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Optical fibres are currently being used for spacecraft systems as an essential component of fibre optic gyroscopes. This paper investigates the radiation effects on polarization maintaining fibre up to a total dose of 730 Gy. Comparisons are made between normal polarization maintaining fibre, pure silicon polarization maintaining fibre and photonic crystal polarization maintaining fibre test results. Results indicate that fibre gyros utilizing the pure silicon fibre will survive the long term radiation environment in space. Photonic crystal fibre shows a more complex behaviour with higher radiation induced attenuation level than expected from the pure silicon fibre structure. [ABSTRACT FROM AUTHOR]

Background: In presolar low-density graphite grains, an extraordinarily large 22Ne/20Ne ratio or even nearly pure 22Ne is found, pointing to the condensation of radioactive 22Na in grains. Supernovae and neon-rich novae are the main events that produce 22Na via the explosive hydrogen burning process. The 22Na(p, y)23Mg reaction is one of the key reactions that influences the 22Na abundance in ejecta. Purpose: The present work aims to explore the proton resonant states in 23Mg relevant to the astrophysical 22Na(p, γ)23Mg reaction. The determined 23Mg resonant parameters can be used to evaluate the 22Na(p, γ)23Mg reaction rate. Method: A low-energy 22Na radioactive ion beam is produced via the ¹H(22Ne, 22Na)n reaction, and used to measure the experimental excitation function of the 22Na + p resonant scattering with a conventional thick-target inverse kinematic method, R-matrix analysis is applied to deduce the 23Mg resonance parameters from the experimental excitation function. Results: Three proton resonance states in 23Mg are observed. Spins/parities and the proton partial widths are determined. The deduced excitation energies agree with the compiled values. Conclusions: The new spin and parity assignments allow us to perform a shell-model calculation of the γ widths of the 23Mg resonant states for the evaluation of the 22Na(p, γ)23Mg astrophysical reaction rate. The two s-wavc resonant states established in this work at 8.793 and 8.916 MeV in 23Mg, respectively, increase the total reaction rate by about 5% at a temperature greater than 2 GK. [ABSTRACT FROM AUTHOR]

We report an investigation of the local electronic structure and thermal diffusion mechanism of Zn0.8Mn0.2O epitaxial films by soft x-ray spectroscopy measurements. According to experimental results and establishment of the relationship between electronic structure and magnetic properties, the majority of Mn atoms are in substitutional sites in the as-grown film and the concentration of divalent Mn ions is found to be dominant in the ferromagnetic film, while after being annealed at 400 °C for 1 h, Mn atoms diffuse out of the ZnO lattice and accumulate in Mn-related secondary phases with high valence (+3 and/or +4) Mn ions. The formation of the secondary phases is correlated with the suppressed ferromagnetism (FM). The present results suggest that Mn2+ ions play a significant role for the FM in (Zn,Mn)O. [ABSTRACT FROM AUTHOR]

Abstract Micromagnetic simulations of the application of perpendicular field pulses to in-plane antiferromagnetically coupled (AFC) thin film disk media have been performed. Starting from a thermally relaxed state, application of a perpendicular field pulse to an in-plane medium results in fast in-plane precessional rotation. Our simulations indicate that 180° magnetization reversal of both AFC layers can be achieved by selecting the correct pulse duration, and that repeated reversal can be achieved with no significant decay of magnetization. Switching times as short as 8 ps are required, suggesting that ultra-high data rates could be achieved. Studies of the effect of pulse shape indicate that reversal and recording will be possible with the non-square pulses that would be expected from practical write heads. [ABSTRACT FROM AUTHOR]

Driven-dissipative quantum many-body systems have attracted increasing interest in recent years as they lead to novel classes of quantum many-body phenomena. In particular, mean-field calculations predict limit cycle phases, slow oscillations instead of stationary states, in the long-time limit for a number of driven-dissipative quantum many-body systems. Using a cluster mean-field and a self-consistent Mori projector approach, we explore the persistence of such limit cycles as short range quantum correlations are taken into account in a driven-dissipative Heisenberg model. [ABSTRACT FROM AUTHOR]

Purpose: The percentage isodose line to prescribe (RxIDL) in stereotactic radiosurgery (SRS) varies widely among institutions, possibly due to inconsistent evaluation parameters. Gradient index (GI), defined as the ratio of total volume receiving 50% of prescription dose (V0.5Rx) and target volume receiving prescription dose, is an important parameter to characterize a plan's dose falloff. It can be used as the criteria to determine optimal RxIDL, because clinically normal brain volume receiving 8-12Gy has been found to correlate to brain necrosis. This study aims to explore the optimal RxIDL for linac-based SRS using GI criteria. Methods: 17 patients with brain tumors were retrospectively studied using iPlan system (BrainLAB, Feldkirchen, Germany). MLC-based dynamic conformal arc technique was used for planning. For each patient, 6-8 plans with different RxIDLs were performed. All plans were normalized so that 95% of target volume receives prescription dose (typically 18Gy). The prescription isodose was calculated as the ratio of the prescription dose and the maximum dose in target volume. Different RxIDLs were achieved by changing MLC margin from -2mm to +2mm. GI was calculated for each plan and the one with minimal GI was considered as the optimal plan. Results: The optimal RxIDL appears to be between 50% and 75% for most cases. Generally as target volumes increases (from 0.15cm³ to 50.09cm³), GI decreases (from 6.3 to 2.4) and the optimal RxIDL shifts to higher values. Median optimal RxIDL is 53.1 +/-7.6% for target volumes less than 5cm³ and 74.0+/-1.9% for those larger than 5cm3. There is a relatively wide basin where GI is close to its minimum for target volumes greater than 2cm³. For target volumes smaller than 2cm³, large variation of optimal RxIDL (34.3%-64.4%) is observed. This is because target volume is small and GI is very sensitive to target's shape and location. However, because of the smaller volume, choosing a sub-optimal RxIDL will not change V0.5Rx much in absolute measurement. So if the minimal GI is at 50%, prescribing to 70% line might be still acceptable. The optimal MLC margin yielding the minimal GI is -0.5mm or -1 mm for most cases. Conclusions: The optimal RxIDL appears to be between 50% and 75% for the cases evaluated. Larger target volume tends to have a higher optimal RxIDL. The conclusion is based on the assumption that the minimal GI corresponds to the optimal RxIDL. Disclosure: No significant relationships. [ABSTRACT FROM AUTHOR]

Hetero-epitaxial thin films were obtained in PbTiO3/LaNiO3 thin films by using laser ablation for sequential deposition of each thin film. Structural variations were built to characterize the differences in local ferroelectric properties. For this study, 50 nm-thick-PTO thin films with (0 0 1) and (1 1 1) orientations were investigated. Piezoresponse force microscopy (PFM) was used to investigate the local ferroelectricity in the thin films. High piezoelectric responses were obtained in the thin films, with values of approximately 75 and 83 pm V−1 in the (0 0 1) and (1 1 1)-oriented thin films, respectively. It is notable that remarkable piezoelectric properties were obtained in the (1 1 1)-oriented thin films. The (1 1 1)-oriented thin films have the potential to be used as multi-bit memory because of the reduction of degradation in ferroelectricity and various directional piezoelectricity. We compared the functionalities of the (0 0 1)- and (1 1 1)-oriented thin films and obtained different performances in the thin films. [ABSTRACT FROM AUTHOR]

Fetal bovine serum (FBS) has usually been used as a component of the medium for the culture of embryonic stem (ES) cells. However, FBS contains undefined factors, which promote cell proliferation and occasionally stimulate differentiation of ES cells. To establish an effective culture system for the derivation and maintenance of cat ES cells, we compared the effects of KnockoutTM Serum Replacement (Invitrogen, Seoul, South Korea)-supplemented medium (KSR-medium) and FBS-supplemented medium (FBS-medium) on the attachment and formation of primary ES-like cell colonies of isolated inner cell mass (ICM) derived from in vivo-produced blastocysts on mitotically inactivated cat embryonic fibroblast (CEF) feeders. An inseminated domestic female cat underwent ovariohysterectomy at Day 7 post-insemination, after which blastocysts were flushed from the uterine horns. Inner cell mass (ICM) was mechanically isolated from the in vivo-matured blastocysts (n = 22) and cultured in KSR-medium or FBS-medium on a CEF feeder layer at 39C, 5% CO2 in air. KSR-medium or FBS-medium consisted of knockoutTM DMEM supplemented with 20% KSR or FBS, 100 IU mL-1 penicillin/streptomycin, 2 mM l-glutamine, 1 MEM non-essential amino acids, 100 M -mercaptoethanol, and 1000 IU mL-1 recombinant mouse LIF. The results indicate that incidence of primary ICM attachment (91.6 14.4 vs. 55.5 9.6% in KSR- and FBS-medium, respectively; P < 0.05) and ES-like cell colony formation (63.8 12.7 vs. 27.7 4.8% in KSR- and FBS-medium, respectively; P < 0.05) is significantly affected by the ES cell culture medium. However, cat ES-like cells in KSR-medium did not actively proliferate in the primary culture. The number of cat ES-like cells in a colony after 5 days of culture was significantly higher in FBS-medium than in KSR-medium (749 82 vs. 383 55% in FBS- and KSR-medium, respectively; P < 0.05). A total of 10 ES-like cell colonies were formed in KSR-medium (n = 7) and FBS-medium (n = 3), and these expressed high levels of alkaline phosphatase activity (AP). Immunostaining analysis was positive for the ES cell-markers, Oct-4 and SSEA-3. To our knowledge, this is the first reported isolation of cat ES-like cells on CEF feeders in the absence of serum. A culture system of embryo-derived stem cells using serum-free medium may make it possible to directly examine the effects of factors added to culture medium on isolation and maintenance of cat ES cell lines in vitro.This work was supported by KOSEF (grant # M105250100 01-05N2501-00110). [ABSTRACT FROM AUTHOR]

Abstract  Effects of zinc [0 and 5.0 mg Zn kg−1 (soil)] on photosynthetic rate (PN), and chlorophyll fluorescence in leaves of maize (Zea mays L.) cv. Zhongdan 9409 seedlings grown under different soil moisture regimes (40–45 % and 70–75 % of soil saturated water content) were studied. Zn application did not enhance maize plant adaptation to drought stress. The relative water content and the water potential of leaves were not affected by Zn treatment. Moreover, The PN of drought-stressed plants was not improved by Zn supply. The increases of plant biomass, stomatal conductance and quantum yield of photosystem 2 due to Zn addition were notable in well-watered plants. [ABSTRACT FROM AUTHOR]

A high-performance liquid chromatography method was developed for the determination of related substances in an intravenous emulsion loaded with a paclitaxel-cholesterol complex. The separation was achieved using Agilent Eclipse XDB-C18 column (150 x 4.6 mm, 3.5 µm), which was kept at 40°. The gradient mobile phase consisted of acetonitrile and water with a low rate of 1.2 ml/min. The ultraviolet detection wavelength was set at 227 nm. The preparation of the sample solution began with the addition of anhydrous sodium sulphate to break the emulsion. Then, methanol and ethyl ether were added to pick up the drug and remove the accessories of the emulsion by extraction and centrifugation. Finally, paclitaxel was enriched by a nitrogen blow method and resolved with a mixture of methanol:glacial acetic acid (200:1). The method was proven to be selective, sensitive, robust, linear, repeatable, accurate and suitable for the determination of paclitaxel-related substances in the emulsion formulations, and the major degradation products in the potential pharmaceutical product were 7-epipaclitaxel and 10-deacetylpaclitaxel. [ABSTRACT FROM AUTHOR]

Background and Aim: Gastric cancers present with distinctive carcinogenesis pathways that vary with the mucin phenotypes. We attempted to elucidate the relations between the characteristics of the mucin phenotypes of gastric cancer and the tumor invasiveness. Methods: Gastric adenocarcinomas that were resected surgically between August 2005 and April 2007 were included in the present study. The gastric cancers were subclassified into gastric and intestinal mucin phenotypes if more than 10% of cancer cells exhibited gastric (MUC5AC and/or MUC6) and intestinal (MUC2 or CD10) markers, respectively. Results: The mucin phenotypes of 123 gastric cancers were gastric ( n = 31), intestinal ( n = 43), mixed ( n = 28) and unclassified ( n = 21). The mucin phenotype was related to histological type ( P < 0.001), Lauren's classification ( P = 0.001) and size ( P = 0.014) of the gastric adenocarcinoma, but not to its location or to the presence of Helicobacter pylori infection. The unclassified mucin phenotype exhibited the largest number of lymph node metastases ( P = 0.007), lymphatic invasions ( P < 0.001) and neural invasions ( P = 0.026), whereas the intestinal mucin phenotype exhibited the lowest invasiveness. Conclusion: The mucin phenotype reflects the biological behavior of gastric cancer, with the intestinal and unclassified mucin phenotypes exhibiting the lowest and highest invasiveness, respectively. [ABSTRACT FROM AUTHOR]

Abstract  Four new chamigrane sesquiterpenoids, (6S,10S)-10-bromo-3,11,11-trimethyl-7-methylidenespiro[5.5]undec-2-ene-4-one, (4S,6S,10S)-10-bromo-3,11,11-trimethyl-7-methylidenespiro[5.5]undec-2-ene-4-ol, (3R,4S,6S,10R)-10-bromo-3,11,11-trimethyl-7-methylidenespiro[5.5]undecane-3,4-diol, and (6S,7S,11R)-2-chloro-3,7,11-trimethyl-10-methylidenespiro[5.5]undec-2-ene-7-ol, were isolated from the sea hare Aplysia dactylomela. The chemical structures of new compounds were established by NMR spectroscopy and mass spectrometry. The cytotoxic activity of some of the obtained compounds against promyelocytic HL-60 and monocytic THP-1 leukemia cells was demonstrated. [ABSTRACT FROM AUTHOR]

Background/Aims: Vascular endothelial growth factor C (VEGF-C) and vascular endothelial growth factor D (VEGF-D) are potent lymphangiogenic and angiogenetic mediators in many kinds of tumors. However, the exact impacts of VEGF-C and VEGF-D on the prognosis of colorectal cancer (CRC) remain elusive. The aims of this study were to demonstrate the expression of VEGF-C and VEGF-D and to correlate their expression levels with clinicopathological factors and long-term survival in patients with CRC. Patients and Methods: Between January 1996 and January 1998, 69 patients with pathologically confirmed CRC who received routine follow-up at the Ruijin Hospital were included in this study. VEGF-C and VEGF-D protein expression and microvessel density of 69 surgical specimens were assessed by immunohistochemistry, with 20 samples of normal colorectal tissues as controls. All patients were followed up for 108 months or until death. The Immunohistochemical stains were quantified and analyzed by means of a Zeiss Axioplan 2 imaging analysis system. Results: The protein expression of VEGF-C and VEGF-D in tumor tissues was much higher than that in normal colorectal tissues (p < 0.01). The VEGF-C expression significantly correlated with lymph node metastasis (p = 0.011) and clinical stages of CRC (p < 0.01). The VEGF-D expression correlated with patient ages (p = 0.013), depth of tumor invasion (p = 0.013), and lymph node metastasis (p = 0.028). The expression of VEGF-C and VEGF-D was significantly correlated with the microvessel density. Both overall survival and disease-free survival at 108 months were significantly lower in the CRC patients with a high VEGF-C and/or a high VEGF-D expression, and the patients with a high expression of both VEGF-C and VEGF-D had the shortest overall survival and disease-free survival when compared with other patients. Conclusion: The VEGF-C or VEGF-D expression was significantly correlated with lymph node metastasis and long-term prognosis and could be applied as prognostic markers in CRC. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The development and application of second generation high temperature superconducting (2G-HTS) tapes have attracted much attention in China recently. Progress in upscaling high performance 2G-HTS tape production at Shanghai Superconductor Technology (SST) is reported in this paper. With ion beam assisted deposition, biaxially textured buffer layers with a configuration of CeO2/LaMnO3/MgO/Y2O3/Al2O3/C-276 have successfully been fabricated. In-plane and out-of-plane texture degrees of CeO2 films achieve 2°–4° and 2°, respectively. A multi-plume multi-turn pulsed laser deposition (PLD) system combined with the so-called ‘radiation assisted conductive heater’ has been proposed and further developed for REBCO layer deposition. Our effort was focused on minimizing the temperature variations in the deposition region by modifying the heating shield that assists the conductive heater of the drum-like cylinder. A tape travelling speed of 100–180 m h−1 can be achieved with a steady temperature profile when passing through the deposition zone, which is very beneficial for the growth of the REBCO layer. Taking advantage of the liquid phase growth mode, several compositions of superconducting films with a thickness in the range of 1–2.5 μm have been grown with high growth rates of over 40 nm s−1. Furthermore, the microstructures and superconducting performance were investigated in detail. Based on these studies, superconducting tapes with piece lengths of up to 500 meters have been developed. High Ic values at 77 K, self-field (over 520 A cm−1 width) or at low temperature, high magnetic field conditions (over 560 A/4 mm width at 4.2 K, 10 T, perpendicular field) have been achieved. Lamination and jointing techniques have also been developed by SST for power and magnet applications. [ABSTRACT FROM AUTHOR]

InAsSb nanowires (NWs) with a high Sb content have potential in the fabrication of advanced silicon-based optoelectronics such as infrared photondetectors/emitters and highly sensitive phototransistors, as well as in the generation of renewable electricity. However, producing optically efficient InAsSb NWs with a high Sb content remains a challenge, and optical emission is limited to 4.0 μm due to the quality of the nanowires. Here, we report, for the first time, the success of high-quality and optically efficient InAsSb NWs enabling silicon-based optoelectronics operating in entirely mid-wavelength infrared. Pure zinc-blende InAsSb NWs were realized with efficient photoluminescence emission. We obtained room-temperature photoluminescence emission in InAs NWs and successfully extended the emission wavelength in InAsSb NWs to 5.1 μm. The realization of this optically efficient InAsSb NW material paves the way to realizing next-generation devices, combining advances in III-V semiconductors and silicon. [ABSTRACT FROM AUTHOR]

The present study was carried out to investigate the effect of different ovary transport temperatures on in vitro development and post-thaw survivability of bovine embryos. Bovine ovaries were collected at a local slaughterhouse and transported at 4 different temperature categories to the laboratory: 7–10C (T1), 11–17C (T2), 18–25C (T3), and above 26C (control group). The cumulus–oocyte complexes (COCs) were aspirated from 2–8 mm antral follicles using a syringe with an 18 gauge needle. Selected COCs were washed in HEPES-buffered tissue culture medium (TCM-199) supplemented with 5% FBS. Sets of 50 COCs were matured for 22 h in 4-well dishes of TCM-199 supplemented with 5% FBS, 10 g mL-1 LH, and 10 g mL-1 FSH, that had been previously covered with mineral oil and equilibrated in an atmosphere of 5% CO2 in air at 39C. Mature COCs were fertilized with frozen–thawed semen treated with BO medium. To evaluate nuclear maturation to the metaphase II stage, the matured COCs were fixed in 1 : 3 acetic acid–ethanol for 30 s and stained with 3% basic Fuchsin. For embryo freezing, Day 7 and 8 blastocysts were equilibrated for 15 min in 1.8 M ethylene glycol as a cryoprotectant. Embryos were loaded into 0.25-mL straws at room temperature, plunged directly into a cooling chamber, kept at -7C for 10 min, including time for seeding, and further cooled to -35C at -0.3C min-1; after 2 min at this temperature, they were plunged into liquid nitrogen. Thawing was performed by keeping straws at room temperature for 10 s, followed by immersion in a water bath at 37C. The appearance of the embryos was evaluated immediately after warming and again at 24-h intervals for at least 3 days. The development rate was assessed by the re-expansion of the blastocoel and the hatching of blastocysts. Results were compared by ANOVA. The rates of maturation (to metaphase II), cleavage, and development to blastocysts were compared among treatment groups. Furthermore, frozen–thawed blastocysts were in vitro cultured to compare the survivability among groups. The maturation rates in the T1, T2, and T3 groups (24/40, 60.0%; 25/41, 61.0%; and 30/44, 68.2%, respectively) were significantly lower than that in the control group (36/44, 81.8%; P < 0.05). The cleavage rates in the T1 and T2 groups (61/116, 52.6% and 66/121, 54.5%) were significantly lower than that in the control group (112/134, 83.6%; P < 0.05). However, there was no difference in the development rate to blastocysts among all groups (27.9–33.0%; P > 0.05). The survivability of frozen–thawed embryos was significantly lower in the T1 group (6/13, 46.2%) than in the T2 (11/16, 68.8), T3 (13/18, 72.2%), and control groups (19/26, 73.1%; P < 0.05). In conclusion, the results suggest that ovary transport at 26C may be optimal for better in vitro development and survival of frozen–thawed embryos produced in vitro. Furthermore, exposure of ovaries to temperatures below 10C during transport may significantly decrease both in vitro development and survivability of frozen-thawed blastocysts. [ABSTRACT FROM AUTHOR]

We present a new measurement of the α-spectroscopic factor (Sα) and the asymptotic normalization coefficient for the 6.356 MeV 1/2+ subthreshold state of 17O through the 13C(11B, 7Li)17O transfer reaction and we determine the α-width of this state. This is believed to have a strong effect on the rate of the 13C(α, n)16O reaction, the main neutron source for slow neutron captures (the s-process) in asymptotic giant branch (AGB) stars. Based on the new width we derive the astrophysical S-factor and the stellar rate of the 13C(α, n)16O reaction. At a temperature of 100 MK, our rate is roughly two times larger than that by Caughlan & Fowler and two times smaller than that recommended by the NACRE compilation. We use the new rate and different rates available in the literature as input in simulations of AGB stars to study their influence on the abundances of selected s-process elements and isotopic ratios. There are no changes in the final results using the different rates for the 13C(α, n)16O reaction when the 13C burns completely in radiative conditions. When the 13C burns in convective conditions, as in stars of initial mass lower than ∼2 M☼ and in post-AGB stars, some changes are to be expected, e.g., of up to 25% for Pb in our models. These variations will have to be carefully analyzed when more accurate stellar mixing models and more precise observational constraints are available. [ABSTRACT FROM AUTHOR]