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Using improved voxel tomography method for energetic neutral atom (ENA) emission, global 3‐D distributions of O+ and H+ ions in the inner magnetosphere are reconstructed from ENA images remotely sensed by the Two Wide‐angle Imaging Neutral‐atom Spectrometers (TWINS) mission during 15 July 2012 magnetic storm. The compositions of ENA‐O and ‐H are separated by statistical fitting based on start‐pulse‐height distributions. The errors in iterative inversions range from 0.12 to 0.28 at 16 and 32 keV. The reconstructed ion flux intensities at different storm phases match well with independent satellite in situ measurements. It is found that: (a) Responding to a pulse jump of solar wind dynamic pressure along with a northward reversal of IMF Bz during the initial phase, H+ ion fluxes enhanced greatly on outer dipole L‐shell of 6.5–8.0 in pre‐midnight off equator. Ts‐05 model tracing and pitch angles distribution of line‐of‐sights for ENA imaging suggest these be likely attributed to nearly field‐aligned earthward plasma flow from plasma‐sheet boundary layer region. Meanwhile, the trapped ring current (RC) ion fluxes peak at L ∼ 5 in the pre‐midnight equatorial region, decreasing with increasing latitude. (b) During the storm maximum the equatorial O+ fluxes have two separated peaks. The main one appeared in dusk at L ∼ 4, while the minor one in the pre‐dawn appeared at very low L ∼ 2.75 where the flux ratio O+/(O++H+) reached 60%. (c) The O+ flux fractions over equator exhibit prominent dusk‐dawn asymmetry, reversing from dusk quadrant prevailing before the main phase to dawn ascendant during the storm maximum. Key Points: The first study to perform O+ inversions from energetic neutral atom images and global 3‐D distributions are acquired by voxel tomography methodEquatorial O+ fluxes during storm maximum have separate peaks at dusk and dawn, with ascendant fraction of O+/(O++H+) at dawn quadrantSpecified meridian fluxes show dual components, relating severally to trapped ring current and plasma transport from/to magnetotail [ABSTRACT FROM AUTHOR]

Crack inspection is a crucial but labor-intensive work of maintenance for in-service bridges. Recently, the development of fully convolutional network (FCN) provides pixel-wise semantic segmentation, which is promising as a means of automatic crack detection. However, the demand for numerous training images with pixel-wise labels poses challenges. In this study, a benchmark data set called a bridge crack library (BCL) containing 11,000 pixel-wise labeled images with 256×256 resolution was established, which has 5,769 nonsteel crack images, 2,036 steel crack images, 3,195 noise images, and their labels. It is aimed at crack detection on multiple structural materials including masonry, concrete, and steel. The raw images were collected by multiple cameras from more than 50 in-service bridges during a period of 2 years. Various crack images with numerous crack forms and noise motifs in different scenarios were collected. Quality control measures were carried out during the raw image collection, subimage cropping, and subimage annotation steps. The established BCL was used to train three deep neural networks (DNNs) for applicability validation. The results indicate that the BCL could be applied to effectively train DNNs for crack detection and serve as a benchmark data set for performance evaluation of DNN models. [ABSTRACT FROM AUTHOR]

Nodular iron brake discs often fail due to serious thermal fatigue cracking. The existence of graphite complicates the repair of the crack defects of ductile iron. This study presented a new idea of ductile iron brake disc remanufacturing based on coupled bionics and repaired ductile iron with thermal fatigue cracks discontinuously by bio-inspired crack blocked units fabricated by laser remelting with different laser parameters. Then tensile strength and thermal fatigue crack resistance of the units with various laser energy inputs were tested. The hardness, microstructure and phases in the units were characterized, as well as the anti-crack mechanism of the units being analysed. It was found the units positively impacted both the thermal fatigue resistance and tensile strength. The unit fabricated with a laser energy of 463 68 15 . +19 -15 + J/mm² exhibited the highest tensile strength and the most significant improvement on thermal fatigue properties, which increased by 20.65 and 250% respectively compared with the untreated sample. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The poor prognosis of advanced laryngocarcinoma was associated with the epithelial-mesenchymal transformation (EMT), which was related to the dysregulated expression of free fatty acids receptor 4 (FFAR4). By detecting the expression of FFAR4 in laryngocarcinoma and its relation with the clinicopathological characteristics and prognosis of laryngocarcinoma, as well as conducting in vitro experiments, our aim is to explore the role of FFAR4 in laryngocarcinoma biological and clinical process. PATIENTS AND METHODS: The protein expression level of FFAR4 in 54 cases of laryngocarcinoma and 30 cases of laryngocarcinoma adjacent tissues was detected by immunohistochemistry. Combined with clinical follow-up data, the Kaplan-Meier survival curve and log-rank test were conducted to compare the relation between the expression of FFAR4, the clinicopathological characteristics, and the 5-year survival rate in laryngocarcinoma. Multivariable Cox regression analysis revealed the independent predictors for the prognosis of laryngocarcinoma. CCK-8 and migration assay were used to test cell proliferation and migration abilities. RESULTS: FFAR4 was upregulated in laryngocarcinoma tissues and influenced cell proliferation and migration abilities. The FFAR4 expression was related to the age and lymph node metastasis in laryngocarcinoma patients and indicated a reduced 5-year survival rate and increased lymph node metastasis. CONCLUSIONS: The upregulation FFAR4 expression was associated with the lymph node metastasis and the prognosis. FFAR4 can significantly promote laryngocarcinoma cell proliferation and migration in vitro. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To explore the role of KCNMA1-AS1 in epithelial ovarian cancer (EOC) and its underlying mechanism. PATIENTS AND METHODS: We first screened out the differentially expressed lncRNAs (KCNMA1-AS1) in the GEO (gene expression omnibus) database. The relationship between KCNMA1-AS1 expression and prognosis of EOC with different pathological types was analyzed by meta-analysis. Subsequently, KCNMA1-AS1 expressions in EOC tissues and normal ovarian tissues were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between KCNMA1-AS1 level with progression-free survival (PFS) and overall survival (OS) of EOC was analyzed. Furthermore, proliferation and migration of EOC cells transfected with the corresponding plasmids were analyzed by Cell Counting Kit-8 (CCK-8) and transwell assay, respectively. Apoptosis-related genes in EOC cells were detected by Western blot. RESULTS: KCNMA1-AS1 was a risk factor for prognosis in high-grade, advanced and serous EOC. Upregulated KCNMA1-AS1 was found in EOC tissues than that of normal tissues, showing the diagnostic potential of KCNMA1-AS1 in EOC. Statistical analysis indicated that KCNMA1-AS1 was not correlated with the DFS, OS, age, histological type, lymph node metastasis and recurrence, but related to FIGO stage of EOC patients. For in vitro experiments, the proliferation and migration of were enhanced, and apoptosis of HO8910 cells overexpressing KCNMA1-AS1 was inhibited. Furthermore, elevated expressions of Caspase-3 and Caspase-9, as well as reduced expression of Bcl-xL, were observed after KCNMA1-AS1 knockdown in EOC cells. CONCLUSIONS: KCNMA1-AS1 is overexpressed in EOC and negatively correlated with its prognosis. KCNMA1-AS1 participates in the occurrence and development of EOC by promoting proliferation, migration and inhibiting apoptosis of ovarian cancer cells via apoptosis pathway. [ABSTRACT FROM AUTHOR]

The effects of three typical refractory elements (rhenium, chromium and zirconium) substituting the molybdenum atom in Co7Mo6 μ phase were investigated using first-principles calculations based on the density functional theory (DFT). Energy (including binding energy and defect energy) and electronic structures (including density of states and charge density) of Co7Mo5X (X=rhenium, chromium and zirconium) were calculated. The optimized lattice structure of Co7Mo6 agrees well with the experimental data. The calculated results show the bonding between doped rhenium atom and its nearest neighbor molybdenum and cobalt atoms gets visibly stronger, contributing to the good stability of the unit cell. Neverthless, the bonding between chromium and its nearest neighbor molybdenum and cobalt is weaker, and the zirconium-molybdenum and zirconium-cobalt bonds are much weaker. The results reveal rhenium tends to participate in the formation of μ phase, but zirconium and chromium atoms are not prone to concentrate in μ phase. [ABSTRACT FROM AUTHOR]

By using the accelerometer measurements from CHAMP and GRACE satellites, the tidal signatures of the thermospheric mass density and zonal wind at midlatitudes have been analyzed in this study. The results show that the mass density and zonal wind at southern midlatitudes are dominated by a longitudinal wave-1 pattern. The most prominent tidal components in mass density and zonal wind are the diurnal tides D0 and DW2 and the semidiurnal tides SW1 and SW3. This is consistent with the tidal signatures in the F region electron density at midlatitudes as reported by Xiong and Lühr (2014). These same tidal components are observed both in the thermospheric and ionospheric quantities, supporting a mechanism that the non-migrating tides in the upper atmosphere are excited in situ by ion-neutral interactions at midlatitudes, consistent with the modeling results of Jones Jr. et al. (2013).We regard the thermospheric dynamics as the main driver for the electron density tidal structures. An example is the in-phase variation of D0 between electron density and mass density in both hemispheres. Further research including coupled atmospheric models is probably needed for explaining the similarities and differences between thermospheric and ionospheric tidal signals at midlatitudes. [ABSTRACT FROM AUTHOR]

Hollow tin oxide (SnO2) nanobelts have been synthesized through a facile single capillary electrospinning method, and characterized by XRD, Raman, SEM, TEM and BET analysis. SnO2 hollow nanobelts exhibit excellent sensing performances to acetone at 260 °C. The response is up to 6.7 when the sensor is exposed to 5 ppm acetone. The response and recovery times are about 38 and 9 s, respectively. The sensor can detect acetone down to 5 ppm and up to 50,000 ppm. These results demonstrate that SnO2 hollow nanobelts can be used as the sensing material for fabricating high performance acetone sensors. The formation mechanism of the hollow nanobelts is also discussed, which is attributed to solvent evaporation rate, phase separation and collapse. [ABSTRACT FROM AUTHOR]

In this work, porous SnO2 hollow nanofibers were fabricated by electrospinning technique and calcination procedure. The hollow SnO2 nanofibers were characterized by means of X-ray diffraction, energy dispersive X-ray detector, scanning electron microscopy, transmission electron microscopy, Brunauer-Emmet-Teller and the gas sensing properties for ethanol were also investigated. The results indicated that rough porous SnO2 hollow nanostructure with large specific surface area (26.43m²/g) was composed of very small nanoparticles (about 20nm). The pore size was calculated above 4nm. Furthermore, the gas sensor based on this hollow structure has an optimum operating temperature of 300°C, high sensitivity, quick response and good selectivity for ethanol. [ABSTRACT FROM AUTHOR]

The controls of merging electrical field Em IMF (interplanetary magnetic field) magnitude B on the storm-time changes in upper thermospheric mass density are statistically investigated using GRACE accelerometer observations the OMNI data of solar wind IMF for great storms during2002 -2006 . It reveals the following: (1 ) The correlation coefficients between the air mass density changes the parameters of Em B are generally larger at lower latitudes than at higher latitudes larger in noon midnight sectors than in dawn dusk. ( 2) The most likely delay time (MLDT) of mass density changes in respect to Em is about 1 . 5 h ( 4. 5 h) at high (low) latitudes having no distinct local time dependence while it is h at middle latitudes in all the local time sectors except for noon which is longer than at low latitudes. A similar fact of longer delay time at mid-latitude is also seen for B. The MLDTs for B at various latitudes are all local time dependent distinctly with shorter delay time in noon/midnight sector larger in dawn/dusk. Despite of widely spread of the delay time IMF B exhibits still larger correlation coefficients with mass density changes among the interplanetary parameters. (3 ) The linear control factor of B on the density changes increases for large B in contrast to somewhat saturation trend for larger Em. (4) The influence of B Em on the mass densities shows different behavior for different types of storms. The influence intensity of Em is much stronger for CIR-driven than for CME-driven storm while it is not so distinct for B. On the local time asymmetry of the influence both Em B have largest influence at noon sector for CME-driven storms while an obviously larger intensification of the influence is found in dawn/dusk sector during CIR storms especially for parameter Em. [ABSTRACT FROM AUTHOR]

In this paper, we present further observational evidence for the transpolar propagation of large-scale traveling ionospheric disturbances (LSTIDs) from their nightside source region to the dayside reported by Cai et al. (2011). Slant total electron content (STEC) observed by longitudinally aligned GPS receiver chains in North American and European sectors was analyzed to demonstrate presences of LSTIDs at both nightside and dayside mid-latitude. Signatures of TID were inferred from phase difference in time series of STEC perturbations (TECP) derived from measurements of ground-based GPS receivers, which are separated by hundreds of kilometers longitudinally. Periods of the daytime and nighttime ionospheric disturbances were estimated to be around 128 min, being in good agreement with that of the transpolar AGW (atmospheric gravity wave) recorded by EISCAT (European Incoherent Scatter Scientific Association)/ ESR (EISCAT Svalbard Radar) radars. On the dayside, the LSTID moved equatorward with an average phase speed of ∼440ms-1. In North American sector, however, southward speed of the nighttime LSTID was much slower, being around 160ms-1. We suggest that the observed daytime and nighttime mid-latitude LSTIDs are likely to have the same source region, being located somewhere at nighttime auroral latitude. Having been launched on the nightside, the waves propagate simultaneously equatorward and poleward. The equatorward-moving waves are recorded by GPS receiver chain in North American sector. The polewardmoving waves, however, cross the polar cap from nightside to dayside and then are detected consecutively at high and midlatitudes by EISCAT/ESR radars and GPS receiver chains, respectively. [ABSTRACT FROM AUTHOR]

In this paper, we present observational evidence for the trans-polar propagation of large-scale Traveling Ionospheric Disturbances (TIDs) from their nightside source region to the dayside. On 13 February 2001, the 32m dish of EISCAT Svalbard Radar (ESR) was directing toward the geomagnetic pole at low elevation (30°) during the interval 06:00-12:00UT (MLT≈UT + 3 h), providing an excellent opportunity to monitor the ionosphere F-region over the polar cap. The TIDs were first detected by the ESR over the dayside north polar cap, propagating equatorward, and were subsequently seen by the mainland UHF radar at auroral latitudes around geomagnetic local noon. The propagation properties of the observed ionization waves suggest the presence of a moderately large-scale TIDs, propagating across the northern polar cap from the night-time auroral source during substorm conditions. Our results agree with the theoretical simulations by Balthazor and Moffett (1999) in which poleward-propagating large-scale traveling atmospheric disturbances were found to be self-consistently driven by enhancements in auroral heating. [ABSTRACT FROM AUTHOR]

Orbit-averaged mass density measurements derived from the satellites CHAMP and GRACE are used to investigate the storm-time prediction model developed by Liu et al. (2010) at different altitudes. This model uses as input only the solar wind merging electric field. From 2002 to 2005 in total 31 major geomagnetic storms with minimum Dst< -100 nT are selected for a statistical study. The results show that the model can successfully predict the storm-time mass density changes at both CHAMP and GRACE altitudes. The orbit-averaged density of CHAMP and GRACE show very similar distribution in shape, regardless of the orbital local time difference, but the amplitude of GRACE density is about 30% of that of CHAMP density. An optimal delay time of 4.5 h has been found for both CHAMP and GRACE densities. During the four years the scale factor a between merging electric field and mass density for CHAMP altitude remains basically at the same level, a =0.5, while the a for GRACE density shows a declining trend, and its value is only 30% of that for CHAMP density. The storms driven by corotating interaction regions (CIR) have in general larger a values than the storms driven by coronal mass ejections (CMEs). [ABSTRACT FROM AUTHOR]

Based on the multi-year data base (2001-2009) of CHAMP Planar Langmuir Probe (PLP) data and GRACE K-Band Ranging (KBR1B) data, typical features of ionospheric plasma irregularities are studied at the altitudes of CHAMP (300-400 km) and GRACE (∼500 km). The phenomena we are focusing on are the equatorial plasma bubbles (EPBs). Similar seasonal/longitudinal (S/L) distributions of EPB have been found at both CHAMP and GRACE altitudes during solar active and quiet years. Peak EPB occurrence rates, defined as number of events within an S/L bin divided by the number of passes over that bin, decrease from the high and moderate solar flux period (2001-2005) to the low solar flux period (2005-2009) from 80% to 60% and 60% to 40% at CHAMP and GRACE altitudes, respectively. On average the occurrence rate increases linearly with solar flux at about the same rate at CHAMP and GRACE. For high flux levels (P10.7>200) non-linear increases are observed at GRACE. The occurrence rate increases rapidly after 19:00 local time (LT) during high solar flux periods. Around solar minimum rates increase more gently and peak around 22:00 LT. The highest occurrence rates are encountered at latitudes around 10° north and south of the dip equator. Results from the two altitudes support the notion that EPBs form regions of depleted plasma along geomagnetic fluxtubes. It is shown for the first time that in regions of high occurrence rates EPBs are associated with fluxtubes reaching greater apex heights than those in regions of low rates. [ABSTRACT FROM AUTHOR]

With the help of four years (2002-2005) of CHAMP accelerometer data we have investigated the dependence of low and mid latitude thermospheric density on the merging electric field, Em, during major magnetic storms. Altogether 30 intensive storm events (Dstmin <-100 nT) are chosen for a statistical study. In order to achieve a good correlation Em is preconditioned. Contrary to general opinion, Em has to be applied without saturation effect in order to obtain good results for magnetic storms of all activity levels. The memory effect of the thermosphere is accounted for by a weighted integration of Em over the past 3 h. In addition, a lag time of the mass density response to solar wind input of 0 to 4.5 h depending on latitude and local time is considered. A linear model using the preconditioned Ēm as main controlling parameter for predicting mass density changes during magnetic storms is developed: ρ =0.5Ēm+ρamb, where ρamb is based on the mean density during the quiet day before the storm. We show that this simple relation predicts all storm-induced mass density variations at CHAMP altitude fairly well especially if orbital averages are considered. [ABSTRACT FROM AUTHOR]

The energy and nucleus-independent chemical shift (NICS) of 95 isomers of N-confused porphyrazine (NCPz), including normal porphyrazine (N0CPz), N-confused porphyrazine (N1CPz), doubly N-confused porphyrazine (N2CPz), triply N-confused porphyrazine (N3CPz), and fully N-confused porphyrazine (N4CPz), have been calculated by the density-functional theory (DFT) method. The stability of NCPz decreased by increasing the number of confused pyrrole rings and the macrocycle tend to be destabilized stepwise by approximately +21 kcal/mol. The relative energies of the most stable isomers in confusion level are 0 kcal/mol (N0CPz-1), +23.481 (N1CPz-5), +41.849 (N2CPz-a4), +61.738 (N3CPz-b3), and +84.596 (N4CPz-b13), respectively. The most stable isomers of N2CPz, N3CPz, and N4CPz are not necessarily the most aromatic but rather nonaromatic, especially in the case of N3CPz and N4CPz. On the other hand, the magnitude of the aromaticity estimated by NICS for these isomers does not differ largely. The NICS values of the most aromatic isomers are -15.5411 (N0CPz-1), -14.0458 (N1CPz-2), -12.8171 (N2CPz-d1), -11.5961 (N3CPz-b6), and -12.8012 ppm (N4CPz-a6), respectively. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [ABSTRACT FROM AUTHOR]

Similar to the Dst index, the SYM-H index may also serve as an indicator of magnetic storm intensity, but having distinct advantage of higher time-resolution. In this study the NARX neural network has been used for the first time to predict SYM-H index from solar wind (SW) and IMF parameters. In total 73 time intervals of great storm events with IMF/SW data available from ACE satellite during 1998 to 2006 are used to establish the ANN model. Out of them, 67 are used to train the network and the other 6 samples for test. Additionally, the NARX prediction model is also validated using IMF/SW data from WIND satellite for 7 great storms during 1995-1997 and 2005, as well as for the July 2000 Bastille day storm and November 2001 superstorm using Geotail and OMNI data at 1AU, respectively. Five interplanetary parameters of IMF Bz, By and total B components along with proton density and velocity of solar wind are used as the original external inputs of the neural network to predict the SYM-H index about one hour ahead. For the 6 test storms registered by ACE including two super-storms of min. SYM-H<-200 nT, the correlation coefficient between observed and NARX network predicted SYM-H is 0.95 as a whole, even as high as 0.95 and 0.98 with average relative variance of 13.2% and 7.4%, respectively, for the two super-storms. The prediction for the 7 storms with WIND data is also satisfactory, showing averaged correlation coefficient about 0.91 and RMSE of 14.2 nT. The newly developed NARX model shows much better capability than Elman network for SYM-H prediction, which can partly be attributed to a key feedback to the input layer from the output neuron with a suitable length (about 120 min). This feedback means that nearly real information of the ring current status is effectively directed to take part in the prediction of SYM-H index by ANN. The proper history length of the output-feedback may mainly reflect on average the characteristic time of ring current decay which involves various decay mechanisms with ion lifetimes from tens of minutes to tens of hours. The Elman network makes feedback from hidden layer to input only one step, which is of 5 min for SYM-H index in this work and thus insufficient to catch the characteristic time length. [ABSTRACT FROM AUTHOR]

Dependence relation on a set is an important concept in universal algebra. In this paper, we prove the equivalence of three different kinds of dependence systems. [ABSTRACT FROM AUTHOR]

Objectives We have shown previously that ultrasound examination performed by one experienced operator can be useful to exclude homozygous α0-thalassemia in a tertiary referral center. This study aimed to determine whether the technique was still applicable when performed by several operators and in different centers. Methods At the Maternal and Neonatal Hospital of Guangzhou (MNH) and Tsan Yuk Hospital of Hong Kong (TYH), women at risk of homozygous α0-thalassemia were given the option of a non-invasive approach (using serial ultrasound examinations at 12-15, 16-20 and 25-30 weeks' gestation) to exclude an affected pregnancy. The fetal cardiothoracic ratio (CTR) was measured at each of these examinations and the placental thickness was measured at 12-15 weeks' gestation. The operators of MNH received training on the ultrasound examination techniques at TYH and the quality of the subsequent ultrasound examinations was checked regularly. The final diagnosis of homozygous α0-thalassemia was confirmed using an invasive test. Results Of 832 at-risk pregnancies studied in the two hospitals, 168 (20.2%) were affected. The overall sensitivity and specificity of the non-invasive approach was 100% and 95.6%, respectively. At MNH, the need for an invasive test was reduced by 80.8%, and all the affected pregnancies were diagnosed before 24 weeks' gestation. The results achieved at MNH were comparable with those at TYH. The at-risk pregnancies including the affected ones presented at a more advanced gestational age at MNH. At each hospital, one affected pregnancy was missed at the 12-week scan but this was subsequently detected at the 15-18-week scan. Conclusions This non-invasive approach to exclude homozygous α0-thalassemia can be applicable when it is performed by several operators and in different centers. [ABSTRACT FROM AUTHOR]

Reactivation of varicella-zoster virus (VZV) is one of the commonest complications after stem cell transplantation, and often presents with atypical manifestations. We describe two unusual cases of occult disseminated zoster in allogeneic stem cell transplant recipients, presenting as severe abdominal pain and syndrome of inappropriate antidiuretic hormone secretion/hyponatraemia, and accompanied by leukaemia relapse. There was complete clinical recovery with high-dose aciclovir and intravenous immunoglobulin. Prompt treatment of leukaemia relapse also resulted in complete remission. A possible immunological link between concurrent breakdown of immune control of VZV and leukaemia is discussed. [ABSTRACT FROM AUTHOR]

Ge-containing silicon oxide (GSO) films (5-15 nm) and Si-rich silicon oxide (SSO) films (5-15 nm) were deposited using the RF magnetron sputtering technique with a Ge-SiO[sub 2] and a Si-SiO[sub 2] composite target, respectively. The Au/GSO/p-Si and Au/SSO/p-Si structures were fabricated and their electroluminescence (EL) characteristics were comparatively studied. Both of the Au/GSO/p-Si and Au/SSO/p-Si structures have rectifying behavior. All the EL spectra from the two types of the structure have almost unchanged peak positions around 650 nm (∼ 1.9 eV) and are independent of applied forward biases. The EL mechanisms for the Au/GSO/p-Si and Au/SSO/p-Si structures have been discussed. [ABSTRACT FROM AUTHOR]

Polarized Raman spectroscopy has been performed to investigate the effects of the electric field on 0.67PbMg1/3Nb2/3O3–0.33PbTiO3 (PMN–33%PT) single crystal. The electric-field-evolution of Raman spectra differed from one microarea to another. In the crossed polarization geometry, the abrupt changes in the intensities of the Raman bands at around 570 and 780 cm-1 indicated the occurrence of the field induced phase transition from the MC-type to the MA-type monoclinic structure. On the other hand, the Raman spectra for the microarea that was initially in the MA phase exhibited no obvious changes. All these results revealed the microheterogeneity in PMN–33%PT single crystal, which is useful for understanding the field-induced superior electromechanical properties. [ABSTRACT FROM AUTHOR]

Rehmannia glutinosa (Gaertn.) Libosch. ex Fisch. & Mey. was very tolerant to paraquat (1,1'-dimethyl-4,4'-bipyridinium). The paraquat concentration required to reduce dry weight of R. glutinosa by 50% (GR50) was 24 mM, whereas a similar effect was obtained with 0.75 mm in Zea mays L. (maize, cv. Dekalb) and Glycine max (L.) Merr. (soybean, cv. Kwangkyo). When 1.5 mM paraquat in 10% aqueous extract of R. glutinosa was applied to maize and soybean, growth inhibition reached 24% and 7%, respectively, of the untreated control. Decreased activity of paraquat due to the extract also occurred in both leaf discs and chloroplasts of soybean. The total amount of [14C]paraquat absorbed into soybean leaves after 48 h was 34%, but it was reduced to 17% when the extract was added. Translocation of [14C]paraquat was also inhibited in the presence of the extract. In thin-layer chromatography (TLC) analysis using various solvent systems, Rf values of [14C]paraquat with the extract differed from those without the extract. The results suggested that the aqueous extract of R. glutinosa contained a substance which could nullify paraquat activity. [ABSTRACT FROM AUTHOR]