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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.

Globally, many parts of fire emissions are driven by deforestation. However, few studies have attempted to evaluate deforestation and vegetation degradation fires (DDF) and predict how they will change in the future. In this study, we expanded a fire model used in the Community Land Model to reflect the diverse causes of DDF. This enabled us to differentiate DDFs by cause (climate change, wood harvesting, and cropland, pastureland, and urban land‐use changes) and seasonality. We then predicted the state of fire regimes in the 2050s and 2090s under RCP 2.6 and RCP 6.0 scenarios. Our results indicate that the area affected by global total fires will decrease from the current 452 to 211–378 Mha yr−1 in the 2090s under RCP 6.0 and to 184–333 Mha yr−1 under RCP 2.6, mainly due to socioeconomic factors such as population and economic growth. We also predict that DDF will decrease from the current 73 million hectares per year (Mha yr−1) to 54–66 Mha yr−1 in the 2090s under RCP 6.0 and 46–55 Mha yr−1 under RCP 2.6. The main contributor to these decreases in DDF burned area was climate change, especially the increasing of precipitation. The impact of future land use change on future DDF was similar or slightly lower than present‐day. South America, Indonesia, and Australia were identified as high‐risk regions for future DDF, mainly due to the expansion of wood harvest and pastureland. Appropriate land and fire management policies will be needed to reduce future fire damage in these areas.

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.

Topology optimization technique utilizes constant element densities as design parameters. Finally, optimal distribution contours of the material densities between voids (0) and solids (1) in design domain represent the determination of topology. It means that regions with element density values become occupied by solids in design domain, while there are only void phases in regions where no density values exist. Therefore the void regions of topology optimization results provide design information to decide appropriate depositions of web-opening in structure. Contrary to the basic objective of the topology optimization technique which is to obtain optimal topology of structures, this present study proposes a new idea that topology optimization results can be also utilized for decision of proper web-opening’s position. Numerical examples of linear elastostatic structures demonstrate efficiency of methodological design processes using topology optimization in order to determinate the proper deposition of web-openings., {"references":["Eon, D. S., Suh, H. J. and Kim, Y. B. (1985) An Experimental Study on\nthe Reinforced Concrete Beams with Web Opening. Journal of\nArchitectural Institute of Korea, 5 (2), 337-340","Koo, H. S. (1998) An Experimental Study on Characteristics of\nReinforced Concrete Beams with the Rectangular Opening. Journal of\nArchitectural Institute of Korea, 14 (7), 11-19","Bendsøe, M. P. and Kikuchi, N. (1988) Generating Optimal Topologies in\nOptimal Design using a Homogenization Method. Computer Methods in\nApplied Mechanics and Engineering, 71 (1), 197-224","Bendsøe, M. P. (1989) Optimal Shape Design as a Material Distribution\nProblem. Structural Optimization, 1, 193-202","Mlejnek, H. P. (1992) Some Aspects of the Genesis of Structures.\nStructural Optimization, 5, 64-69","Yang, R. and Chang, C. (1994) Optimal Topology Design using Linear\nProgramming. Computers and Structures, 52, 265-275","Haug, E. J., Choi, K. K. and Komkov, V. (1986) Design Sensitivity\nAnalysis of Structural Systems. Academic Press, Orlando, New York","Sigmund, O. (2001) A 99 Line Topology Optimization Code written in\nMatlab. Structural Multidisciplinary Optimization, 21, 120-127."]}

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.