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Natural rubber latex (NRL) is mainly used for traditional industrial products, but currently, its target application is continuously expanding into tissue engineering. Here, we have presented the chondrogenesis ability of NRL nanoparticles against human mesenchymal stem cells (hMSCs). The effective gene expression of in vitro chondrogenesis of hMSCs with administration of NRL was confirmed as revealed by the chondrogenic gene expression analysis. We have successfully for the first time fabricated the cartilage/NRL biocomposites via hMSC spheroid formation, where the administration of NRL nanoparticles exhibited the mechanically stable structure with hard surface structure in the spheroid.

In recent years climate change and other anthropogenic factors have contributed to increased wildfire frequency and size in western United States forests. This research focuses on the evaluation of spatial and temporal changes in evapotranspiration (ET) following the 2011 Las Conchas Fire in New Mexico (USA) using the Operational Simplified Surface Energy Balance Model (SSEBop ET). Evapotranspiration is coupled with soil burn severity and analyzed for 16 watersheds for water years 2001–2014. An average annual decrease of 120 mm of ET is observed within the regions affected by the Las Conchas Fire, and conifers were converted to grassland a year after the fire. On average, the post-fire annual ET in high, moderate, and low burn severity is lower than pre-fire ET by approximately 103–352 mm, 97–304 mm, and 91–268 mm, respectively. The ratio of post-fire evapotranspiration to precipitation (ET/P) is statistically different from pre-fire conditions (α = 0.05) in nine of the watersheds. The largest decrease in ET is approximately 13–57 mm per month and is most prominent during the summer (April to September). The observed decrease in ET contributes to our understanding of changes in water yield following wildfires, which is of interest for accurately modeling and predicting hydrologic processes in semi-arid landscapes.

Post-fire hydrologic research typically focuses on the first few years after a wildfire, leading to substantial uncertainty regarding the longevity of impacts. The time needed for hydrologic function to return to pre-fire conditions is critical information for post-fire land and water management decisions. This is particularly true in Mediterranean climates, where water is scarce and in high demand, and the severity and area burned by wildfires are increasing. In part, uncertainty about hydrologic recovery is due to lack of a consistent definition or interpretation of what constitutes “recovery.” Here, we systematically reviewed empirical studies from Mediterranean climates with at least three years of post-fire hydrologic data with the objectives of (a) assessing the recovery period, (b) identifying a definition of post-fire hydrologic recovery, (c) demonstrating a simple analytical approach to aid in assessment of recovery, and (d) outlining research needs and opportunities to better quantify post-fire recovery. We assessed the hydrologic effects reported in 38 sites that were monitored for 3–20 years. Eighteen sites were considered recovered within seven years; however, the recovery time was inconsistent across sites and was not related to location, response variable, or study design. The likelihood of recovery within the study period also decreased with increasing proportion of the watershed area burned. Importantly, we have also proposed a standardized definition and an approach to quantifying hydrologic recovery that may facilitate cross-study comparisons and a deeper understanding of recovery. Specifically, we propose hydrologic recovery has occurred when a specific post-fire hydrologic function or condition of interest returns to the 95% confidence interval of the pre-fire condition. In support of this definition, we have demonstrated applying this simple approach to assess recovery and presented future research topics to improve our understanding of long-term post-fire catchment responses. In addition to the need for more studies that quantify hydrologic responses farther into the post-fire period, understanding post-fire changes in soil structural and hydraulic properties through time will improve our mechanistic understanding of post-fire hydrologic responses and recovery.

Across the globe, wildfires are increasing in frequency and magnitude under a warming climate, impacting natural resources, infrastructure, and millions of people every year. At the same time, human encroachment into fire-prone areas has increased the potential for ignition, as well as risks and damages to human communities. In an era of intensifying human activities on Earth – the “Anthropocene” – societal interactions with post-fire landscapes are becoming commonplace. Yet, theories regarding post-fire impacts derived from individual disciplines no longer apply in cases where human interactions are intense. A holistic approach that accounts for interactions between natural and human systems is necessary to understand the altered dynamics of post-fire landscapes. Focusing on the intersection of fire, water, and society, this paper explores an integrative research framework to couple post-fire fluvial and human processes. We review trends in wildfires and growing impacts on humans, how fluvial processes and systems are altered by wildfires, and the potential hazards for human settlements. This review forms a basis for integrating societal concerns, such as vulnerability, economic impacts, and management responses. We then link disciplinary questions into broad interdisciplinary research through an integrative framework. The 2012 Waldo Canyon Fire (Colorado, USA) provides an illustrative case with intense human interactions, both during and after the fire, to formulate critical questions within the integrative framework. Utilizing emergent integrative conceptual frameworks and tools will assist scholars in meeting the challenges and opportunities for broad collaboration, which are necessary to understand and confront wildfires characteristic of the “Anthropocene.”

The thermal diffusivity of reactor irradiated (U,Gd)O 2 fuels has been measured, for burn-ups from 33 to 97 GWd tHM − 1 and for irradiation temperatures from 670 to 1580 K. Measurements under thermal annealing cycles were performed in order to investigate the recovery of the thermal conductivity as a function of temperature. The analysis of the results showed a lower thermal conductivity for (U,Gd)O 2 when compared to UO 2 , with similar effects of the burn-up and irradiation temperature. A correlation for the thermal conductivity could be proposed on the basis of that for UO 2 presented in an earlier work, which describes the separate effects of soluble fission products, of fission gas frozen in dynamical solution and of radiation damage.

The current study investigates the spatial and temporal dynamics of post-fire vegetation and the subsequent influence on seasonal and annual hydrologic responses in chaparral-dominated watersheds. Post-fire climatology, burn severity, slope aspect, and vegetation behavior are evaluated for two basins burned during the 2003 Old Fire in the San Bernardino Mountains in Southern California. Climate and discharge data are used to evaluate seasonal and annual variability of post-fire hydrologic fluxes. Data obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) are used to estimate Enhanced Vegetation Index (EVI) and differenced Normalized Burn Ratio (dNBR). A Savitzky–Golay filtering technique and an integrated EVI annual fraction are utilized to assess vegetation recovery under a range of potential controls. Vegetation recovery is highly variable in both watersheds and is related to slope aspect (solar and water availability), initial biomass levels, and burn severity. South and west facing slopes show higher pre-fire EVI (biomass) and significant loss of vegetation cover after fire. Vegetation in both watersheds responds to an extreme wet season during the second post-fire year, however recovery rates are not sustained. North and east aspects show the quickest biomass gain relative to pre-fire conditions by the end of the study period (WY 2010), while the west and south slopes show lower biomass recovery. High burn severity areas show the slowest recovery across all slope aspects, with these regions just approaching 90% of pre-fire biomass by the end of the seven-year post-fire period. The variable rate of vegetation recovery across the watersheds results in significant changes in annual and seasonal discharge throughout the post-fire period. Runoff ratios remain elevated in both systems and there is increased dry season flow for much of the study period, indicating that plant water consumption and flowpaths are not back to pre-fire behavior by the end of WY 2010.

In order to understand the properties of ion tracks and the microstructural evolution under accumulation of ion tracks in UO 2 , 100 MeV Zr 10+ and 210 MeV Xe 14+ ions irradiation examinations have been done at a tandem accelerator facility of JAEA-Tokai, and it has been observed the microstructure by means of a transmission electron microscope (TEM) and a scanning electron microscope (SEM) in CRIEPI. Comparison of the diameter of ion tracks between UO 2 and CeO 2 under irradiation with 100 MeV Zr 10+ and 210 MeV Xe 14+ ions at room temperature clarify that the sensitivity on high density electronic excitation of UO 2 is much less than that of CeO 2 . By the cross-sectional observation of UO 2 under irradiation with 210 MeV Xe 14+ ions at 300 °C, elliptical changes of fabricated pores that exist till ∼6 μm depth and the formation of dislocations have been observed in the ion fluence over 5 × 10 14 ions/cm 2 . The drastic changes of surface morphology and inner structure in UO 2 indicate that the overlapping of ion tracks will cause the point defects, enhance the diffusion of point defects and dislocations, and form the sub-grains at relatively low temperature.

In order to clarify, from the electronic structure, the origin of the appearance of the tri-valent Ce state in irradiated cerium dioxide with swift heavy ions, we performed comprehensive first-principles calculations on various defective structures in cerium dioxide. The calculated results show that an oxygen mono-vacancy or an oxygen Frenkel pair can induce two tri-valent Ce states neighboring the oxygen vacancy. The calculation of the oxygen Frenkel pair further reveals that an interstitial oxygen atom that moves from the lattice position and an oxygen atom on the lattice can form a dimer that behaves as an oxygen molecule of negative di-valence. This bonding state can also produce excess electrons and the tri-valent Ce state in cerium dioxide.

In light water commercial reactors, extensive change of grain structure was found at high burnup ceramic fuels. The mechanism is driven by bombardment of fission energy fragments and studies were conducted by combining accelerator based experiments and computer-science. Specimen of CeO2 was used as simulation material of fuel ceramics. With swift heavy ion (Xe) irradiation on CeO2, with 210 MeV, change of valence charge and lattice deviation of cations were observed by XPS and XRD. Combined irradiations of Xe implantation and swift heavy ion irradiation successfully produced sub-micrometer sized sub-grains, similar as that observed in commercial fuels. Studying components of mechanism scenarios, with first principle calculations using the VASP code, we found stable hyper-stoichiometric defect structures of UO2+x. Molecular dynamics studies revealed stability of Xe planar defects and also found rapid transport mode of oxygen-vacancy clusters.

We studied the migration dynamics of oxygen point defects in UO2 which is the primary ceramic fuel for light-water reactors. Temperature accelerated dynamics simulations are performed for several initial conditions. Though the migration of the single interstitial is much slower than that of the vacancy, clustered interstitial shows faster migration than those. This observation gives us important insight on the formation mechanism of high-burnup restructuring, including planar defects and grain sub-division (the rim structure), found in UO2.

In order to understand the properties of ion tracks and the microstructural evolution under accumulation of ion tracks and Xe ions in CeO2, 70–210 MeV Xe10∼14+ ions irradiation examinations and pre-implantations of 240 keV Xe ions have been done at a tandem accelerator facility and an ion implanter facility of JAEA-Tokai. The microstructure observations were performed by means of a transmission electron microscope (TEM) and a scanning electron microscope (SEM) in CRIEPI. Measurements of the diameter of ion tracks with the irradiation temperature, between room temperature and 800 °C, clarify that the prominent changes of ion tracks are hardly observed up to 800 °C. By cross-sectional observation, it becomes clear that the threshold electronic stopping power of ion track formation is around 15–16 keV/nm in case of Xe ions irradiation. 210 MeV Xe14+ ion irradiations cause a surface roughness on CeO2 in the ion fluence range between 5 × 1014 ions/cm2 and 1 × 1015 ions/cm2.

In order to simulate the effects of high energy fission products on high-burnup UO 2 nuclear fuel pellets, CeO 2 thin films and bulk specimens were irradiated with 200 MeV Xe ions. Effects of the irradiation were studied by using Extended X-ray Absorption Fine Structure (EXAFS) measurement and X-ray photoelectron spectroscopy (XPS) at synchrotron radiation facilities. The EXAFS spectra for the irradiated thin films near the Ce K-edge show the formation of the oxygen deficiency around Ce ions. XPS Spectra show that the valence state of Ce atoms is changed from intrinsic Ce 4+ to Ce 3+ state by the irradiation. As such irradiation effects appear even for low fluence irradiation, the experimental result suggests that the oxygen deficiency and the change in Ce valence state are due to high-density electronic excitation induced by the 200 MeV Xe ions.

Ratios of equilibrium charge-state yields for singly to doubly ionized He-3 ions at an energy of 420 MeV were measured using the Grand Raiden magnetic spectrometer at RCNP. Targets with atomic numbers of 6, 12, 28, 40, 50 and 82 were used. It is found that theoretical calculations for atomic electron-capture and stripping cross sections, which have been successful in describing the data up to beam energies of 200 MeV, are also applicable at this higher energy. However, where at the lower energies the stripping cross sections were calculated with a combination of models by Bohr and Gillespie, the best description of the data at E(He-3) = 420 MeV is obtained when using only the model by Gillespie. The experimental results are also compared with calculations using the code CHARGE, originally developed for fast, heavy (Z > 29) projectiles, to test the extrapolation to low-Z projectiles. It is found that the code underestimates the production of singly-charged He-3 ions, in particular for heavier target nuclei. (c) 2007 Elsevier B.V. All rights reserved.

In order to understand the functional maturation of the CNS, it is essential to first describe the functional maturation of sensory processing. We have approached this topic by following the ontogenetic patterning of neural circuit formation related to cranial and spinal sensory input using voltage-sensitive dye imaging. In previous studies, we have described the functional maturation of synapses in brainstem/midbrain neural circuits. Here, we elucidate the functional maturation of forebrain circuits by investigating neural networks related to the olfactory nerve (N. I) of chicken embryo. In the isolated N. I-olfactory bulb-forebrain preparation, application of electrical stimulation to N. I elicited excitatory postsynaptic potential (EPSP)-related slow optical signals in the olfactory bulb. The slow signal was mainly mediated by glutamate, and was easily fatigued with repetitive stimuli because of the immaturity of synapses in the embryonic CNS. Ontogenetically, the slow signal was detected from the 6-day embryonic stage, suggesting that functional synaptic connections between N. I and olfactory bulb emerge around this stage. In addition, from the 8-day embryonic stage, another response area was discriminated within the forebrain, which corresponded to the higher-ordered nucleus of the olfactory pathway. In comparison with our previous studies concerning the functional development of other cranial nerve-related sensory nuclei in the embryonic brainstem and midbrain, these results suggest that the olfactory pathway is functionally generated in the early stages of development when neural networks related to other visceral and somatic sensory inputs are also in the process of developing.

In order to understand the formation mechanism of a crystallographic re-structuring in the periphery region of high-burnup nuclear fuel pellets, named as “rim structure”, information on the accumulation process of radiation damage and fission products (FPs), as well as high-density electronic excitation effects by FPs, are needed. In order to separate each of these processes and understand the high-density electronic excitation effects, 70–210 MeV FP ion (Xe 10–14+ , I 7+ and Zr 9+ ) irradiation studies on CeO 2 , as a simulation of fluorite ceramics of UO 2 , have been done at a tandem accelerator of JAEA-Tokai and the microstructure changes were determined by transmission electron microscope (TEM). Measurements of the diameter of ion tracks, which are caused by high-density electronic excitation, have clarified that the effective area of electronic excitation by high-energy fission products is around 5–7 nm ϕ and the square of the track diameter tends to follow linear function of the electronic stopping power ( S e ). Prominent changes are hardly observed in the microstructure up to 400 °C. After overlapping of ion tracks, the elliptical deformation of diffraction spots is observed, but the diffraction spots are maintained at higher fluence. These results indicate that the structure of CeO 2 is still crystalline and not amorphous. Under ion tracks overlapping heavily (>1 × 10 15 ions/cm 2 ), surface roughness, with characteristic size of the roughness around 1 μm, is observed and similar surface roughness has also been observed in light-water reactor (LWR) fuels.

The low frequency (∼300 MHz) and low-temperature (0.4 K) ESR were performed in the γ-phase of p-NPNN, which is considered to be as a quasi-one-dimensional ferromagnet above the antiferromagnetic ordering temperature (0.65 K without a static magnetic field). Below 0.6 K, we succeeded in observing the antiferromagnetic resonance (AFMR) for the first time. The frequency–field relation is well reproduced by the two-sublattice model with orthorhombic anisotropy. In addition, we measured magnetic torque using small single crystal, which has the dimension of 0.25 × 0.10 × 0.10 mm3. A spin–flop transition and AF-paramagnetic (AF-P) transition are observed at 470 and 2100 G at 0.4 K, respectively. Both AFMR and magnetic torque measurements indicate that the spin-easy axis is almost parallel to the direction to phenyl ring from the ONCNO fragments.

Research of the effect of space environment on an ecosystem consisting of plants and animals is essential when they are to be positively used in space. Although there have been experiments on various organisms under space environment in the past, they mainly studied the effect of space environment on an individual organism or a single species. Microcosm is drawing attention as an experimental material of an ecosystem consisting of multiple species. The object in this research is to understand the nature of this network system called ecosystem. Thus, a mixed microorganism culturing system consisting of three types of microorganisms which form a minimum food chain system as a closed ecosystem (chlorella as the producer, bacteria as the decomposer, and rotifer as the consumer) was taken for the subject, on which to research the universal characteristics of ecosystems. From the results of experiments under the terrestrial environment, formation of colonies, which is an ecological structure, has been observed at its mature stage. The organisms form an optimal substance circulation system. Therefore, formation of colonies in simulation models is important. Many attempts have been made to create ecosystem models. For example, the Lotka-Volterra model forms a simultaneous equation with the differential equation expressing predator and prey relationship and many numerical calculations have been conducted on various ecosystems based on expanded L-V models. Conventionally, these top-down methods have been used. However, since this method only describes the average concentration of organisms that are distributed uniformly throughout the system and cannot express the spatial structure of the system, it was difficult to express ecosystem structures like colonies and density distributions. In actual ecosystems, there is heterogeneity in the number of individuals and in substance density, and this is thought to have great significance in ecosystems. Consequently, an individual-based model was used that applies rules to predator-prey relationship, suppression, production, self suppression, etc., of each species. It enabled the emergence of the overall system only by its local rules, and it was possible to reproduce colony generation. In addition, the transition and the ratio of populations for each species match well with experimental results.

A multi-pellet injector system has been developed as a fundamental fueling tool for the Large Helical Device (LHD). Since a primary goal of the LHD project is demonstration of steady-state high-temperature plasmas, highly reliable and reproducible performance is prerequisite for the LHD pellet injector. The helium Gifford-McMahon (GM) cycle cryogenic refrigerator and conventional pipe-gun mechanism have been employed along with these requirements. Since the triple point temperature of hydrogen is lower than those of isotopes; deuterium and tritium, a careful and steady temperature control is necessary in pellet formation. The amount of propellant gas has been minimized by small reservoir to reduce heat load and inflow into the plasma vacuum chamber. Both robustness and flexibility have been realized by using the programmable logic controller combined with GUI on WindowsNT. The pellet injector has demonstrated continuous hundreds of injection without any fail and has been applied for the LHD experiment successfully.

An impurity diffusion technique using an excimer laser was studied for the p-type doping of CdTe. A thin layer of Na 2 Te was evaporated on the CdTe crystal, and laser irradiation decomposed the Na 2 Te and diffused Na atoms into the Cd site. The resistivity of the top layer of the crystal decreased to below 1 Ωcm and showed p-type conductivity. This technique is applied for fine-patterned p-type doping on the crystal by laser irradiation through a shadow mask. Furthermore, p-i-n CdTe diodes were fabricated for an X-ray imaging device by growing an iodine-doped n-CdTe layer on one side of the crystal and fine-patterned p-type doping on the other side. This device showed good diode properties with a well-saturated reverse bias current and good imaging properties.

A system for liquefying a gaseous sample has been constructed in order to study the neutron-capture reaction of a sample using keV neutrons. It consists of a cryostat with a refrigeration system, a temperature-control system, a gas-handling system, and a vacuum system. It can liquefy all gaseous samples (except for He). Since we use a small amount of a compound of light elements, such as polycarbonate and acrylic resin, as the vacuum cell and the sample cell, we can measure the small neutron capture cross section of a sample having a few μb with a high S/N value by employing a prompt γ-ray detection method. The system has been shown to operate continuously for a long-term experiment using natural Ne gas without any problem.

A BWR design UO2 fuel irradiated to a burnup of 7.9% FIMA was selected for a careful calculational and experimental analysis because the rod experienced an unusual power history: it had two high power periods at 1.7% FIMA and between 4 and 5% FIMA causing increased fuel temperatures and thus increased gas release and damage recovery. As a consequence, two parameters generally considered to be important for grain subdivision (rim structure formation) were locally different from normal fuel, i.e. fission gas inventory and extent of radiation damage. Histories of temperature, fission rate and fission gas release were calculated at different radial positions. Microstructure observations (TEM, SEM) revealed the typical high burnup grain subdivision process (polygonization) which extended to a maximum of 1.65 mm (r/r0 = 0.73) from the pellet surface inwards. For this radial position, the calculations yielded a local temperature of 1200°C and predicted that more than half of the fission gas was released during the second high power period for this radial position. The results give thus information on the importance of the fission gas inventory for the burnup threshold of restructuring.

The high burnup LWR UO2 fuels show a notable micro-structural change around the pellet outer zone which is called the rim structure. It is observed at temperatures as low as 400°C so that fission track and cascade mixing could be the key mechanism. SEM observation revealed that the structure primarily appears on free surfaces of UO2, indicating that strong sink for point defects may play a big role. And as generic observations, increase of lattice parameter indicates extensive amounts of vacancies are stored in high burnup fuel, which may induce the restructuring interacting with dislocations of high density at high burnup. Considering these observations a model of reaction-diffusion process of defects with irradiation induced transport is proposed. The equations are investigated numerically. The model indicates that an instability starts when the dislocation network starts intensive interaction with vacancy flux which is modified by interstitial diffusion between spatial segments. It appeared to be similar to the Turing type instability which indicates that the rim structure formation is one kind of the self-organizing processes of open reaction-diffusion systems.

Transmission and high resolution scanning electron microscopy were used to analyze the microstructure of the periphery of a UO2 pellet irradiated to a cross-section average burnup of 7.9% FIMA, with a period of increased temperature at about half the final burnup. Local burnups at the pellet surface reached nearly 23% FIMA. In this rim region the original grains of about 10 μm diameter were subdivided into about 104 subgrains of 0.15 to 0.30 μm diameter. The spread in subgrain orientation was small ( 1 mm. The size of the subgrains was found to be largely independent of depth.

The magnetic interactions in β-phase p-NPNN (p-nitrophenyl nitronyl nitroxide), a prototype genuine organic ferromagnet, have been studied by simultaneous measurements of magnetic heat capacity and susceptibility under hydrostatic pressures. A drastic reduction of the Curie temperature from 0.6 K at ambient pressure to 0.35 K at 7.2 kbar has been observed. This makes a significant contrast to the pressure-induced enhancement of the Neel temperature of organic antiferromagnets. A lowering of the magnetic lattice dimensionality is also observed at temperatures slightly above the Curie temperature under pressure. These observations are interpreted in terms of the virtual charge transfer mechanism.

The de Haas - van Alphen measurements of the deuterated molecular conductor (DMe-DCNQI) 2 Cu have been carried out to investigate the Fermi surface and the possibility of the mass enhancement of the conduction electrons near the insulating phase. The Fermi surfaces and the cyclotron masses of the deuterated samples which show the drastic metal - insulator - metal transition are found to be the same as those of the undeuterated sample. The fact shows that the additional mass enhancement due to many body effects is absent near the insulating phase.

The effect of initial mixture temperature on the experimentally measured detonation cell size for hydrogen-air-steam mixtures at 0.1 MPa has been investigated. Experiments were carried out in a 10-cm-inner-diameter, 6.1-m-long heated detonation tube with a maximum operating temperature of 700 K and spatial temperature uniformity of ±14 K. Detonation cell size measurements provide clear evidence that the effect of hydrogen-air initial gas mixture temperature, in the range 300–650 K, is to decrease cell size and, hence, to increase the sensitivity of the mixture to undergo detonations. The effect of steam content, at any given temperature, is to increase the cell size and, thereby, to decrease the sensitivity of stoichiometric hydrogen-air mixtures. The hydrogen-air detonability limits for the 10-cm-inside-diamter test vessel, based upon the onset of single-head spin, decreased from 15% hydrogen at 300 K down to about 9% hydrogen at 650 K. The experimental detonation cell size data were correlated using a Zel'dovich-von Neumann-Doring (ZND) model for the detonation using detailed chemical-kinetic reaction mechanisms. The proportionality constants used to scale the reaction zone length calculations from the ZND model varied from 30 to 51 for the hydrogen-air cell size data at 650 and 300 K, respectively.

The mechanism of the antiatherogenic activity of n -3 polyunsaturated fatty acids is not well understood. In these studies, we studied the metabolism of unsaturated fatty acids in murine macrophage-like J774A.1 cells. The major metabolic pathway of 18- and 20-carbon chain unsaturated fatty acids in these cells is the sequence of 2-carbon chain elongation, successive two steps of Δ 8 - and Δ 5 -desaturation, and additional elongation. Polyunsaturated fatty acids, arachidonic acid [20:4 ( n −6)] and eicosapentaenoic acid [20:5 ( n −3)], are elongated into 22:4 ( n −6) and 22:5 ( n −3) fatty acids, respectively. Accumulation of 22:4 ( n −6) and 22:5 ( n −3) fatty acids shows that J774A.1 cells have an active chain elongation activity, but lack Δ 4 -desaturase activity. Furthermore, J774A.1 cells demonstrated almost negligible Δ 6 -desaturase activity. Enrichment of the membrane lipids of J774A.1 cells with polyunsaturated fatty acids, arachidonic acid [(20:4 ( n −6)] and eicosapentaenoic acid [(20:5 ( n −3)], increased membrane fluidity and decreased the uptake of acetylated low density lipoprotein.

Magnetic properties of a stable organic biradical, meta-phenylene bis(α-nitronyl nitroxide) (abbreviated as m-BNN) were investigated. The molecular ground state of m-BNN is found to be triplet (S=1) from the solution EPR measurements. The temperature dependence of the product of paramagnetic susceptibility and temperature, ξpT, of the single crystal of m-BNN exhibits anomalous stationary behavior with decreasing temperature as a result of intermolecular exchange interactions. From the analysis based on the structure of magnetic energy spectrum in a solid state, the formation of unusual magnetic energy gaps in the crystal is deduced. An organic triradical, the 1,3,5-tri-substituted form (TNN), was also studied. By solution EPR measurements, this molecule is shown to have the quartet ( S= 3 2 ground state. A polycrystalline sample of the triradical exhibits a broad susceptibility maximum around 16 K. The value of the susceptibility extrapolated to 0 K is nonzero. This indicates the gapless nature of the triradical solid, in contrast to the gap formation in the biradical.

Magnetization isotherms up to 5.5 T and temperature dependence of magnetic susceptibility down to 1.8 K of the organic neutral radicals, 3- and 4-quinolyl nitronyl nitroxide and 2,6-pyridinediyl bis(nitronyl nitroxide), are described. 3-quinolyl nitronyl nitroxide exhibit ferromagnetic intermolecular interaction with the Weiss constant Θ = 0.27 K, whereas 4-quinolyl nitronyl nitroxide shows antiferromagnetic intermolecular interaction with the exchange coupling constant J/k = −7.8 K. This significant difference between the magnetic properties of two compounds are discussed in terms of their crystal structures. The temperature dependence of product of paramagnetic susceptibility and temperature, χ p T, of a biradical 2,6-pyridinediyl bis(nitronyl nitroxide) shows a plateau at low temperatures in addition to the usual plateau observed in the high-temperature region. This peculiar behavior is interpreted in terms of the multi-spin system associated with a combined effect of ferro- and antiferro-magnetic couplings.

The changes in electrical resistivity caused by electrolytically charged hydrogen in a series of palladium - rare earth (RE) solid solution alloys (RE  Sc, Gd, Dy, Tb, Ho, Er, Yb, Lu) were investigated in the low hydrogen concentration region of the α phase, together with measurements of the electrode potential.

In order to understand the nature of the mixed state, the critical current density Jc of Nb/NbZr multilayers was measured as a function of magnetic field H and of the angle between H and the film plane at the temperatures where the superconducting order parameter is localized in the Nb layers. In the parallel fields, which are perpendicular to the current J, the Jc-H curves show a peak at H=Hmax. The observed angular dependence of Jc below and above Hmax can be explained by the 3D stepwise vortex model and the 2D pancake vortex model, respectively. These results indicate that a dimensional crossover in the mixed state occurs at Hmax. This crossover may be the cause of the field dependence of Jc which is an increasing function of H below Hmax.