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The Chinese pond turtle (Mcturemysreevesii) is one of the most important commercial and medicinal chelonians in China. In this study, 87Chinese pond turtle individuals were collected to represent five captive populations of this species in China. Twelve polymorphic microsatellite markers were used to evaluate the genetic diversity of five cultured populations, and it revealed that the level of genetic diversity was relatively high in these cultured populations. Except for Mclw03, Mclw06 and Mmul in the GZ population, all microsatellite loci of the other four populations did not deviated from Hardv-Weinberg equilibrium. The analysis of molecular variance (AMOVA) revealed that 80.7% of the genetic variation within populations and 19.3% among populations. Pair wise FST further showed that there was moderate to high degree of genetic differentiation between populations. Phylogenetic analysis separated the Chinese pond turtle samples in the present study into two clusters, with the first group included Guangzhou, Nanning and Haikou populations and the second group consist of individuals from two populations from Wuhu. Our results demonstrated that different degrees of inbreeding existed in five captive populations and it is urgent to raise a new superior breeding population with high genetic diversity using turtles from different captive populations. [ABSTRACT FROM AUTHOR]

The solid solution crystals, Bi4(GexS1-x)3O12 (BGSO) with x = 0, 0.05, and 0.15, have been grown by the modified vertical Bridgman method. The as-grown crystals show 80% of transmittance with an absorption edge of 285 nm. The relative light yields of BGSO crystals are found to be 7.2%, 6.3%, and 4.2% of CsI(Tl) crystal for x = 0, 0.05, and 0.15, respectively. The energy resolutions of these crystals are 18.9%, 21.3%, and 24.7%, respectively, with PMT for 662 keV gamma rays at room temperature when exposed to 137Cs-ray. The scintillation performance of BGSO crystals clearly deteriorates with the increase of Ge content. However, the appropriate number of germanium ions doped to BSO crystal can improve its crystallization behavior and effectively restrain component segregation. It is expected that large size crystals of BGSO will be grown and applied to the dual readout calorimeter in the nearest future. [ABSTRACT FROM AUTHOR]

We have designed a power stabilizer based on a round-trip erbium-doped fiber amplifier (EDFA) structure to suppress the low-frequency relative intensity noise (RIN) for a narrow linewidth fiber laser. The noise suppressor is analyzed theoretically and its feasibility is verified experimentally. For a short-cavity single-frequency fiber laser with this device, about 20 dB low-frequency RIN improvement is achieved (down to -120 dB Hz-1 at 10 Hz). The corresponding frequency noise is also reduced by a factor of 1.6. The proposed method is an effective solution to achieve a low-frequency low RIN laser source for highly coherent detection applications. [ABSTRACT FROM AUTHOR]

Diffuse optical imaging (DOI) for detecting and locating targets in a highly scattering turbid medium is treated as a blind source separation (BSS) problem. Three matrix decomposition methods, independent component analysis (ICA), principal component analysis (PCA), and nonnegative matrix factorization (NMF) were used to study the DOI problem. The efficacy of resulting approaches was evaluated and compared using simulated and experimental data. Samples used in the experiments included Intralipid-10% or Intralipid-20% suspension in water as the medium with absorptive or scattering targets embedded. [ABSTRACT FROM AUTHOR]

Abstract  Aerobic granules efficient at degrading methyl tert-butyl ether (MTBE) were successfully developed in a well-mixed sequencing batch reactor (SBR). Treatment efficiency of MTBE in the reactor during the stable operations exceeded 99.8%, and effluent MTBE was consistently below 800 μg/L. The specific MTBE degradation rate was observed to increase with increasing MTBE initial concentrations from 25 to 400 mg/L, peaked at 18.2 mg-MTBE/g-VSS h, and declined with further increases in MTBE concentration as substrate inhibition effects became significant. There was a good fit between these biodegradation data and the Haldane equation (R 2 = 0.976). Microbial community DNA profiling was carried out using denaturing gradient gel electrophoresis (DGGE) of polymerase chain reaction amplified 16S rDNA. The aerobic granule was found to contain a wide diversity of microorganisms. More than 70% similarity among the samples in the time period examined indicated a highly stable microbial community as the reactor reached the stable operation. [ABSTRACT FROM AUTHOR]

Pulsed corona discharge carried out in the gas phase has been shown to be a low cost solution for wastewater treatment. In this study, the results show that the nitrogen dissociated during corona discharge in the gas phase formed nitric acid in solution, which resulted in a drop in solution pH. The phenol removal could be described in accordance with a first-order reaction in a basic buffer solution, but not in initial neutral and basic non-buffered solutions. This indicates that basic conditions facilitate phenol removal, whilst the formation of nitric acid in solution resulted in decrease in the phenol removal rate. This study also shows that most of the oxidants used for phenol removal came mainly from the dissociation of water molecules at the surface of the liquid phase and / or the gas phase very close to the liquid surface in discharging conditions, not from the gas dissociation in the bulk gas phase, and therefore, it is more effective to keep the solution basic than to change the component of gas in the reactor when removing phenol from water using corona discharge. [ABSTRACT FROM AUTHOR]

Electrophoretic analysis of six types of tissue (serum, erythrocyte, liver, kidney, muscle and eye) and seven different isoenzymes (LDHJ, MDH, Est, ADHI IDH, α-GPDH and SOD) from both healthy grass carp, Cienopharyngodon idellus Ctwicr & Valenciennes, and carp affected by haemorrhagic disease was performed. It was found that: (1) Enzymes from diseased grass carp showed the most drastic changes within each tissue. The absolute activity of LDH in serum from the diseased fish increased to approximately twice that of the healthy fish; whereas the relative activity of A4 and A3B1, the main components of A sub-base in both serum and erythrocytes. was accelerated. (2) The isoenzymic changes in the control groups, diseased fish, artificially infected fish and healthy fish from diseased ponds indicated that biochemical changes occurred in the tissues before pathological change. [ABSTRACT FROM AUTHOR]

Multiple martensitic transformation peaks were observed from differential scanning calorimetry curves in aged Mn50Ni25Ga25 alloys in which transformation temperature varied with aging temperature. The magnetization and coercivity were enhanced as a result of aging above magnetic transition temperature. A maximum magnetization up to 54 emu/g and a magnetization difference between two phases of 28 emu/g was achieved in the alloy aged at 873 K. However, coercivity as large as 1.2 kOe was obtained in 573 K aged alloy, with a high saturation field, which can be understood in terms of domain wall pinning. [ABSTRACT FROM AUTHOR]

Ferromagnetic metal/oxide heterostructures with tunable perpendicular magnetic anisotropy (PMA) and large tunnel magnetoresistance (TMR) are building blocks of spintronic devices. With unprecedented high performance, the perpendicularly magnetized CoFeB/MgO system has been extensively investigated. Here, we report that Mo/FeNiB/MgO and its inverted structure MgO/FeNiB/Mo show large interfacial PMA with high thermal stability, it ensures spontaneous perpendicular magnetization with effective PMA field of about 5 kOe in Mo/FeNiB(1.2 nm)/MgO and MgO/FeNiB(1.5 nm)/Mo after annealing at 400 °C, comparable to the CoFeB/MgO system. Remarkably, the coercivity of perpendicularly magnetized FeNiB layers in either continuous film or patterned structure of micrometers is smaller than that of the CoFeB counterpart by an order. We have fabricated perpendicular magnetic tunnel junctions with pseudo-spin valve structure Mo/FeNiB/MgO/CoFeB/Mo, which show TMR of 113% at room temperature and 221% at 5K. These results suggest that Mo/FeNiB/MgO heterostructure can be an important PMA material candidate in exploiting next-generation spintronic devices. [ABSTRACT FROM AUTHOR]

Discrete dislocation dynamics (DDD) simulations are being increasingly employed to investigate metal plasticity at the mesoscale. However, in spite of its ability to access beyond the length and time limits of atomistic methods, the DDD model is still limited by its high computational cost, with ranges of achievable strains too low and strain rates too high by several orders of magnitude compared with typical experimental conditions. By combining the efficiency of the recently developed subcycling time-integrator with the highly parallel architecture of graphics processing unit (GPU) devices, we developed a DDD model that provides significant acceleration compared to existing implementations. Our GPU-accelerated implementation enables large-scale DDD simulations that can reach relevant levels of strain using a moderate amount of computational resources. [ABSTRACT FROM AUTHOR]

Three-dimensional discrete dislocation dynamics methods (3D-DDD) have been developed to explicitly track the motion of individual dislocations under applied stress. At present, these methods are limited to plastic strains of about one percent or less due to high computational cost associated with the interactions between large numbers of dislocations. This limitation motivates the construction of minimalistic approaches to efficiently simulate the motion of dislocations for higher strains and longer time scales. In the present study, we propose geometrically projected discrete dislocation dynamics (GP-DDD), a method in which dislocation loops are modeled as geometrical objects that maintain their shape with a constant number of degrees of freedom as they expand. We present an example where rectangles composed of two screw and two edge dislocation segments are used for modeling gliding dislocation loops. We use this model to simulate single slip loading of copper and compare the results with detailed 3D-DDD simulations. We discuss the regimes in which GP-DDD is able to adequately capture the variation of the flow stress with strain rate in the single slip loading condition. A simulation using GP-DDD requires ∼40 times fewer degrees of freedom for a copper single slip loading case, thus reducing computational time and complexity. [ABSTRACT FROM AUTHOR]

3D fluoroscopic images represent volumetric patient anatomy during treatment with high spatial and temporal resolution. 3D fluoroscopic images estimated using motion models built using 4DCT images, taken days or weeks prior to treatment, do not reliably represent patient anatomy during treatment. In this study we developed and performed initial evaluation of techniques to develop patient-specific motion models from 4D cone-beam CT (4DCBCT) images, taken immediately before treatment, and used these models to estimate 3D fluoroscopic images based on 2D kV projections captured during treatment. We evaluate the accuracy of 3D fluoroscopic images by comparison to ground truth digital and physical phantom images. The performance of 4DCBCT-based and 4DCT-based motion models are compared in simulated clinical situations representing tumor baseline shift or initial patient positioning errors. The results of this study demonstrate the ability for 4DCBCT imaging to generate motion models that can account for changes that cannot be accounted for with 4DCT-based motion models. When simulating tumor baseline shift and patient positioning errors of up to 5 mm, the average tumor localization error and the 95th percentile error in six datasets were 1.20 and 2.2 mm, respectively, for 4DCBCT-based motion models. 4DCT-based motion models applied to the same six datasets resulted in average tumor localization error and the 95th percentile error of 4.18 and 5.4 mm, respectively. Analysis of voxel-wise intensity differences was also conducted for all experiments. In summary, this study demonstrates the feasibility of 4DCBCT-based 3D fluoroscopic image generation in digital and physical phantoms and shows the potential advantage of 4DCBCT-based 3D fluoroscopic image estimation when there are changes in anatomy between the time of 4DCT imaging and the time of treatment delivery. [ABSTRACT FROM AUTHOR]

Bottom pinned IrMn/[Co/Pt] multilayer films with relatively thin Pt layers ([?]10 ) grown on a Ta/Pt buffer have been found to exhibit favourable perpendicular exchange bias (PEB) and well-defined perpendicular anisotropy at room temperature. However, even the optimum film suffers from the same problem as those reported previously, i.e. the exchange bias field is just slightly larger than the coercivity. By replacing the Co layer in contact with IrMn by a 6-8 Co60Fe40 layer, the exchange bias is drastically enhanced while the large perpendicular anisotropy is sustained and the coercivity changes little. The exchange bias field for the IrMn/CoFe/[Pt/Co] films with sufficient high perpendicular anisotropy can reach a value as high as 950 Oe, which is almost three times the coercivity, and the corresponding unidirectional anisotropy, 0.22 erg cm[?]2, considerably exceeds the best result at room temperature for various PEB systems ever reported. The present result suggests that PEB strongly depends on the composition of the ferromagnetic layer across the interface, which opens an effective avenue to boost PEB. [ABSTRACT FROM AUTHOR]