plug cell. The Hanbit device has been involved in a series of experiments on stabilization of the MHD flute type mode including stability experiments with a divertor. We have undertaken investigations to see if the Kinetic Stabilizer (KS) of R. F. Post 2-5 can stabilize the MHD instability. According to the theory, by locating a stabilizing plasma pressure on the field lines at a region with a strong second derivative and large radius in the expanding field region outside the mirrors, the main plasma in the mirror central cell in regions with unfavorable field line curvature can be stabilized. The Hanbit KS uses microwave produced plasmas on field lines in the cusp tank region. Two coils on the cusp tank are configured to produce expanding field lines with a large positive radius of curvature. A 5-kW 2.45 GHz magnetron is used to produce the stabilizing electron cyclotron resonant heated (ECRH) plasma pressure in this region. Details of the experimental arrangement and stabilizing plasma parameters were previously reported. 6 For normally terminating plasmas, a reduction in the instability duration has been observed and the range of density where the instability occurs has decreased. However, for higher density plasmas which disrupt due to an m=-1 instability, a prevalent m=+1 instability is removed while the duration of the m=-1 instability is increased.

The heavy metal mercury elicits a genetically restricted, anti-nucleolar autoantibody response that targets fibrillarin, a 34-kDa protein component of many small nucleolar ribonucleoprotein particles. The mechanisms by which a toxin such as mercury elicits an autoantibody response that predominantly targets a single intracellular protein autoantigen remain uncertain, but may be prefaced by mercury gaining access to the intracellular environment. Mercury-induced cell death was associated with loss of fibrillarin antigenicity and modification of the molecular properties of fibrillarin as revealed by aberrant migration under nonreducing conditions in SDS-PAGE. Addition of mercury to isolated nuclei also resulted in aberrant migration of fibrillarin, but not other nuclear autoantigens. The sensitivity of the HgCl2-induced modification of fibrillarin to 2-ME, iodoacetamide, and hydrogen peroxide suggested interaction of mercury with the two cysteines in the fibrillarin sequence. This was confirmed by mutation of the cysteines to alanines, which abolished the aberrant migration of fibrillarin in the presence of HgCl2. The modification of the molecular structure of fibrillarin by mercury reduced immunoprecipitation by anti-fibrillarin autoantibodies, pointing to unmodified fibrillarin as the B cell Ag and implicating mercury-modified fibrillarin as the source of T cell antigenicity. These observations demonstrate for the first time that an environmental toxin can alter the physicochemical properties of an autoantigen and may help to explain the antigenic specificity of mercury-induced murine autoimmunity.

CoMo bimetallic nitride catalysts were prepared by temperature-programmed reduction of CoMo oxides with flowing ammonia, and the effects of cobalt addition on the thiophene hydrodesulfurization (HDS) reaction were investigated. MoO3 transformed into Mo2N, while cobalt oxide was just reduced to Co metal rather than Co nitride. When Co was added to Mo, the surface area decreased significantly but the new bimetallic nitride phase of Co3Mo3N was produced. The addition of Co could improve the HDS conversion, and the high specific activity of the bimetallic nitride catalyst was believed to be related with the new Co3Mo3N phase.

Continuing the experiments reported previously, 1 , 2 additional microwave power has been applied to the plug region of Hanbit in order to increase the stored energy and beta of the hot-electron plasma created there. Two new 1.5-kW VA-806 klystrons at 7.67 GHz and 7.87 GHz have been used in conjunction with the existing 2-kW CPI klystron at 14 GHz. The plasma is created in order to provide a high-beta ring to stabilize the Hanbit central cell plasma against ballooning instabilities. An array of Hall probes mounted on the outside of the Hanbit plug cavity was installed to measure the axial profile of the Bz fields. The total stored energy was measured by diamagnetic loops and the radial location of the plasma was determined by a Si-PIN diode detector measuring the energetic electron end loss. All three measurements were to be used to determine the radial and axial location of the plasma, the plasma volume, the stored energy, and hence the plasma beta. However, the Bz signal was too small to measure and the diamagnetic signal was smaller than previously found. The ring was found to be very wide and not adequate to stabilize the central cell plasma.

The compatibility of vancomycin hydrochloride and famotidine in 5% dextrose injection stored at two temperatures was studied. Vancomycin hydrochloride and famotidine were reconstituted and diluted with 5% dextrose injection to form an admixture with a famotidine concentration of 0.2 mg/mL and a vancomycin concentration of 5 mg/mL. The admixture was stored in 100-mL vented intravenous containers in the dark at 4 and 25 deg C; three containers were stored at each temperature. A 2-mL sample was taken from each container after six and 12 hours and 1, 3, 5, 7, 10, 12, and 14 days of storage and visually inspected, tested for pH and assayed by a developed stability-indicating high performance liquid chromatographic method. Triplicate samples were prepared for each storage condition. No color change, precipitation or cloudiness was observed in any sample at any time during the study. Vancomycin 5 mg/mL and famotidine 0.2 mg/mL in admixtures in 5% dextrose injections are stable for 14 days at 4 and 25 deg C.

Insulin-like growth factors (IGFs) and their specific regulatory binding proteins (IGFBPs) are postulated to play a key role in bone metabolism. To date, IGFBP-2 through -6 have been characterized in bone cell systems. In this study we focused on IGFBP-1. Primary cultures of normal human osteoblasts derived from trabecular bone (hOB cells) expressed low levels of IGFBP-1 messenger RNA (mRNA), as determined by Northern analyses. Treatment of hOB cells with 1 microM cortisol or 100 nM dexamethasone for 20 h stimulated IGFBP-1 mRNA expression 5-fold and increased levels of immunoassayable IGFBP-1 in the conditioned medium 3-fold. Estradiol and progesterone had no effect. IGFBP-1 expression was not observed in U-2, TE-85, or MG-63 human osteosarcoma cell lines or in normal human fibroblasts. Insulin (1-100 nM) potently inhibited both basal and glucocorticoid-stimulated IGFBP-1 expression in hOB cells. Insulin had little or no effect on steady state levels of the other IGFBP mRNA. A monoclonal antibody to the insulin receptor blocked insulin binding to insulin receptors and completely prevented insulin-induced suppression of IGFBP-1. In summary, we have documented IGFBP-1 mRNA and protein expression in normal nontransformed human osteoblastic cells. This expression was stimulated by glucocorticoids and inhibited by insulin in a manner similar to IGFBP-1 regulation in hepatocytes. Insulin acts through insulin receptors on hOB cells. We postulate that IGFBP-1 produced by osteoblasts in vivo can modulate local actions of IGF on bone formation in response to changes in glucocorticoid and insulin concentrations.

Insulin-like growth factor (IGF-I) action is influenced by circulating as well as tissue levels of its binding proteins. Because serum IGF binding protein-1 (IGFBP-1) levels have been found to be decreased in patients with polycystic ovary syndrome (PCOS), we tested the hypothesis that regulation of IGFBP-1 secretion may be different in patients with PCOS compared with normal women. We studied 15 normal ovulatory women and 15 women with PCOS of similar age (21 ± 1 and 22 ± 1 years, respectively). All subjects were studied after an overnight fast between days 5–8 after spontaneous or progestin-induced menses. Perturbations included the administration of insulin intravenously, maintenance of a euglycemic clamp, and, in a subsequent cycle, the administration of a long-acting somatostatin analogue (octreotide, 100 μg) given subcutaneously. Blood samples were collected before treatment, every 15 minutes for 6 hours after insulin, and every 30 minutes for 3 hours after octreotide administration. Serum levels of IGF-I, IGFBP-1, IGFBP-3, and insulin were measured by specific immunoassays. Compared with the controls, patients with PCOS had significantly higher insulin levels, similar IGF-I and IGFBP-3 levels, and significantly lower IGFBP-1. INsulin did not change serum IGF-I levels in either group, although a significant decrease in IGFBP-1 levels occurred in normal women but ot in patients with PCOS. Octreotide treatment also did not change serum IGF-I levels in either group, but serum insulin levels decreased significantly and IGFBP-1 levels increased significantly in both groups; this response was significantly greater in controls. Our data are compatible with the notion that regulation of IGFBP-1 is altered in women with PCOS and that several factors may be involved.