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Superconducting and antiferroquadrupolar (AFQ) transitions in a Pr-based compound PrRh2Zn20 have been found to occur simultaneously at Tc = TQ = 0.06 K. The superconducting transition manifests itself by zero resistance and large diamagnetic susceptibility. The specific heat exhibits a Schottky anomaly peaking at 14 K, and magnetization curves measured at 2 K show anisotropic behaviors. The analysis of these data indicates that the crystalline electric field ground state ofthe trivalent Pr ion is the non-Kramers T3 doublet with the quadrupolar degrees of freedom. A sharp peak in the specific heat at 0.06 K has been attributed not to the superconducting transition but to the AFQ transition because the ordering temperature TQ decreases in B || [100] but increases in B || [110] and B || [11||] with increasing B up to 6 T. This anisotropic behavior of TQ(B) can be well explained by a two-sublattice mean-field calculation, which corroborates the AFQ ordered state below TQ. The entropy release at TQ is only 10% of R In 2 expected for the Γ3 doublet, suggesting possible interplay between the quadrupolar degrees of freedom and the superconductivity. [ABSTRACT FROM AUTHOR]

Abstract: A high-density cold exciton gas is generated in a harmonic potential trap by two-photon resonance excitation of CuO at 2K. Strongly localized light signal is observed at the bottom of the potential trap when the exciton density exceeds 10 cm. The possibility of bosonic stimulation of excitons from the trap rim to the bottom is discussed in connection with the origin of the light signal. [Copyright &y& Elsevier]

Abstract: κ-, ι- and λ-Carrageenans were degraded by irradiation with gamma rays in the solid state, gel state or solution with various doses in air at ambient temperature. The molecular weights obtained were in the range of 10.5×104 to 0.8×104 of narrow molecular weight distribution. The chemical structural changes of carrageenans were accompanied by appearance of UV absorbance peak at 260nm and a characteristic FT-IR band at 1728cm-1. Due to radiation-induced desulfation, carrageenan oligomer has lower sulfate content. From comparison of radiation degradation yield (Gd), susceptibility to degradation of the three types of carrageenans in aqueous form follows the order of λ>ι>κ which could have been influenced by their conformational state. The oligomer obtained from κ-carrageenan with molecular weight of 1.0×104 showed a strong growth promotion effect on potato in tissue culture. Degradation of κ-carrageenan solution using vessel-type low energy electron beam accelerator (LEEB) (250kV, 10mA) was investigated. LEEB irradiation reduced the molecular weight of carrageenan though the electron beams have a depth penetration range of less than 3mm in distilled water. [Copyright &y& Elsevier]

Emission spectroscopy is performed to study the optical transitions between electronic bands of SWCNs formed in AlPO4−5 (AFI) crystal. Strong visible emission is observed under laser light illumination at room temperature. The emission is excited by the light polarized along the c-axis and its polarization is also along this direction. On the other hand, non-linear emission is observed under the resonant excitation of the lowest absorption band of SWCNs. The emission is excited by the light polarized along the c-axis, but it shows the polarization perpendicular to the c-axis. The polarization character is discussed on the basis of the selection rules of the optical transitions predicted by the full line-group symmetry of SWCNs. [Copyright &y& Elsevier]

The density distribution of cold exciton clouds generated into a strain-induced potential well by two-photon excitation in Cu2O is studied at 2 K. We find that an anomalous spike, which can be interpreted as accumulation of the excitons into the ground state, emerges at the potential minimum. The accumulation can be due to stimulated scattering of cold excitons, mediated by acoustic phonon emission. The possibility of the formation of the thermodynamic Bose–Einstein condensate of paraexcitons is discussed. [Copyright &y& Elsevier]

Eight plants of the putative double monosomic addition line (DMAL, 2n =20) were developed by crossing a monosomic chromosome addition line of radish [f(A)-type monosomic addition line (MAL) (2n =19)] carrying the f chromosome of Brassica rapa (2n =20, AA) with another [e(C)-type MAL (2n =19)] having the echromosome of Brassica oleracea (2n =18, CC). The homoeological relationships between the two alien chromosomes were investigated by morphological, cytogenetic and random amplified polymorphic DNA (RAPD) analysis. Seventeen morphological traits that were not present in the radish cv. `Shogoin' were observed in both MALs and these traits were substantially exhibited in DMAL plants. At the first metaphase of pollen mother cells (PMCs), the two parental MALs showed a chromosome configuration of 9II + 1I, demonstrating impossibility of recombination between the R and the added chromosomes. The DMALs formed 10II in approximately 73% of PMCs, with one bivalent showing loose pairing between two chromosomes differing in size. In an attempt to identify the two MALs by RAPD-specific markers using 26 selected random primers, 13 and 20 bands were specific for the f(A)-type and the e(C)-type MALs, respectively; 12 bands were common to both MALs (26.7%). In conclusion, the f chromosome of B. rapa is homoeologous to the e chromosome of B. oleracea . The genetic domain (genes) for 17 morphological traits are linked to each homoeologous chromosome bearing 27% of the corresponding RAPD markers. [ABSTRACT FROM AUTHOR]

Upgrading and utilization of carbohydrates such as chitosan, sodium alginate, carrageenan, cellulose, pectin have been investigated for recycling these bio-resources and reducing the environmental pollution. These carbohydrates were easily degraded by irradiation and various kinds of biological activities such as anti-microbial activity, promotion of plant growth, suppression of heavy metal stress, phytoalexins induction, etc. were induced. On the other hand, some carbohydrate derivatives, carboxymethylcellulose and carboxymethylstarch, could be crosslinked under certain radiation condition and produce the biodegradable hydrogel for medical and agricultural use. [Copyright &y& Elsevier]

A lower limit for the value of χ(3) associated with the two-photon resonance of the Γ1 biexcitons in CuCl at 1.6 K is found to be 5.4×10-5 esu. The upper bound of the two-photon resonance width is ΔE=0.02 meV. Broadening of the resonance occurs for light intensities I0>103 W/cm2. [ABSTRACT FROM AUTHOR]

New polymer gel dosimeters consisting of 2-hydroxyethyl methacrylate (HEMA), triethylene glycol monoethyl ether monomethacrylate (TGMEMA), polyethylene glycol 400 dimethacrylate (9G), tetrakis (hydroxymethyl) phosphonium chloride as an antioxidant, and gellan gum as a gel matrix were prepared. They were optically analyzed by measuring absorbance to evaluate a dose response. The absorbance of the polymer gel dosimeters that were exposed to 60Co γ-rays increased with increasing dose. The dosimeters comprising HEMA and 9G showed a linear increase in absorbance in the dose range from 0 to 10 Gy. The dose response depended on the 9G concentration. For others comprising HEMA, 9G and TGMEMA, the absorbance of the polymer gel dosimeters drastically increased above a certain dose, and then leveled off up to 10 Gy. The optical variations in these polymer gel dosimeters were also induced by x-irradiation from Cyberknife radiotherapy equipment. Furthermore, the exposed region of the latter polymer gel dosimeter exhibited a thermo-responsive behavior. [ABSTRACT FROM AUTHOR]

Aim: To verify the usefulness of a sliding scale of imaging parameters to reduce radiation exposure during chest interventional radiology (IR), and to identify factors that increase radiation exposure in order to obtain acceptable computed tomography (CT)-fluoroscopy image quality. Materials and Methods: The institutional review board approved this retrospective study, for which the need for informed consent was waived. Interventional radiologists determined the optimal CT-fluoroscopy imaging parameters using the sliding scale based on the radiation exposure dose. The imaging parameters were changed from those generating low radiation (120 kV/10 mA, 1.2 mGy/s) to others generating higher radiation exposure until acceptable image quality was obtained for each procedure. Validation of the imaging parameter sliding scale was done using regression analysis. Factors that increase radiation exposure were identified using multiple regression analysis. Results: In 125 patients, 217 procedures were performed, of which 72 procedures (33.2%, 72/217) were performed with imaging parameters of minimum radiation exposure, but increased radiation exposure was necessary in 145 (66.8%, 145/217). Significant correlation was found between the radiation exposure dose and the percentage achievement of acceptable image quality (R(2) = 0.98). Multivariate regression analysis showed that high body weight (p < 0.0001), long device passage (p < 0.0001), and lesions above the aortic arch (p = 0.04) were significant independent factors increasing radiation exposure. Conclusion: Although increased radiation exposure dose might be necessary to obtain acceptable chest CT-fluoroscopy images depending on the patient, lesion, and procedure characteristics, a sliding scale of imaging parameters helps to reduce radiation exposure. [ABSTRACT FROM AUTHOR]

Abstract: The optimum plant growth promoting effect in irradiated κ-carrageenan is known to be of Mw<10,000. This is obtained by irradiating κ-carrageenan at a dose of 100kGy in solid and at 2kGy in 1% aqueous solution. Kappa carrageenan irradiated at these doses was fractionated at different Mw ranges. The isolated fraction with a Mw of 3–10kDa was analyzed by NMR. The chemical shifts of 13C and 1H spectra indicated that the basic functional structure of κ-carrageenan (alternating d-galactose-4-sulfate and 3,6-anhydro-d-galactose dimer) remains intact at a Mw of 3–10kDa. No radiolytic products were detected at this range. [Copyright &y& Elsevier]

Abstract: Blend hydrogels based on the carboxymethyl cellulose (CMC) and carboxymethyl chitosan (CMCts) were prepared by γ-irradiation of a high concentrated CMC/CMCts aqueous solution. Properties of the hydrogels, such as gel fraction, swelling ratio, gel strength, and metal adsorption for Pb and Au were investigated. The gel fraction increased with increasing dose, while the swelling ratio decreased with increasing it. The obtained blend hydrogels had high adsorption performance which was controlled by adjusting the composition of CMC/CMCts. [Copyright &y& Elsevier]

Photo-induced electric current modulation is studied in AFI-SWCNs systems by visible and near infra-red laser light at room temperature. Remarkable polarization anisotropy in the modulation is observed. λ-dependence of the polarization anisotropy is analyzed by a simple model based on the optical anisotropy observed in absorption spectra. [Copyright &y& Elsevier]

Epitaxial growth of CeO[sub 2](001) thin films on Si(001) substrates was achieved by electron beam evaporation. Reflection high-energy electron diffraction and cross-sectional high-resolution transmission electron microscopy established the formation of an epitaxial CeO[sub 2](001)/Si(001) structure with a cube-on-cube configuration. The epitaxial structure had to be formed at a temperature below 200 °C with a Si(001)-2x1, 1x2 reconstructed surface, and it could be formed even at room temperature. In order to improve the crystallinity, homoepitaxial growth conditions at a higher temperature with a high oxygen flow rate were also investigated. Homoepitaxy of ceria grown on a 5-nm-thick initial layer was demonstrated by θ/2θ-scan and φ-scan of x-ray diffraction. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Effects of dose rate and liner energy transfer (LET) on the optical property of a polymer gel dosimeter irradiated with swift heavy ions were investigated. The polymer gel dosimeters that consist of 2-hydroxyethyl methacrylate, polyethylene glycol dimethacrylate, and tetrakis(hydroxymethyl)phosphonium chloride with radiation-crosslinked hydroxypropyl cellulose gel matrix were prepared. The dosimeters were irradiated with 150 MeV/u He ions, 290 MeV/u C ions, and 500 MeV/u Fe ions at HIMAC, and then were optically analyzed by using a UV–Vis spectrophotometer. Absorbance of the irradiated dosimeters increased with an increase in the dose up to 10 Gy. The absorbance at the dose of 5 Gy decreased with increasing dose rate in all of the heavy ions. The dosimeter irradiated with Fe ions exhibited the lowest dose response of the absorbance. It was found that the sensitivity of the dosimeters decreased with increasing dose rate as well as LET of the incident heavy ions. [ABSTRACT FROM AUTHOR]

Aim: To verify the usefulness of a sliding scale of imaging parameters to reduce radiation exposure during chest interventional radiology (IR), and to identify factors that increase radiation exposure in order to obtain acceptable computed tomography (CT)–fluoroscopy image quality. Materials and methods: The institutional review board approved this retrospective study, for which the need for informed consent was waived. Interventional radiologists determined the optimal CT–fluoroscopy imaging parameters using the sliding scale based on the radiation exposure dose. The imaging parameters were changed from those generating low radiation (120kV/10mA, 1.2mGy/s) to others generating higher radiation exposure until acceptable image quality was obtained for each procedure. Validation of the imaging parameter sliding scale was done using regression analysis. Factors that increase radiation exposure were identified using multiple regression analysis. Results: In 125 patients, 217 procedures were performed, of which 72 procedures (33.2%, 72/217) were performed with imaging parameters of minimum radiation exposure, but increased radiation exposure was necessary in 145 (66.8%, 145/217). Significant correlation was found between the radiation exposure dose and the percentage achievement of acceptable image quality (R 2 =0.98). Multivariate regression analysis showed that high body weight (p <0.0001), long device passage (p <0.0001), and lesions above the aortic arch (p =0.04) were significant independent factors increasing radiation exposure. Conclusion: Although increased radiation exposure dose might be necessary to obtain acceptable chest CT–fluoroscopy images depending on the patient, lesion, and procedure characteristics, a sliding scale of imaging parameters helps to reduce radiation exposure. [Copyright &y& Elsevier]

Abstract: The effects on N2O and N2 gas on the radiation degradation yield of aqueous kappa (κ-) carrageenan were investigated. The Gd of solution saturated with N2O solution was expectedly much higher than in air (1.7 and 1.2×10−7 molJ−1). On the other hand, a lower Gd of 1.1×10−7 molJ−1 was obtained from κ-carrageenan solution saturated with N2. The rate constant of reaction of OH radicals with sonicated and irradiated κ-carrageenan were determined using e-beam pulse radiolysis. The rate constant of OH interaction with sonicated κ-carrageenan decreased with decreasing molecular weight. On the other hand, the OH interaction with irradiated κ-carrageenan decreased but did not vary significantly with decreasing molecular weight. Metal ion (Na+) induced conformational transition into helical form decreased the rate constant of OH reaction with κ-carrageenan. Likewise, the Gd in aqueous form was affected by the conformational state of κ-carrageenan. The helical conformation gave a lower Gd (7×10−8 molJ−1) than the coiled conformation (Gd =1.2×10−7 molJ−1). [Copyright &y& Elsevier]

Abstract: The radiation degradation yield (G d) of kappa, iota and lambda carrageenans was compared in solid and in 1% aqueous solution in air at ambient temperature. G ds obtained in solid and aqueous form did not vary with the different types of carrageenan. The chemical structural changes of carrageenans were accompanied by appearance of UV absorbance peak at 260nm and a characteristic FT-IR band at 1728cm−1. Changes in the FT-IR finger print regions were observed at high doses of the aqueous solution. Radiation-induced desulfation increased the acidity of the carrageenans. The number of reducing end groups increased with dose with greater susceptibility in κ-carrageenan. [Copyright &y& Elsevier]

OBJECTIVE:To assess the validity of self-reported height and weight in a Japanese workplace population, and to examine factors associated with the validity of self-reported weight.DESIGN:Comparison of self-reported height and weight with independent measurement.SUBJECTS:In total, 4253 men and 1148 women aged 35–64 y (mean measured body mass index (BMI): 23.3 kg/m2 in men, 21.9 kg/m2 in women) were included in the study.MEASUREMENTS:Self-reported height and weight were obtained by a self-administered questionnaire. Measured height and weight were based on annual health checkups. Sex, age, measured BMI, and the presence of hypertension, diabetes, and hyperlipidemia were examined as potential factors associated with the accuracy of self-reported weight.RESULTS:Self-reported height and weight were highly correlated with measured height and weight for men and women (Pearson’s r for men and women: 0.979 and 0.988 in height, 0.961 and 0.959 in weight, 0.943 and 0.950 in BMI, respectively). For men, mean differences±2 s.d. of height and weight were 0.078±2.324 cm and −0.034±5.012 kg, respectively, and for women 0.029±1.652 cm and 0.024±4.192 kg, respectively. The prevalence of obesity with BMI ≥25 kg/m2 based on self-reported data (23.6 and 11.5% for men and women, respectively) was slightly smaller than that based on measured data (24.9 and 12.4%, respectively). Specificity and sensitivity, however, were quite high for both men and women (sensitivity was 85.8 and 85.2%, and specificity was 97.0 and 98.9%, respectively). The subjects with higher measured BMI significantly underestimated their weight compared with those with smaller BMI after adjustments for age in men and women. Furthermore, the presence of diabetes in men and age in women affected self-reported weight. Neither the presence of hypertension nor hyperlipidemia was associated with reporting bias.CONCLUSION:The self-reported height and weight were generally reliable in the middle-aged employed Japanese men and women. However, it should be remembered that self-reported weight was biased by actual BMI and affected by age and the presence of diabetes.International Journal of Obesity (2005) 29, 1093–1099. doi:10.1038/sj.ijo.0803012; published online 31 May 2005 [ABSTRACT FROM AUTHOR]

We have investigated atomic dynamics of caged compound LaRu2Zn20 by the measurements of specific heat C and inelastic x-ray scattering (IXS). The lattice part of the specific heat Clat divided by T³,Clat/T³, shows a broad peak at around 15 K, which is reproduced by two Einstein modes with characteristic temperatures of θE1=35 K and θE2=82 K, respectively. IXS measurements along the [111] and [110] directions reveal weakly dispersive phonon modes at 3 meV (35 K) and 7 meV (80 K), respectively, whose values agree with the values of θE's. The first-principles calculation has assigned the 3 meV phonon modes as the optical modes of Zn atoms located at the middle of two La atoms, which is likely to lead to the structural instability. [ABSTRACT FROM AUTHOR]