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The aim of this study was to explore the effects of 6-week aerobic exercise alone, resveratrol alone, and combined aerobic exercise and resveratrol intervention on a non-alcoholic fatty liver rat model. In order to explore an ideal way to improve the effect of treating NAFLD, and to provide a certain theoretical basis for the future outcome of NAFLD and the setting of exercise prescriptions. To this aim thirty male Sprague Dawley rats were randomly divided into 5 groups: Control, NAFLD, N + E, N + R, N + E + R. NAFLD model was established by feeding high-fat diet for 16 weeks. After successful modeling, the exercise group used treadmill exercise for 6 weeks of aerobic exercise intervention, and the resveratrol group was gavaged for 6 weeks (dose: 40 mg/kg). After the experiment, it was marked by group number. The blood indicators of the rats were measured: TG, TC, FFA, GLU, LDL-c, HDL-c, ALT, AST, adiponectin, leptin. Take the liver tissue and divide it into five parts, each wrapped in tin foil and put into liquid nitrogen to be tested for TNF-α and IL-6 according to the group mark. After successful modeling, compared with the control group, the levels of TG, TC, FFA, LDL-c, ALT, AST and GLU in NAFLD group were increased (P < 0.01, P < 0.01, P < 0.01, P < 0.01, P < 0.01, P < 0.01, P < 0.05), the level of HDL-c decreased (P < 0.05); TNF-α and IL-6 increased significantly (P < 0.01), and adiponectin decreased significantly (P < 0.01). After 6 weeks of different interventions, compared with NAFLD group, TG, FFA, ALT, AST and GLU of intervention group decreased significantly, HDL-c increased (P < 0.05), while the level of TC in N + R group and the level of LDL-c in N + E group also decreased but there was no significant change. Moreover, compared with NAFLD group, leptin (P < 0.01, P < 0.01, P < 0.05), TNF-α (P < 0.05, P < 0.05, P < 0.01) and IL-6 (P < 0.01, P < 0.05, P < 0.01) of intervention group were all significantly decreased, and adiponectin was significantly increased (P < 0.01). Either aerobic exercise or resveratrol alone have different improvement on glucose, lipid metabolism disorders and adipocytokine disorders in NAFLD rats. But the improvements are greatest with combined aerobic exercise and resveratrol intervention. It has a certain promotion effect on the outcome of NAFLD rats. [ABSTRACT FROM AUTHOR]

Hf-doped In 2 O 3 transparent conductive polycrystalline films (IHFO) were grown at a low substrate temperature by radio frequency magnetron sputtering for the applications of silicon-based solar cell. The effect of argon flow rate on the electrical and optical properties of the films was investigated. Low temperature thermal treatment improved IHFO films properties, with the optimal Hall mobility of 79.6 cm 2 /Vs and resistivity of 3.76 × 10 −4 Ω cm. The average transmittance of the 807 nm thick IHFO films in the range of 300–1500 nm was above 83%. The carrier density was utilized to evaluate the plasma wavelength of IHFO conducting film which was 1.8 μm. The optimized IHFO film was then applied to amorphous silicon germanium thin film solar cells as the contacting layer. Compared to the cell without such a layer, the efficiency was higher by 0.35%. [ABSTRACT FROM AUTHOR]

The morphous silicon germanium (a-SiGe) thin films are fabricated in a radio frequency plasma enhanced chemical vapor deposition system. This paper summarizes our recent works on how to make a suitable a-SiGe solar cell to enhance the light absorption in the long wavelength region. Up to now, a single junction p-i-n a-SiGe solar cell with an initial efficiency of 9.06% is obtained. The long wavelength response in QE is broadened to 950 nm. The QE reaches about 26.63% at 800 nm wavelength. [ABSTRACT FROM AUTHOR]

For mobile radars installed on a gyro-stabilised platform (GSP) that can steadily follow an East-North-Up (ENU) frame, attitude biases (ABs) of the platform and offset biases (OBs) of the radar are linear dependent variables. Therefore ABs and OBs are unobservable in the linearized registration equations; however, when combining them as new variables, the system becomes observable, and this model has been called the unified registration model (URM). Unlike GSP mobile radars, un-stabilised GSP (or UGSP) mobile radars are installed on the platform directly and rotate with the platform simultaneously. For UGSP, it is testified that both types of biases are independent and observable because the time-varying attitude angles (AAs)1 of the platform are included in the registration equations, which destroy the dependencies of both kinds of biases and lead us to propose a completely different linearized registration model– the All Augmented Model (AAM). AAM employs all OBs and ABs in the state vector and a Kalman filter (KF) to produce their estimates. Numerical simulation results show that the estimated performance of AAM is close to the Cramér-Rao lower bound (CRLB) and that the Root Mean Square Errors (RMSEs) of the rectified measurements by using AAM are more than 500 m smaller than by URM in all directions. [ABSTRACT FROM PUBLISHER]

Abstract: The performances of p–i–n amorphous silicon germanium (a-SiGe:H) solar cell modules were investigated post annealing at different temperatures. When the annealing temperature is 190°C, the best performance of solar cell modules is obtained. The efficiency of solar cell modules is improved from 5.11% to 7.91%. The enhancement in quantum efficiency spectra at long wavelength post annealing may be attributable to there being significantly less absorption in intrinsic layer. The microstructural properties of the a-SiGe:H thin films are investigated post annealing at different temperatures. The results show that the low temperature annealing process leads to the improvement in the film microstructure. [Copyright &y& Elsevier]

In the sense of minimum concentration ellipse, the optimal deployment of multiple passive sensors in bearing-only location system is studied in terms of cut angle. It is found that the optimum cut angle depends only on l, the ratio of the distance between target and the baseline of the two sensors to the baseline length. When l is greater than 0.5, the optimum cut angle can be obtained if the deployment of the target and the two passive sensors is an isosceles triangle with the baseline length as its base side. When l is less than 0.5, the optimum cut angle can be obtained if the target and the two passive sensors are located on the circle with the baseline length as its diameter, that is, the deployment of the target and the two passive sensors being a right triangle. When l equals 0.5, the optimum cut angle can be obtained if the target and the two passive sensors are deployed on an isosceles right triangle. The global minimum value of concentration ellipse can be asymptotically reached by decreasing the ratio l to zero based on these properties of the optimum cut angle. [ABSTRACT FROM AUTHOR]

Abstract: Relationships between plant diversity (H diversity index) and above-ground biomass (as a surrogate of productivity) were analysed using quadrat data and biomass measures from a precipitation gradient in length of ca. 1000km in temperate grasslands, south-eastern Mongolia. These analyses were performed both at different ecological scales including taxonomic or functional levels, such as species, community and ecosystem, and at different geographic scales, such as local, landscape and region. Results showed that diversity–productivity relationships differ with different observed ecological and geographical scales in the temperate grasslands of south-eastern Mongolia. In detail, at the individual species level, all relationships between plant diversity and above-ground biomass from local scale to landscape and regional scales are positive and non-linear. At the community level, such relationships are mostly unimodal from landscape to regional scales. At the ecosystem level, the relationship is unimodal at regional scale. A general trend of diversity–productivity relationships in this region seems to be from positive non-linear to unimodal patterns if the scales change from low to high ecological levels and from small to large geographical scales. The unimodal pattern is common in this region. [Copyright &y& Elsevier]

Using remote sensing technique, we investigated real-time Nostoc sphaeroides Kütz (Cyanobacterium) in Closed System under microgravity by SHENZHOU-2 spacecraft in January 2001. The experiments had 1g centrifuges in space for control and ground control group experiments were also carried out in the same equipments and under the same controlled condition. The data about the population growth of Nostoc sp. of experiments and temperature changes of system were got from spacecraft every minute. From the data, we can find that population growth of Nostoc sp. in microgravity group was higher than that of other groups in space or on ground, even though both the control 1g group in space and 1g group on ground indicated same increasing characteristics in experiments. The growth rate of 1.4g group (centrifuged group on ground) was also promoted during experiment. The temperature changes of systems are also affected by gravity and light. Some aspects about those differences were discussed. From the discussion of these results during experiment, it can be found that gravity is the major factor to lead to these changes. [Copyright &y& Elsevier]

Abstract: The flexible polymer solar modules are fabricated by glass substrate transfer technology. The deposition system of silicon thin film solar cell deposited directly on glass substrate is used to prepare flexible ones. In addition, the process of module cascade is compatible with one on the glass substrate. A conversion efficiency up to 5.38% of 100 cm2 flexible amorphous silicon thin film solar modules using a glass as temporary substrate during processing and a polymer as permanent substrate in the finished module was achieved. The flexible polymer solar modules have a good light stability. [Copyright &y& Elsevier]

The needle-like antireflection Hf-doped In 2 O 3 thin films (IHFO) were prepared at a substrate temperature of 200 °C by glancing angle radio frequency magnetron sputtering technology. The structural, electrical and optical properties of the needle-like IHFO thin films were characterized. The significant reduction of reflection loss of the conventional and needle-like IHFO bilayer films deposited on the textured silicon was observed. The short-circuit current and efficiency of the solar cell were improved by 0.52 mA/cm2 and 0.39% utilizing a needle-like IHFO thin film as an antireflection layer. • Antireflection Hf-doped In 2 O 3 (IHFO) thin films were prepared by glancing angle magnetron sputtering technology. • The structural, electrical and optical properties of the films were characterized. • The reduction of reflection loss of the conventional and needle-like IHFO double films was observed. • The short-circuit current and efficiency of the solar cell were improved by needle-like IHFO film. [ABSTRACT FROM AUTHOR]

Abstract: Different aluminum-doped ZnO (AZO)/metal composite films, including AZO/Al, AZO/Ag/Al and AZO/Ag/NiCr/Al, were utilized as the back reflectors for p-i-n hydrogenated amorphous silicon germanium (a-SiGe:H) thin film solar cells. It was found that AZO/Al had a better performance than single Al electrode and the thickness of AZO film could strongly affect the short-circuit current density (Jsc ) of the solar cells. However, AZO/Ag/Al, which was expected to improve the back reflectance further, gave out a bad effect, due to the inter diffusion of Ag and Al. While a nickel–chromium (NiCr) film was inserted between Ag and Al as a diffusion barrier, the highest Jsc was achieved. So AZO/Ag/NiCr/Al could be utilized as an improved AZO/metal back reflector for p-i-n a-SiGe:H solar cells. [Copyright &y& Elsevier]

Investigations of the structures of gold nanowires are performed by using genetic algorithm simulation based on the molecular dynamics with a glue potential. Results are reported for some local clusters and defect polyhedra in nanowires. The pair correlation functions and pair analysis technique are used to study the cluster in nanowires. Not only are Frank–Kasper polyhedra and Bernal hole polyhedra detected, but also a variety of defects in nanowires with big diameter. Nanowires with small diameter have a splitting of second peak in PCF and characteristic amorphous features are observed in nanowires with small diameter. The angular correlation functions of gold nanowire have also been studied. Both the favorable energy and the small distortion result in bond pairs having the appropriate population. A suitable proportion of the number of bond pairs is an important factor for the nanowire forming ability. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Highlights • The tortuosity fractal dimension is introduced to the model. • The diffusion coefficient of power-law fluids is derived. • The W-M function is applied to manifest the fractal characters of the pores. • The comparisons between the simulation and experiment show validity of the new model. Abstract The study of fluid diffusion is an important aspect of heat and mass transfer of the porous fibrous materials. This work established a fractal model for the diffusion of power-law fluids in porous fibrous materials by considering the pore size distribution and the tortuosity of the capillary. Adopting the Darcy's law and the Hagen–Poiseuille's law, the diffusion coefficient of power-law fluids is derived as a function of the tortuosity fractal dimension, the pore size fractal dimension and the flow behavior index, in which the phase transition and the adsorption effect of fiber as well as the influence of gas diffusion and temperature change are taken into consideration. And the Weierstrass–Mandelbrot (W-M) function is applied to manifest the detailed fractal characters of the pores. Focusing on an analytical expression of the diffusion of power-law fluids in porous fibrous materials, the changes of liquid volume fraction, gas concentration and temperature distribution subjected to the specification initial and boundary conditions are simulated numerically. The test of this approach on the height of fluids when the bottom of cotton fabrics is immersed in the water display the clear diffusion of fluid in fiber. Our preliminary results indicate the important roles that the porosity and flow behavior index play in the fluids transfer in the porous fibrous materials: the fluids with lower power law index rise higher heights and diffuse more rapidly, meanwhile, the height increases with the porosity. [ABSTRACT FROM AUTHOR]

Chromium nitride coatings exhibit good mechanical, corrosion and oxidation protection properties and can have various orientations. Preferred orientations of CrN(200) and Cr2N(111) were successfully deposited on SKD11 by unbalanced magnetron sputtering. To compare with different orientations, several mechanical properties of deposited films were studied, e.g. hardness, adhesion and wear behavior. The structural characterization and surface morphology were investigated using atomic force microscopy (AFM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The chemical composition and stoichiometry were determined using X-ray photoelectron spectroscopy (XPS). The cross-section morphology of CrN coating is a columnar structure and Cr2N is a denser structure. Of the two orientations CrN(200) and Cr2N(111), CrN(200) possesses stronger adhesion and lower hardness. [Copyright &y& Elsevier]

In this paper, we analyze the melting behavior of zirconium nanowire using the results of a series of molecular dynamics simulations. Our calculation employs a well-fitted, tight-binding many-body potential for zirconium atoms. The melting point of the nanowire is predicted by the root-mean-square displacements for inner and outer shells. Our simulations predict two melting behaviors: one is the inner melting and the other is the outer melting. Our results reveal that the melting of nanowire starts from the inner shell atoms. The melting point of zirconium nanowire is lower than the bulk value (2125 K). Moreover, the melting point of the inner shell is lower than that of the outer shell. A coexistence of crystal and liquid units is observed in the melting process of nanowire. An investigation of local clusters is carried out to further analyze the melting mechanism of the nanowire. The presence of the local clusters 1331, 1321, 1211, etc. is an indication of disordered structures. The pair and angular correlation functions are also presented for the analysis of the melting behavior. It is not only the diffusion of single atom but the diffusion of clusters result in the occurrence of the melting. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The method of cut blasting is widely used in tunnelling excavation, which concerns the success in subsequent stop blasting and smooth blasting. Rock masses in deep tunnels are subjected to high in-situ stress, and the mechanisms of damage evolution of rock mass in deep tunnels induced by cut blasting are not well studied. In this paper, a tension and compression-shear damage model is developed, and then is implemented into the commercial software LS-DYNA as a user-defined material model. To validate the newly developed model, the comparison between numerical results and an existing field test is conducted. The effects of free-surface boundary conditions, in-situ stress and the coefficient of lateral pressure on cut blasting are considered in depth. Numerical results indicate that the superstition of stress wave and the reflected tension waves from free surfaces contribute to the damage interconnection near cut holes. The high in-situ stress has the resistance on the radially oriented pressure and the damage extension around cut holes. The coefficients of lateral pressure influence the extending direction of the tensile damage zone. [ABSTRACT FROM AUTHOR]

The frequency of huge debris flows greatly increased in the epicenter area of the Wenchuan earthquake. Field investigation revealed that runoff during rainstorm played a major role in generating debris flows on the loose deposits, left by coseismic debris avalanches. However, the mechanisms of these runoff-generated debris flows are not well understood due to the complexity of the initiation processes. To better understand the initiation mechanisms, we simulated and monitored the initiation process in laboratory flume test, with the help of a 3D laser scanner. We found that run-off incision caused an accumulation of material down slope. This failed as shallow slides when saturated, transforming the process into debris in a second stage. After this initial phase, the debris flow volume increased rapidly by a chain of subsequent cascading processes starting with collapses of the side walls, damming and breaching, leading to a rapid widening of the erosion channel. In terms of erosion amount, the subsequent mechanisms were much more important than the initial one. The damming and breaching were found to be the main reasons for the huge magnitude of the debris flows in the post-earthquake area. It was also found that the tested material was susceptible to excess pore pressure and liquefaction in undrained triaxial, which may be a reason for the fluidization in the flume tests. [ABSTRACT FROM AUTHOR]

The knowledge of the association of polycyclic aromatic hydrocarbons (PAHs) with organic matter and carbonaceous materials is critical for a better understanding of their environmental transport, fate, and toxicological effects. Extensive studies have been done with regard to the relationship of PAHs with total organic carbon (TOC) and elemental carbon (EC) in different environmental matrices. The relationship between PAHs and the two subtypes of EC, char (combustion residues) and soot (produced via gas-to-particle conversion) also has been tested in field and laboratory experiments using reference materials. However, a direct comparison of associations of PAHs between with char and with soot in real environmental matrices has to our knowledge not yet been reported because of a lack of methodology to differentiate them. In this study, char and soot were measured using the IMPROVE method to test their associations with 12 EPA priority PAHs measured in topsoil samples ( N = 22, top 10 cm) collected from the Guanzhong Plain and in surface sediment samples ( N = 32, top 5 cm) from the Wei River (central China). In both soils and sediments, ∑12PAHs were more strongly associated with soot than with char, mainly due to the fact that soot and PAHs were produced in the same gas phase during combustion, had a strong affinity for each other, and were transported and deposited together, while char, the combustion residue, was transported differently to PAHs due to its large particle size. Stronger correlations between PAHs and the different carbon fractions (TOC, soot, and char) in sediments than in soils were observed, which is associated with the redistribution of PAHs among the organic matter pools in water because of the processes during soil erosion and sedimentation in the river. [ABSTRACT FROM AUTHOR]

Abstract: The concentrations of organic compounds, including n-alkanes and polycyclic aromatic hydrocarbons (PAHs), in fine particles (PM2.5) were measured in an urban area of Guangzhou before, during, and after the 16th Asian Games (9–30 November 2010). Higher average concentrations of n-alkanes and PAHs occurred in the nighttime, presumably due to a restriction on motor vehicle operation during the day and the accumulation of pollutants due to temperature inversions at night. The carbon preference index, contributions of wax n-alkanes, and PAHs diagnostic ratios indicated that the main sources of n-alkanes and PAHs were anthropogenic, especially motor vehicle emissions. The CMAQ model was used to estimate the percentages of biogenic organic aerosol in the total organic aerosol, then the ratios of source marker PAHs to biogenic organic carbon were used to evaluate the air pollution control policies effectiveness during the Asian Games. [Copyright &y& Elsevier]

Abstract: Daily concentrations of lead (Pb) were determined for PM2.5 samples collected from an urban location in Xi’an, China from 2007 to 2009 to assess the effects of the phasing out of leaded gasoline in 2000. The Pb concentrations (annual average: 0.306 μg m−3, range: below detection limit to 2.631 μg m−3) have declined after the phasing out of leaded gasoline, but the concentrations were still higher than those reported in many other cities. Seasonal variations of Pb were significant, with high concentrations in winter, presumably due to the burning of coal, and low concentrations in summer, due to a deep mixed layer and scavenging of aerosols by precipitation. Correlation analyses and enrichment factor calculations both indicated that anthropogenic sources had a large influence on atmospheric Pb. The lead isotope ratios were low in winter (the average 207Pb/206Pb ratio was 0.843 ± 0.032; 208Pb/206Pb was 1.908 ± 0.058) and high in summer (207Pb/206Pb was 0.860 ± 0.032; 208Pb/206Pb was 2.039 ± 0.057), suggesting that coal combustion was the major Pb source in winter and vehicular emission was the major Pb source in summer. Positive Matrix Factorization receptor model indicated that there were five major sources for Pb in PM2.5. Coal combustion was the major contributor, accounting for 39.0% PM2.5 mass, followed by vehicular emissions (30.4%). Other contributors included 17.8% from industrial emissions, 11.6% from biomass burning, and 1.2% from fugitive dust. [ABSTRACT FROM AUTHOR]

Abstract: Daily PM2.5 and water-soluble inorganic ions (Na+, NH4 +, K+, Mg2+, Ca2+, Cl−, NO3 − and SO4 2−) were collected in Xi''an (34.23°N, 108.88°E), China from March 2006 to March 2007. PM2.5 was collected using battery-powered mini-volume samplers. And the ions were determined by ion chromatography from the measured aerosol mass. The annual average mass concentration of PM2.5 was found to be 194.1±78.6μgm−3, which exceeded substantially the international guidelines for health concerns. The seasonal average mass concentration of PM2.5 was highest in winter (266.8μgm−3) and lowest in summer (138.6μgm−3). The three highest abundant ions were SO4 2−, NO3 −, and NH4 +, with average concentrations of 35.6±19.5μgm−3, 16.4±10.1μgm−3, and 11.4±6.8μgm−3, which were accounted for 18.7%, 8.0%, and 5.7% of the PM2.5 mass, respectively. The major ions were in the species of (NH4)2SO4, NH4HSO4 and NH4NO3, and their concentrations were highest in winter, due to high coal combustion. The concentrations of Ca2+ were higher in spring than other seasons, due to the higher mineral dust concentrations. Ca2+ was strongly correlated with CO3 2−, which was calculated as the difference in the measured cations minus anions. Ion balance calculations indicate that the PM2.5 was acidic, and this result is consistent with the measurement of pH values. Sulfur oxidation ratio was higher in summer and autumn, which implies that the formation of secondary sulfate-rich particles is favored by warm and relatively moist weather. Nitrogen oxidation ratio was highest in autumn. [Copyright &y& Elsevier]

Abstract: A comprehensive study of the morphology and luminescence characteristics of nonpolar m-plane GaN etched in hot acids was presented. It was found that many four-sided pyramidal pits were distributed on the etched GaN surface with the long side perpendicular to the [112̄0] direction, corresponding to the threading dislocations. When compared to the as-grown GaN, DAP emission intensity and its LO-phonon coupling phenomenon in the etched GaN were greatly attenuated, whereas the intensity of BSF-related band almost kept constant due to its immunity to chemical etching. Especially, a new PSF-related emission at 3.32eV emerged in CL spectra of etched GaN. Simultaneously, partial relaxation of compressive stress happened for the etched GaN epilayer according to the red shift of NBE emission in photoluminescence (PL) and E 2(high) phonon peak in the Raman spectra. Contrary, the DAP peak in etched GaN was blueshifted, likely due to the reduced impurity level fluctuation by etching. In addition, the different behaviors were discussed for NBE and defect-related transitions in the etched GaN, characterized by excitation power- and temperature-dependent PL. [ABSTRACT FROM AUTHOR]

Abstract: Free-standing graphene sheets have been imaged by scanning transmission electron microscopy (STEM). We show that the discrete numbers of graphene layers enable an accurate calibration of STEM intensity to be performed over an extended thickness and with single atomic layer sensitivity. We have applied this calibration to carbon nanoparticles with complex structures. This leads to the direct and accurate measurement of the electron mean free path. Here, we demonstrate potentials using graphene sheets as a novel mass standard in STEM-based mass spectrometry. [Copyright &y& Elsevier]

Abstract: The crystalline, surface, and optical properties of the (101¯3¯) semipolar GaN directly grown on m-plane sapphire substrates by hydride vapor phase epitaxy (HVPE) were investigated. It was found that the increase of V/III ratio led to high quality (101¯3¯) oriented GaN epilayers with a morphology that may have been produced by step-flow growth and with minor evidence of anisotropic crystalline structure. After etching in the mixed acids, the inclined pyramids dominated the GaN surface with a density of 2×105 cm−2, revealing the N-polarity characteristic. In the low-temperature PL spectra, weak BSF-related emission at 3.44eV could be observed as a shoulder of donor-bound exciton lines for the epilayer at high V/III ratio, which was indicative of obvious reduction of BSFs density. In comparison with other defect related emissions, a different quenching behavior was found for the 3.29eV emission, characterized by the temperature-dependent PL measurement. [Copyright &y& Elsevier]

Abstract: The combination of somatic cell nuclear transfer (SCNT) and transgenic technology leads to the production of transgenic cloned animals, wherein the preparation of competent transgenic donor cells is the pivotal upstream step. The purpose of this study was to establish an efficient procedure to prepare human lactoferrin (hLTF) transgenic donor cells for SCNT. Thus, two cell culture systems were employed: caprine mammary epithelial cells (for evaluation of the hTLF transgenic expression in vitro), and fetal-derived fibroblast cells (for identification of competent transgenic donor cells). Induced by hormonal signals, recombinant hLTF was detected in the supernatant of transfected mammary epithelial cells by Western blot. Reliable hLTF transgenic fibroblast cell clones were identified by screening with multiple PCR amplification, EGFP fluorescence, and chromosomal counting (32.5±2.3%). This study may provide an effective upstream system to prepare SCNT donor cells for the production of human recombinant pharmaceuticals from the milk of transgenic animals. [Copyright &y& Elsevier]

Abstract: The objective was to investigate the effect of phytohemagglutinin (PHA) on the fusion of mammary gland epithelial (MGE) cells into enucleated oocytes in goats. The toxicity of PHA was evaluated by testing its effect on the development of parthenogenetic caprine oocytes. The effective dose and duration of PHA treatment (100μg/mL, 20min incubation) was selected and used to compare fusion efficiency and embryo development following nuclear transfer. Two electrofusion protocols, chamber fusion (CF) and pressurized microelectrode fusion (pMEF), were also compared, when couplets were treated with and without PHA (100μg/mL, 20min). Fusion rate of couplets increased from 52.8 to 74.0% for the CF protocol (P <0.05), but was not significantly different for the pMEF protocol (72.7% vs. 78.1%) after PHA treatment. There were no significant differences between treated group and control in rates of subsequent cleavage or blastocyst development. Following transfer of the cloned blastocysts derived from the PHA-treated group and the control group into synchronized recipients, pregnancy rates (Day 30) were not significantly different between treated group and control (28.6% vs. 25.0%). However, all recipients aborted within 120d, microsatellite DNA analyses confirmed that the aborted fetuses were genetically identical to the donor goat. In conclusion, the fusion rate of caprine MGE cell couplets was improved by pre-incubating couplets in medium containing 100μg/mL PHA prior to electrical pulsing, and embryos derived from PHA treatment established early pregnancies. [Copyright &y& Elsevier]

Abstract: A family of stable single- and double-ring-like Ga n As n (3⩽ n ⩽14) clusters is given. The structures and properties of them are investigated using the density-functional theory with generalized gradient approximation. The transition of Ga n As n structural evolution from two- to three-dimension occurs at about the atom number 7. Single-ring is not stable when the cluster size n is larger than 6. Double-rings are energetically more favorable than single-rings. All double-ring Ga n As n clusters with n have high symmetry of D(n/2)d . The transition region of average binding energy and on-site charge is Ga6As6(b) and Ga8As8. The bonding characteristic of these rings is covalent. These clusters are all semiconductor-like. [Copyright &y& Elsevier]

Abstract: The studies on the structure and electronic properties of Al13OH clusters are carried out using a density functional theory with generalized gradient approximation. C1(I) and Ih ontop forms are the ground-state structures for neutral and anionic Al13OH, respectively; and the hollow form is not stable. The structure of Al13 moieties dramatically changes for Al13OH due to the charge transfer from Al13 cluster to OH. While the Al13 moieties can keep their structures because of the extra electron localized on the moiety in Al13OH− clusters. The binding strength of OH to Al13 − and Al13 are similar in many cases. Population analysis shows that the bonding characteristic of these clusters is mainly ionic. For Al13OH− clusters, the ontop forms are more stable than the bridge forms. The large binding energy and HOMO–LUMO gap imply that neutral clusters would be physically and chemically stable. [Copyright &y& Elsevier]

Abstract: We report electrical transport measurements on individual disordered multiwalled carbon nanotubes, grown catalytically in a nanoporous anodic aluminum oxide template. In both as-grown and annealed types of nanotubes, the low-field conductance shows an dependence on temperature , suggesting that hopping conduction is the dominant transport mechanism, albeit with different disorder-related coefficients . The electric field dependence of low-temperature conductance behaves as at high electric field at sufficiently low . Finally, both annealed and unannealed nanotubes exhibit weak positive magnetoresistance at . Comparison with theory indicates that our data are best explained by Coulomb-gap variable-range hopping conduction and permits the extraction of disorder-dependent localization length and dielectric constant. [Copyright &y& Elsevier]

Abstract: The ground state structures of clusters are obtained by a genetic algorithm with a Gupta-like many-body potential, and further optimized using the density functional theory. The structure of pure atomic clusters Co38 and Pt38 is truncated octahedron. For the clusters with , 2 and 34–37, their structures are slightly distorted configuration of Co38 and Pt38. The structures of all the other bimetallic clusters are defective pattern based on icosahedrons. Segregation effect can be seen in the ground structures of bimetallic clusters. The Pt atom prefers to locate on the surfaces of these clusters. The cluster with , 5, 23, 29, 33, they are relatively more stable than their neighbors. The magnetic moment of Co38 is in agreement with experiment. The nonzero moment of Pt38 cluster is found. Compared with Co38, the introduction of Pt atom dramatically reduces the total magnetic moments of clusters. [Copyright &y& Elsevier]

Abstract: The ground state structures of Co/Cu and Co/Pt clusters are obtained by empirical genetic algorithm, and further optimized using the density functional theory with generalized gradient approximation. For Co13, Pt13 and Cu13, they show perfect I h symmetry. The structures of bimetallic clusters are slightly distorted configuration of Co13. The average magnetic moment of Co13 is 2.38 μ B /atom, and that of Cu13 and Pt13 is nonzero. The local moments of the central atom are smaller than that of the surface ones for Co13 and Cu13. But the cases are not held for Pt13. The total magnetic moment of clusters Co/Pt monotonously decreases with increasing the concentration of Pt atoms. But the things are much more complicated for clusters Co/Cu, and the reasons are discussed in detail. [Copyright &y& Elsevier]

Abstract: In this Letter, a tight-binding many body potential is used to simulate the melting process. A splitting second peak is first observed in the pair correlation function which implies supercooled feature. The splitting second peak is the consequence of the disordered local atomic structures. The curves of internal energy, root mean square bond length and the local clusters are used to monitor the phase transition. We show that upon heating the nanowire undergoes a coexistence of liquid and crystalline units. [Copyright &y& Elsevier]

Epitaxial growth of Zn-doped InGaAs on InP substrates has been carried out at 550°C by LP-MOCVD. Hole concentration as high as 6×1019 cm−3 has been achieved at the H2 flow rate of 20 sccm through DEZn bubbler. The lattice constant of Zn-doped InGaAs was found to be dependent on the flow rate of DEZn, and the tensile strain mismatch increases with increasing H2 flow rate of DEZn. The negative lattice mismatch of heavily Zn-dopped InGaAs may be due to the small covalent bonding radius of zinc and the combination of butane from ethyl of DEZn and TEGa. And the latter accelerates the pyrolysis of TEGa, which is the dominant mechanism in determining the negative mismatch of Zn-doped InGaAs. [Copyright &y& Elsevier]

Effects of V/III ratio on heavily Si doped InGaAs and InP were studied using low pressure metalorganic chemical vapor deposition (LP-MOCVD) at a growth temperature of 550°C. In InGaAs, as the V/III ratio decreases from 256 to 64, the carrier concentration increases from 3.0×1018 to 5.8×1018 cm−3; and the lattice mismatch of InGaAs to InP was observed to vary from −5.70×10−4 to 1.49×10−3. In InP, when the V/III ratio decreases from 230 to 92, the same trend as that in Si doped InGaAs was observed that the carrier concentration increases from 9.2×1018 to 1.3×1019 cm−3. The change of AsH3 was found to have stronger effect on Si incorporation in InGaAs at lower growth temperature than at higher growth temperature. [Copyright &y& Elsevier]

The thermodynamic behavior of near ground-state isomers of Au55 clusters are investigated through molecular-dynamic simulations using an n-body effective potential. During relaxation at certain energies, non-reversible structural transitions (from cuboctahedron to icosahedron, and then to disordered configuration) occur well below the melting temperature. We show in this Letter on a picosecond scale the motion of the individual atoms in a cluster during these transformations, demonstrating that the processes involved are either collective distortions of the entire cluster or migration of individual or small groups of atoms. In both cases the cohesive energies of the system go smoothly without any significant barrier during transitions. [Copyright &y& Elsevier]

Irrigated rice (Oryza sativa L.) yield increases in Asia have slowed down in recent years. Further, yield increases are likely to occur in smaller increments through fine-tuning of crop management. On-farm experiments at 179 sites in eight key irrigated rice domains of Asia were conducted from 1997 to 1999 to evaluate a new approach for site-specific nutrient management (SSNM). Large variation in initial soil fertility characteristics and indigenous supply of N, P, and K was observed among the eight intensive rice domains as well as among farms within each domain. Field- and season-specific NPK applications were calculated by accounting for the indigenous nutrient supply, yield targets, and nutrient demand as a function of the interactions between N, P, and K. Nitrogen applications were fine-tuned based on season-specific rules and field-specific monitoring of crop N status. The performance of SSNM was tested for four successive rice crops. Average grain yield in the SSNM increased by 0.36 Mg ha−1 (7%) compared to the current farmers’ fertilizer practice (FFP) measured in the same cropping seasons or 0.54 Mg ha−1 (11%) compared to the baseline FFP yield before intervention. Average nutrient uptake under SSNM increased by about 10% in the same seasons or by 13% (N) and 21% (P, K) compared to the baseline data. Yield increases were associated with a 4% decrease in the average N rate, but larger amounts of fertilizer-K at sites where the previous K use was low. Average N use efficiencies increased by 30–40%, mainly through the use of improved in-season N management schemes. Across all sites and four successive rice crops, profitability increased by US$ 46 ha−1 per crop or 12% of the total average net return. The performance of SSNM did not differ significantly between high-yielding and low-yielding climatic seasons, but improved over time with larger benefits observed in the second year. Average profitability increased from US$ 32 ha−1 pre crop in the first year to US$ 61 ha−1 pre crop in the second year due to improvements in the SSNM approach and re-capitalization of P and K applied in the first year. SSNM required little extra credit for financing, and remained profitable even if rice prices are somewhat lower than current levels. Further, scope for improvement exists at many sites by alleviating other crop management constraints to nutrient use efficiency. Profit increases ranged from US$ 4 to 82 ha−1 per crop among eight rice domains. However, profit decreases occurred in about 25% of all cases, indicating that a certain minimum level of crop care is required for SSNM to be profitable. Yields at sites with labor-saving direct-seeding of larger fields were about 1 Mg ha−1 lower than those achieved at sites with labor-intensive transplanting and good management, raising concern about future trends in rice production. SSNM has potential for improving yields and nutrient efficiency in irrigated rice to close existing yield gaps. The major challenge for SSNM will be to retain the success of the approach while reducing the complexity of the technology as it is disseminated to farmers. The nature of the approach will need to be tailored to specific circumstances in different countries. In some areas, SSNM may be field or farm specific, but in many areas it is likely to be just region and season-specific. [Copyright &y& Elsevier]