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The magnetic shielding of high-temperature superconducting (HTS) current leads is proposed as a means of achieving high permeability and low thermal conductivity between superconducting magnets and HTS current leads. To this end, a structure consisting of Bi-Sr-Ca-Cu pipes and ferrite powder padding was constructed. Upon insertion of HTS leads, the critical current increase and magnetic flux densities of the innermost HTS pipe were measured.

Abstract. Tuning the ion release ability of bioactive materials is one of the key factors for bone repair and regeneration. Calcium (Ca2+), magnesium (Mg2+), and silicate ions were reported to enhance the activity of bone-forming cells. In this work, the dissolution behavior of magnesium- and silicate-doped calcium carbonate (vaterite), denoted as MgSiV, embedded in three kinds of biodegradable polymers in Tris buffer solutions (TBS) were examined to find an effective ion releasing system. Poly(L-lactic acid) (PLLA) and poly(D,L-lactide-co-glycolide) (PDLLG, lactide:glycolide = 75:25 or 50:50; denoted as PDLLG75 and PDLLG50, respectively) were chosen as the matrix polymers. The Mg2+ and silicate ions were released rapidly within 3 d of soaking. Continuous release of Ca2+ ions from the composites induced the formation of aragonite on the film surfaces in the presence of Mg2+ ions. The amount of ions released from the MgSiV-PLLA composite was lesser than those released from the PDLLG-based composites. The fast degradation of PDLLG50 induced a decrease in the pH of TBS. The MgSiV-PDLLG75 composite exhibited a rapid release of Mg2+ ions, a continuous release of Ca2+ ions, and a controlled release of silicate ions with no reduction in the pH of TBS. Such release phenomena are caused by the formation of pathways for ion release, originating from the water uptake ability of PDLLG75. [ABSTRACT FROM AUTHOR]

The operating stability of the solid electrolyte component is one of paramount importance in the design of all-solid-state Li ion batteries. In this work, we investigated the origin of capacity fading during the charge process of an air-isolated Li ion battery with a garnet Li6.625La3Zr1.625Ta0.375O12 (LLZrTaO) solid electrolyte, a Li metal anode, and a LiFePO4 + carbon (LFP + C) active cathode material. Cyclic voltammetry measurements of the fabricated Li/LLZrTaO/(LLZrTaO + C) and Li/LLZrTaO/Al cells revealed a rise and an absence, respectively, of oxidation current which points to the garnet oxide electrolyte being decomposed via a reaction with carbon. XRD patterns of the solid electrolyte at post-charging showed no detectable impurity phases, suggesting that the decomposition product(s) is (are) likely made up of light elements. Based on first-principles calculations, the decomposition route may involve the formation of defective garnet by Li removal, oxygen release, and formation of products such as Li2CO3 and possibly of CO2; formation of the latter product is facilitated at elevated operating temperatures. Among the evaluated base garnet compounds (Li5+xLa3M2O12, with M: Nb Ta for x = 0 and M: Zr, Ti, Hf for x = 2), Li7La3Hf2O12 is predicted to be the most stable against Li2CO3 formation. A strong correlation has been determined between stability at charging and the electronegativity of the M cation, that is, the smaller the M electronegativity, the more stable is the garnet compound against carbon reactions. [ABSTRACT FROM AUTHOR]

Several inorganic ions released from bioceramics have been reported to stimulate osteogenic cell functions and to promote bone formation in body. In particular, a trace amount of silicate and calcium ions released from 45S5-type bioactive glass were reported to enhance several functions of human osteoblasts by many researchers. Additionally, magnesium ions have been reported to enhance cell adhesion to materials, along with the differentiation and biomineralization of osteoblasts. The aim of the present work was to examine combined effects of the three different ions, silicate, calcium and magnesium ions, on osteogenic cell functions. Mouse osteoblast-like cells were cultured in media containing different amounts of the three ions and their adhesion was evaluated. The rate of adhesion of the cells was significantly higher in the medium containing magnesium and silicate ions than that containing each single ion. Thus, the combined effects of the ions were observed for the cell adhesion. [ABSTRACT FROM AUTHOR]

Siloxane-containing vaterite (SiV) particles with spherical- to discoidal-morphologies were selectively prepared by a CO2 gas carbonation process in a methanol–acetone mixed solvent; they are intended for application as osteogenic devices in bone tissue engineering. Moreover, the c/ab-face ratio of vaterite was successfully tuned through the selection of methanol–acetone volume fractions. The solvent increased the supersaturation of CO32− ions and accelerated the crystal growth along the ab-axis in the presence of silsesquioxane. The particles released soluble silica species and calcium ions upon soaking in physiological pH buffer solution, which are expected to genetically stimulate osteoblasts to enhance bone reconstruction. An initial calcium ion release from the particles significantly decreased from 3.1 to 1.6 mmol L−1 as the c/ab-face ratio increased, while the composition of the particle and release profiles of soluble silica remained consistent. This demonstrated the possibility of tuning the calcium ion release from SiV particles by controlling the degree of crystalline plane orientation. [ABSTRACT FROM AUTHOR]

Abstract: One of the interesting arguments for a space impact mission to asteroid 3200 Phaethon is to create an artificial Geminid meteor shower. In this work we investigate the artificial shower’s dates of observability and dependence on ejecta velocity using dust trail theory. We find that when the dust ejecta velocities are 200m/s the artificial meteor showers start to be visible in 2204 and continue for about 30 years. If the dust ejecta velocity is 20m/s they only last 10 years from 2215 to 2225. Thus, the onset of artificial shower activity begins sooner and lasts longer with higher ejecta velocities. To produce an artificial meteor shower with 3200 Phaethon as the parent will require higher impact energy than the Deep Impact spacecraft delivered to 9P/Tempel 1. [Copyright &y& Elsevier]

Abstract: Fast-moving meteors such as Leonid meteors have two types of spectra. One is the main component composed of neutral atomic lines having low excitation temperature (∼5000K) and the other is the hot component composed of singly ionized lines such as Mg(II) and Ca(II) having high excitation temperature (∼10,000K). We observed the brightest fireball which appeared at, 03h47m54s UT of November 19, 2002 in the 2002 Leonid aircraft campaign. The neutral atoms composing the main component such as Mg(I), Fe(I), Ca(I) and Na(I) were identified in the wavelength range of 300–650nm. The singly ionized atomic emissions of Ca(II) and Mg(II) were also detected in this Leonid spectra during the temporal series of brightness of the fireball flight. So far, these emissions were considered to originate from the hot component. However, we found in several frames taken at the bright fireball during the period of the observation that the Ca(II) lines do not satisfy the hot-component condition even if the hot-component Mg(II) (448nm) emission was observed. This indicates that the Ca(II) lines do not always satisfy the hot-component condition. [Copyright &y& Elsevier]

In 1984 an INTELSAT antenna of 32 m of diameter was constructed at 3 370 metres above the sea level on the Peruvian Andes. At the time Entel Perú the Peruvian tele-communications company managed the antenna station, of almost 12 hectares in extension. In 1993 the government transferred the station to the private telecommunications company Telefónica del Perú. Since transoceanic fiber optics replaced radically satellite communications in 2002, a beautiful 32- metre parabolic antenna was finished its tele-communications mission and become available for other use. So in cooperation with the National Astronomical Observatory of Japan we began coordination to transform the antenna into a radio-telescope.Researches on interstellar medium around Young Stellar Objects (YSO) are possible using methanol maser that emits at 6.7 GHz, so initially we will monitor and survey maser sources at the southern sky. An ambient temperature receiver with Trx = 60 K was developed at Nobeyama Radio Observatory and is ready to be installed. The antenna will be controlled by the Field System FS9 software installed in a PC within a Linux environment. An interface between antenna and PC was developed at Kashima Space Research Center in Japan by Mr E. Vidal.In the near future S-band (2 GHz), X-band (8GHz), 12 GHz and 22 GHz observations are planned.The peculiar position and altitude of the Peruvian Radio Observatory will be useful for VLBI observations with the VLBA for astronomical observation and geodetic measurements. For Peru where few or almost non astronomical observational instruments are available for research, implementation of the first radio observatory is a big step to foster sciences at graduate and postgraduate levels of universities.Worldwide tele-communications antennas recently tend to finish their role as tele-communications antennas. Several of them are transformed into useful observational instruments. [ABSTRACT FROM PUBLISHER]

Abstract: Coccidioides posadasii is a dimorphic fungal pathogen that grows as a filamentous saprobe in the soil and as endosporulating spherules within the host. To identify genes specific to the pathogenic phase of Co. posadasii, we carried out a large-scale study of gene expression in two isolates of the species. From the sequenced Co. posadasii genome, we chose 1000 open reading frames to construct a 70-mer microarray. RNA was recovered from both isolates at three life-cycle phases: hyphae, presegmented spherules, and spherules releasing endospores. Comparative hybridizations were conducted in a circuit design, permitting comparison between both isolates at all three life-cycle phases, and among all life-cycle phases for each isolate. By using this approach, we identified 92 genes that were differentially expressed between pathogenic and saprobic phases in both fungal isolates, and 43 genes with consistent differential expression between the two parasitic developmental phases. Genes with elevated expression in the pathogenic phases of both isolates included a number of genes that were involved in the response to environmental stress as well as in the metabolism of lipids. The latter observation is in agreement with previous studies demonstrating that spherules contain a higher proportion of lipids than saprobic phase tissue. Intriguingly, we discovered statistically significant and divergent levels of gene expression between the two isolates profiled for 64 genes. The results suggest that incorporating more than one isolate in the experimental design offers a means of categorizing the large collection of candidate genes that transcriptional profiling typically identifies into those that are strain-specific and those that characterize the entire species. [Copyright &y& Elsevier]

The article studies the formation of titanium dioxide-rutile film using Nd:YAG laser. The scanning electron microscopy micrographs and energy dispersive spectrometry specta of the obtained films before and after the laser irradiation are shown. Biomimetic apatite-forming ability test of the films was performed by soaking at 100-milliliter of an aqueous solution with ion concentrations 1.5 times those of the simulated body fluid.

Examines the intergenic spacer region 1 (IGS1) of the nuclear rebosomal RNA gene in intersterility groups of the wood-rot fungus Heterobasidion annosum. Amplification of the rebosomal IGS regions; Location of the 5S rRNA gene; Restriction polymorphism in the amplified IGS1 locus.

A K-band receiver using cooled high-electron mobility-transistor (HEMT) amplifiers was developed at the Nobeyama Radio Observatory (NRO). Remarkable reduction of receiver noise temperature Trec was obtained when it was cooled down to cryogenic temperature. The lowest Trec of 75 K was obtained at 23.4 GHz. This low noise characteristic reveals that the cooled HEMT amplifier is promising as a sensitive receiver for radio astronomical observations. [ABSTRACT FROM AUTHOR]