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• Performance of a two-stage ARC system using R170/R600a, R170/R600, R1150/R600a, R1150/R600, and R23/R134a was compared. • Under different working conditions, the variation of the maximum COP with the optimal refrigerant ratio was investigated. • R170/R600 afforded the best performance to replace R23/R134a in the ARC system. • Under certain working condition, the exergy loss ratio of each component in the ARC system was analyzed. Auto-cascade refrigeration cycle (ARC) is widely used in low-temperature applications. The selection and proportion of refrigerant mixtures in an ARC system have a significant impact on the environment and system performance. In this study, the theoretical performance of a two-stage ARC system using R170/R600a, R170/R600, R1150/R600a, R1150/R600, and R23/R134a was compared. The results showed that, under certain working conditions in the ARC, an optimal refrigerant ratio maximized the COP of the system. At lower evaporator outlet temperatures or higher condenser outlet temperatures, the performance of the system using R170/R600a, R170/R600, R1150/R600a, and R1150/R600 offers advantages over that when using R23/R134a. Among these, R170/R600 afforded the best performance. Exergy analysis was also performed, and the exergy loss ratios of the heat exchanger in the R170/R600 and R23/R134a systems were the highest at 52.3% and 56.7%, respectively. [ABSTRACT FROM AUTHOR]

Fluorescent probes are essential for optical imaging and have been extensively employed for precise cancer diagnosis studies. β-galactosidase (β-gal) serves as a primary biomarker for ovarian cancer and has been utilized to develop imaging probes for accurate tumor diagnosis. However, traditional small molecular probes have limitations in terms of rapid diffusion and metabolic clearance from the target lesion, resulting in a short imaging window and compromised tumor-to-background ratios (TBR). Herein, we integrated an enzyme-instructed in situ self-assembly strategy to construct Gal-IRFF , a small molecule-based activatable near-infrared (NIR) fluorogenic probe. Upon cleavage by endogenous β-gal overexpressed in ovarian cancer cells, IRFF exhibited enhanced NIR fluorescence signals and self-assembled into nanoparticles through intermolecular interactions of the Phe-Phe (FF) dipeptide moiety, which facilitated probe accumulation and retention within the tumor lesion. Compared with the small molecule probe Gal-IR , our proposed self-assembly probe Gal-IRFF demonstrated a lower limit of detection (LOD) towards β-gal and showed remarkable improvements in distribution and retention time within SKOV3 cells in vitro and tumors in vivo , thereby providing a long-term imaging window for real-time monitoring β-gal levels in ovarian tumors. Therefore, this study highlights the potential of an enzyme-instructed self-assembly fluorogenic probe design approach for achieving precise tumor diagnosis in vivo. The study demonstrates an enzyme-instructed in situ self-assembly fluorogenic probe, Gal-IRFF , enabling efficient monitoring of β-Gal levels both in vitro and in vivo. Upon cleavage by endogenous β-gal overexpressed in cancer cells, the probe exhibits significantly enhanced near-infrared (NIR) fluorescence signals and undergoes self-assembly into nanoparticles, thereby facilitating a prolonged imaging window and precise diagnosis of ovarian tumors. [Display omitted] • In situ self-assembly fluorogenic probe Gal-IRFF was designed based on enzyme-instructed self-assembly (EISA) strategy. • Gal-IRFF self-assembled from small molecules to nanoparticles in the presence of β-gal and exhibited low detection limit. • Gal-IRFF can effectively detect different β-gal levels in SKOV3 and Hela cells with high sensitivity. • Gal-IRFF was characterized with persistent retention ability in cells after activated by β-gal. • Gal-IRFF enabled long-term real-time monitoring endogenous β-gal activities in ovarian tumor-bearing nude mice. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanosheet MoS 2 exhibits high activity and excellent stability in RWGS reaction. • CO desorption is facilitated through electron transfer from Mo to O atoms. • Redox mechanism is involved in MoS 2 and MoS 2 /MoO 2. A nanosheet MoS 2 catalyst is prepared via the hydrothermal method and O incorporation by calcination strategy. The X-ray and BET characterizations show that the calcination results in a considerable increase in crystallinity and specific surface area (from 48.82 to 84.49 m2/g), leading to the efficient adsorption of CO 2. In situ DRIFTS spectra and DFT calculations reveal that redox mechanisms are involved in the RWGS reaction on MoS 2. CO desorption is facilitated by O incorporation through electron transfer from Mo to O atoms and the higher barriers of CO hydrogenation and dissociation. CH 4 formation is effectively suppressed by the edge sulfur vacancies through the weakened adsorption strength of CO. A remarkable CO 2 conversion (57 %) and high stability (>1000 h) are obtained at 600 °C. This performance is superior to those of traditional supported catalysts. This study reports a promising two-dimensional layered material for exploring excellent performance catalysts for the reverse water gas reaction. [ABSTRACT FROM AUTHOR]

• R1270 and carbon dioxide was used in the cascade refrigerant system. • A prototype was manufactured and experimental investigation was carried out. • Two semi-hermetic piston compressors were used for high- and low-temperature circuit. • R1270 had good performance on high-temperature circuit and could be used to replace R22 and R134a. Herein, we proposed a c ascade refrigerant system with R1270 and carbon dioxide refrigerants. The natural refrigerant R1270 was adopted in the high-temperature circuit to replace NH 3 and R290. A prototype cascade refrigerant system with two semi-hermetic piston compressors was manufactured, and its performance was investigated experimentally. The results establish R1270 as a good alternative in the high-temperature circuit of the cascade refrigerant system. Moreover, with a constant condensation and evaporation temperature of cascade system, as the R1270 evaporation temperature was decreased (from −7 °C to −19 °C), the coefficient of performance (COP) of the cascade system increased. The isentropic efficiency of R1270 compressor decreased from 78.5% to 74.7% when the R1270 evaporation temperature increased from −19 °C to −7 °C. [ABSTRACT FROM AUTHOR]

In order to improve the pretreating efficiency of single crystal diamond (SCD) before its homoepitaxial growth, a strategy coupling laser cutting and microwave hydrogen plasma etching was proposed to replace the traditional pretreatment steps, which underwent laser cutting, mechanical polishing, acid cleaning, and microwave plasma etching in order. The feasibility of this idea has been studied by growing SCD after directly etching its laser-cut surface using microwave hydrogen plasma. The effect of the etching time on the SCD including surface phase, etching morphology, etching pit shape, residual stress, growth morphology, and quality of SCD are investigated and analyzed. The results show that microwave hydrogen plasma etching can quickly (within 10 min) remove the residual graphite carbon on the SCD surface caused by laser cutting. The extension of the etching time mainly affects the surface morphology and the internal stress of SCD. Etching pits with different shapes (square, trapezoid, inverted pyramid) and sizes can be found on the hydrogen plasma etched surface under different etching times. Fortunately, these etching pits do not introduce polycrystals on the SCD during subsequent homoepitaxial growth. All the hydrogen plasma etched laser cut SCD samples exhibit typical step-flow growth morphology after 20 h of homoepitaxial growth. Moreover, the step-flows are orderly and parallel, which is better than the disorderly step-flows on the polished SCD. Besides, a higher growth quality and a lower residual stress are obtained for the etched SCD. The above results indicate that replacing the traditional complex pretreatment steps with laser cutting and etching pretreatment is feasible. The new approach can effectively improve the pretreatment efficiency and result in superior quality of SCD after homoepitaxial growth. [Display omitted] • Microwave H plasma etching was directly adopted on the laser-cut surface of SCD. • H etching laser cut surface is to replace traditional multi-step pre-treatment of SCD. • H plasma etching removes defects introduced by laser cutting and leaves etch pits on the surface. • Etching pits will not cause the formation of polycrystals during the homoepitaxial growth. • Higher-quality heteroepitaxial SCD can be grown on the etched laser-cut surface of SCD seeds. [ABSTRACT FROM AUTHOR]

An ultra-short-term wind power forecasting method based on personalized robust federated learning (PRFL) is proposed to exploit spatio-temporal correlation in a privacy-preserving way to facilitate the collaboration between wind farms. Firstly, standard federated learning (FL) with a bidirectional long short-term memory neural network (Bi-LSTM) as the underlying forecasting model is adopted as the primary framework. Secondly, to mitigate FL's vulnerability to anomalies, a Geometric median based federated aggregation scheme is utilized instead of the traditional FedAvg algorithm, enabling enhancement of the robustness against anomalous updates from individual wind farms. Finally, a personalized federated learning (PFL) strategy incorporating transfer learning is proposed to alleviate the challenge of limited model applicability due to data heterogeneity in conventional FL approaches. The case study involving 30 wind farms demonstrates the superior forecasting accuracy of PRFL compared to traditional FL-based methods. In particular, PRFL yields relative improvements ranging from 2.67 % to 7.49 % compared to local forecasting method without spatial correlation, while ensuring data privacy through the local storage of raw data at each collaborative wind farm. Furthermore, empirical examinations incorporating artificially induced anomalous scenarios affirm PRFL's outstanding resilience in handling anomalies during collaborative training, surpassing the capabilities offered by conventional approaches. • A privacy-preserving framework to enable spatial collaboration among wind farms. • Geometric median based federated aggregation method with robustness to anomalies. • Model generalization is enhanced based on transfer learning strategy. • Effectiveness of the method is verified by a case study with 30 wind farms. [ABSTRACT FROM AUTHOR]

• Difference between experimental and setting oscillatory fraction are discussed. • The flow structure under moderate Reynolds number are clarified. • Heat transfer can be better enhanced at high frequency and low oscillatory fraction. Heat transfer enhancement and flow characteristics in grooved channel for pulsatile flow are investigated experimentally and numerically in the present work. The amplitude of the pulsatile flow is focused at different Reynolds numbers and oscillatory fractions by measuring time-varying flow rate through the electromagnetic flowmeter. In addition, the pulsatile flow patterns are visualized through aluminum dust method. The experimental results showed that the oscillatory fraction decreases with frequency of pulsatile flow, which is also proved by the flow visualization results. It is further shown that the amplitude of pulsatile flow can approach the setting value only when the frequency is lower than the critical frequency f c. It is found that the steady and unstable flow states exist in a pulsatile period. The unstable flow enhances fluid mixing between mainstream and recirculation vortex, and the flow mixing increases with the frequency increment, which is the main reason of heat transfer enhancement. Two-dimensional numerical simulations are further carried out to study this problem. The numerical results showed that heat transfer performance is better at high frequency. Moreover, the heat transfer efficiency decreases with oscillatory fraction when frequency is low. Phase shift is found to exist between the pulsatile flow rate, the outlet temperature and the area-averaged wall Nusselt number. Based on the experimental and numerical results, it is found that higher frequency and small oscillatory fraction could cause a better heat transfer performance in the grooved channel. [ABSTRACT FROM AUTHOR]

Abstract The interfacial friction between solid and liquid under applied voltage are vital to actuate droplets. In this paper, the pinning and adhesion force between solid and liquid were measured to study the interfacial friction behaviors under applied voltage. Results showed that the pinning force increased firstly and then decreased with increasing of surface roughness. Moreover, the adhesion forces for the surface with lower roughness were bigger than that for the surface with higher roughness. It suggested that the interfacial friction force was closely associated with the quantity of realigned interfacial water molecules under applied voltage. These findings will extend the understanding of solid/liquid interfacial friction mechanisms under applied voltage, and then to lower the actuation voltage of droplets. Highlights • Solid/liquid adhesion force increased with applied voltage. • Solid/liquid pinning force depended on surface roughness and droplet's wetting states. • The threshold voltage exponentially increased with surface roughness. • The interfacial friction force depended on the quantity of interfacial water molecules. [ABSTRACT FROM AUTHOR]

Highlights • A novel technique to characterize thixotropic behavior of water based MWCNT nanofluids is proposed. • Effect of temperature on viscosity of MWCNT nanofluids has been conducted at three shear rates (5, 50 and 500 s−1). • A new accurate correlation as a function of concentration, temperature and shear rate is proposed. Abstract The rheological properties of water based MWCNT nanofluids are investigated at five different low volume concentrations (0.0047%, 0.0238%, 0.0571%, 0.1428%, 0.2381%) and five low temperatures (275 K, 277 K, 279 K, 281 K, 283 K) by a novel experimental method in the present study. The present methodology combines the 3ITT test and the DSO test. Measurements show that the nanofluids are featured with clear thixotropy and shear thinning behaviors when the concentration is above 0.0571%. It is further shown that the thixotropy becomes less obvious as the concentration lowers implying a stronger Newtonian fluid characteristic. Therefore the concentration of 0.0571% can be regarded as the critical point quantifying the transition from Newtonian to non-Newtonian and this critical concentration is independent of temperature. It is also observed that relative viscosity increases slightly with temperature at medium shear rate. Moreover, temperature sweep measurement suggests that the viscosity decreases with temperature firstly and it increases beyond a critical temperature, which can be curbed by raising the shear rate for solutions with concentration lower than 0.0571%. The dependency of the relative viscosity of the MWCNT nanofluids on shear rate, temperature and concentration is obtained and a new and accurate correlation is developed for engineering application. [ABSTRACT FROM AUTHOR]

Highlights • A novel combined power and ejector refrigeration cycle is proposed. • The proposed cycle is modified based on the solar-assisted OTEC. • Aspen Plus has been used to simulate the performance of the system. • The proposed cycle shows a good energy-saving characteristic. • Thermodynamic evaluation is performed to analyze the effects of some vital parameters. Abstract In this paper a novel combined power and refrigeration cycle is proposed based on the ocean thermal energy conversion (OTEC) system, i.e. the Kalina cycle. In this combined cycle, solar energy is employed to raise the heat source temperature. Cooling capacity is generated concurrently by the ejector refrigeration cycle (ERC) which works on the exhaust heat extracted from the turbine in the Kalina cycle. Ammonia-water and isobutane are selected as the working fluid of Kalina cycle and ERC respectively. To evaluate the performance of the proposed cycle, the process is simulated in the commercial package ASPEN PLUS. It is found that, compared with the Kalina cycle, the proposed cycle has a higher primary energy ratio (PER) of 29.2% though it has a lower power output. Besides, the exergy efficiency and the primary energy saving ratio (PESR) in the proposed cycle reach as high as 41.88% and 8.3% respectively. It is also demonstrated that when the inlet pressure of the turbine exceeds 2.9 MPa and the outlet pressure of the turbine is between 1.3 and 1.6 MPa in the test range, the proposed cycle is better than the stand-alone systems from the energy saving perspective. Furthermore, parametric analysis shows that the inlet and outlet pressure of the turbine, the inlet temperature of the turbine, the basic concentration of ammonia-water, the generation pressure, ejector entrainment ratio and the outlet temperature of the condenser II have significant effects on the output of the turbine, refrigeration output, exergy efficiency, COP , PER as well as PESR. [ABSTRACT FROM AUTHOR]

Abstract The prediction of high-quality reservoirs within tight sandstone is presently a popular and challenging research topic. Many geophysical characteristics of tight sandstone reservoirs are similar to those of the surrounding rock, making it difficult to predict the distribution of these reservoirs. In this paper, a stratigraphic-sedimentological forward modeling is proposed to predict the distribution of high-quality tight sandstone reservoirs in the Xihu Depression, East China Sea. Stratigraphic-sedimentological forward modeling can evaluate the influences of different geological parameters on sedimentary processes and the results. To reproduce the spatial distribution of sedimentary strata in a progradational delta and the overall stratigraphic stacking pattern, different parameters were tested by numerical simulation. According to the influence of the parameters on the sedimentary process, the parameters can be divided into two types: high-sensitivity parameters (transport capacity of the river and sand ratio) and low-sensitivity parameters (maximum initial water depth, lake level change, and tectonic subsidence). The analysis results are suitable for continental sedimentary basins with relatively high deposition rates. In the process of optimizing the simulation parameters, 236 simulations were carried out by adjusting the high-sensitivity parameters and then the low-sensitivity parameters. An optimal model that can reflect the development characteristics of high-quality tight sandstone reservoirs was obtained. According to the characteristics of high-quality reservoirs, the product of the sand ratio and reservoir thickness from the sedimentary simulation results is used as the parameter for evaluating high-quality reservoirs. The ratio can effectively overcome the difficulties of insufficient amounts of data and seismic prediction and effectively predict the locations of high-quality reservoirs in low-exploration areas of tight sandstone reservoirs. This method also provides a new idea for the prediction of high-quality reservoirs in this kind of area in the future. Highlights • Parametric sensitivity analysis shows that river transport capacity and sand ratio are the main factors affecting the model. • Parameter optimization is carried out according to the parameter sensitivity classification. • High-quality reservoirs are predicted by stratigraphic-sedimentological forward modeling. [ABSTRACT FROM AUTHOR]

Fluorescent cuprous iodide (CuI)-based coordination polymers (CuI-CPs) were widely used in the sensor field for high selectivity and sensitivity. Here, a new CuI-CP fluorescent probe was fabricated for the detection of spermine, spermidine and cysteine with dual-mode, which was capable of both convenient colorimetric analysis and ratiometric fluorescent detection. The fluorescence of CuI-CP solution was quenched and the solution changed from white to purple upon addition of spermine or spermidine, while the solution changed from white to yellow for cysteine. This probe exhibited selective, sensitive, rapid and linear response to spermine, spermidine and cysteine with a limit of detection of 0.57, 1.06 and 1.18 μM, respectively. Furthermore, cellulose acetate was used as the matrix to fabricate intelligent fluorescent film for real-time and visual monitoring the freshness of pork samples based on distinct fluorescence changes under UV light. This work realized a rapid, efficient, and profitable method for visually evaluating food quality. This work developed a real-time and visual detection of the freshness of food. [Display omitted] • A novel dual-mode probe was designed for detection spermine, spermidine and cysteine. • The probe exhibits high sensitivity with LOD of 0.57, 0.98 and 1.18 μM, respectively. • The probe was used as colorimetric analysis and ratiometric fluorescent detection. • An intelligent fluorescent film for real-time, visual monitoring freshness of pork. [ABSTRACT FROM AUTHOR]

Peste des petits ruminants (PPR) is a severe infectious disease of small ruminants caused by PPR virus (PPRV). Rapid and sensitive detection of PPRV is critical for controlling PPR. This report describes the development and evaluation of a conventional reverse transcription recombinase polymerase amplification (RT-RPA) assay and a real-time RT-RPA assay, targeting the PPRV N gene. Sensitivity analysis revealed that the conventional RT-RPA assay could detect 852 copies of standard PPRV RNA per reaction at 95% probability within 20 min at 41 °C, and the real-time RT-RPA assay could detect 103 copies of RNA molecules per reaction at 95% probability. Specificity analysis showed that both assays have no cross-reactivity with nucleic acid templates prepared from other selected viruses or common pathogens. Clinical evaluation using 162 ovine and hircine serum and nasal swab samples showed that the performance of both the real-time RT-RPA assay and the conventional RT-RPA assay were comparable to that of real-time RT-PCR. The overall agreements between real-time RT-PCR and real-time RT-RPA, and conventional RT-RPA were 99.4% (161/162) and 98.8% (160/162), respectively. The R 2 value of real-time RT-RPA and real-time RT-PCR was 0.900 by linear regression analysis. Our results suggest that both RT-RPA assays have a potential application in the rapid, sensitive and specific detection of PPRV. [ABSTRACT FROM AUTHOR]

Ag nanoparticles bridged g-C 3 N 4 and WS 2 nanosheets heterojunction (x-y-WAC) and Ag nanoparticles deposited g-C 3 N 4 /WS 2 heterojunction (x-y-AWCA) were prepared through a solvent evaporation and high temperature calcinations method, the x is the percentage of Ag nanoparticles and y is WS 2 nanosheets in mass fraction, respectively. The as-prepared heterojunctions were applied to water splitting for H 2 evolution and NO removal at the indoor air level under simulated sunlight irradiation, in which the H 2 production rate and NO removal efficiency of the bridged structure are much higher than that of deposited structure. The H 2 production rate of most effective samples (2-20-WAC) were measured to be 68.62 μmolh −1 , which are 1.86 and 15.67 times higher than that of pure g-C 3 N 4 and WS 2 nanosheets, respectively. The gradient test of Ag nanoparticles and WS 2 nanosheets indicated that the optimum amounts of Ag nanoparticles and WS 2 nanosheets were 2% and 20% in mass fraction. The morphology of 2-20-WAC heterojunction was characterized by SEM, TEM and HRTEM techniques and the results revealed that the Ag nanoparticles were intercalated into the interlayer of g-C 3 N 4 and WS 2 nanosheets. According to the XRD, FT-IR, UV–vis and XPS analysis, the Ag nanoparticles, g-C 3 N 4 and WS 2 nanosheets are hybrid by chemical bond through the second calcinations. Furthermore, the bridged structure can promote the separation rate of charge carriers and suppress the recombination of them at the same time, which could be deduced from photocurrent and PL investigation. Based on the characterization and results analysis, it can be inferred that the bridged structure can accelerate the transport of charge carriers and restrain the recombination of electrons and holes at the same time，which could improve photocatalytic performance of the heterojunction. [ABSTRACT FROM AUTHOR]

Pleomorphic adenoma (PA), Warthin's tumor (WT) and mucoepidermoid carcinoma (MEC) are three common subtypes of salivary gland tumors, for which the occurrence site is located in the parotid gland. Accurately diagnosing the subtypes of parotid tumors plays a vital role in the surgical treatment. Unfortunately, the current studies mainly focus on the binary classification of parotid tumors. The preoperative multi-classification of them has still been underexplored. For the purpose of broadening the application area of the predictive models and facilitating the clinical preoperative diagnosis, we suggested a multi-classification model, which was constructed by combining the variable combination population analysis (VCPA) algorithm with the partial least squares regression (PLSR), to simultaneously discriminate the three subtypes of parotid tumors as well as the normal parotid gland tissue based on the Raman spectra of the tissue samples. In addition, we investigated the impact of generating Raman spectra from different sampling locations on the reliability of the predictive models. For the validation set, the overall accuracy in predicting the subtypes of parotid tumors and the normal parotid gland tissue was 0.867. Similarly, the accuracies achieved by the models constructed with the Raman spectra from two different sampling locations were 0.877 and 0.883, respectively, indicating the minor influence of the sampling locations on the predictive models. Our findings can be helpful for establishing the method of rapidly diagnosing the salivary gland tumors preoperatively in clinics. Moreover, the characteristic wavenumbers used in model construction were highly associated with the variations of the structures and contents of nucleic acids, collagen, proteins, lipids and DNA/RNA in gland tissue, which revealed the mainly difference among three types of parotid tumors and can be conductive to better understanding the molecular mechanisms of them. [ABSTRACT FROM AUTHOR]

Porcine circovirus 3 (PCV3) is a novel circovirus that was associated with porcine dermatitis and nephropathy syndrome, reproductive failure, and multisystemic inflammation. The objective of this study was to develop a rapid, simple, specific and sensitive TaqMan-based real-time PCR assay for PCV3 detection. Specific primers and probe were designed for the cap gene of PCV3 within the conserved region of viral genome. The assay was highly specific for PCV3, without cross-reactions with other non-targeted pig viruses. The detection limit of this assay was 10 2 copies. The assay had an efficiency of 95.7%, a regression squared value (R 2 ) of 0.994 and showed a linear range of 10 2 –10 7 copies PCV3 DNA per reaction. The assay was also very reproducible, with the intra- and inter-assay coefficient of variation less than 2.0%. For the 112 archived clinical samples collected from 2014 to March 2017, the PCV3 positive ratio was 12.5% (14/112) with the real-time PCR. The presence of the PCV3 dated back to at least 2014 in China and samples collected in 2017 had the highest PCV3 positive ratio (46.7%, 7/15). The real-time PCR assay could be used for detection of PCV3 in epidemiological and pathogenesis studies. [ABSTRACT FROM AUTHOR]

The cycle stability of La-Mg-Ni based alloys in a gas–solid reaction system was investigated in this work. Both partial substitutions of La and Ni by Ce and Al, respectively, improved the cycle stability of La (0.65−x) Ce x Ca 1.03 Mg 1.32 Ni (9−y) Al y alloys. Although the addition of Al reduced the hydrogen storage capacity significantly, it is still important to be included in the system for its superior property in improving the cycle life. Hence, two optimized samples with a small addition of Al (y = 0.10) were used to compare with the cycle life of CaNi 5 . It was found that the Ce and Al added samples have a better hydrogen capacity retention than that of samples without element substitution; and their overall hydrogen storage capacity was still higher than that of CaNi 5 . We also found that heat treatment used in this study did not fully recover the hydrogen storage capability of La-Mg-Ni based alloy to its original storage capacity. A probable reason was the heat treatment used in this study could only recover the degradation caused by the disproportionation to some extent, but the treatment was unable to reverse the degradation caused by decrepitation. [ABSTRACT FROM AUTHOR]

Silver oxide (Ag x O) has huge potential in the catalysts and semiconductor devices applications and thus it is of great significance to characterize its semiconductor properties. Here, by using the RF reactive magnetron sputtering method under different substrate temperatures, 40, 100, and 200 °C, respectively, three Ag x O films were prepared and their semiconductor properties were carefully investigated through X-ray diffraction, Hall measurement, transmittance and photoluminescence spectrum. The main phase of the Ag x O films sputtered at 40 and 100 °C is found to be AgO, while that sputtered at 200 °C is Ag 2 O. The resistivity of the Ag x O films increases with the substrate temperature and the mobility of the AgO films are about 21 and 15 cm 2 /V·s for the 40 and 100 °C deposited films, respectively. Photoluminescence measurement results suggest that the band gaps of Ag 2 O and AgO films are both 3.4 eV, and the emission bands in the visual light region indicate the existence of amount of defects in the Ag x O films. Moreover, the defect levels in the band gap deduced from the transmittance spectra are consistent with that from the photoluminescence spectra analysis. Besides, a metal-metal-semiconductor-metal structured X-ray detector was fabricated using the high-resistivity Ag 2 O film to explore its photoconductive response to the X-ray. The signal to noise ratio is 65 and the sensitivity is 4.2 nC/Gy at 5 V bias voltage using the 30 kV X-ray source with the dose rate of 1.53 Gy/s. [ABSTRACT FROM AUTHOR]

Large-scale integration of wind energy into power systems may cause operational problems due to the stochastic nature of wind. A short-term wind power prediction model based on physical approach and spatial correlation is proposed to characterize the uncertainty and dependence structure of wind turbines' outputs in the wind farm. Firstly, continuous partial differential equation of each wind turbine has been developed according to its specific spatial location and the layout of its neighboring correlated wind turbines. Then, spatial correlation matrix of wind speed is derived by discretizing differential equation at each wind turbine using a finite volume method (FVM). Wind speed at each turbine is acquired by solving the relevant differential equation under given boundary conditions. Finally, the wind speed is converted to wind power production via a practical power curve model. Prediction results showed that the spatial correlation model can accurately characterize the correlations among outputs of wind turbines and reduce the error of short-term wind power prediction. [ABSTRACT FROM AUTHOR]

• A novel three-stage RACR was proposed to improve the performance of ACR. • The R134a/R23/R14 RACR system performed better than the ACR system. • The influence of the refrigerant ratio on RACR performance was investigated. • Different hydrocarbons were provided as alternatives to R134a and R23. • R600/R170/R14 performed the optimum performance in the RACR system. Auto-cascade refrigeration (ACR) systems are widely used at low temperatures. The selection and ratio optimization of zeotropic refrigerants in ACR systems have an important impact on system performance and environmental protection. This study proposes a three-stage regenerator-enhanced auto-cascade refrigeration (RACR) system. Under certain working conditions, the theoretical performances of the three-stage R134a/R23/R14 ACR and RACR systems were compared, and the influence of the refrigerant mixture ratio on the RACR system performance was explored. The system performances of replacing R134a and R23 with different hydrocarbons were compared under different working conditions. The results demonstrated that RACR performed better than ACR alone. A reasonable adjustment to the mixed refrigerant ratio improved the energy efficiency of the RACR system. Water-cooling conditions for the RACR system were suggested, under which the coefficient of performance, thermodynamic perfectness, and exergy efficiency of R600/R170/R14 were 13.8 %, 12.4 %, and 8.4 % higher than those of R600/R23/R14, respectively. The environmental policy, safety requirements, and energy efficiency were considered to obtain −100 °C, R600/R170/R14 with mass fractions of 0.24/0.12/0.64 was the best choice in a water-cooled RACR system. [ABSTRACT FROM AUTHOR]

To know differences in oxidation resistance and mechanical properties between Al 2 O 3 -forming and SiO 2 -forming austenitic stainless steels, oxidation behavior and mechanical properties were investigated in Fe-20Ni-14Cr-3Al-1Nb-0.1C, Fe-20Ni-14Cr-5Si, and Fe-20Ni-14Cr-3Si-1Nb-0.1C (in wt%) steels. The results showed that the oxidation resistance of Fe-20Ni-14Cr-3Si-1Nb-0.1C steel was comparable to that of Fe-20Ni-14Cr-3Al-1Nb-0.1C steel at 1023–1073 K but poor at 1123 K. The addition of Nb could improve the oxidation resistance in the SiO 2 -forming steels. The solution-treated and oxidized SiO 2 -forming steels showed remarkably higher ductility but lower yield strength than the Al 2 O 3 -forming steel did. The easier twinning and fewer precipitates were responsible for the remarkably higher ductility in the SiO 2 -forming steels. • Oxidation resistance of the AFA steel and SFA steels were comparable at 1023–1073 K. • Continuous SiO2 scales were observed at the metal/oxide interface. • The addition of Nb could improve the oxidation resistance in the SFA steel. • The solution-treated and aged SFA steels showed a higher ductility but a lower strength than the AFA steel did. [ABSTRACT FROM AUTHOR]

Probabilistic estimation of dietary exposure to DON, including its acetylated derivatives, and type B trichothecenes from cereals and cereal-based products in Chinese populations was investigated in the current work. Different cut-offs as proposed Maximum levels (MLs) for DON in various raw cereals and/or cereal-based foods were assessed based on the risk assessment results. Occurrence data was documented from 31 provinces of China over the year 2010–2013. Food consumption data was obtained from the National Diet and Nutrition Survey conducted in 2002. Dietary exposure was implemented by Monte Carlo (MC) simulations and Bootstrap resampling. The exposure distributions were specified as percentiles with confidence intervals (95% CIs) and compared with the group provisional maximum tolerable daily intake (PMTDI) of 1 μg/kg bw/day and the group acute reference dose (ARfD) of 8 μg/kg bw/day for DON and its acetylated derivatives. Results indicate that 75% of children and 90% of the general population and the adults are under the group PMTDI value, while 99% of the three populations are under ARfD value. However, under the assumptions of the proposed cut-offs, the P99.9 percentiles would decrease significantly. The probabilistic assessment in this study indicated that high-end exposure to DON and its derivatives should be concerned, especially for children. Rigorous formulation of maximum limits for DON and its derivatives in the relevant foodstuffs combined with increased monitoring should be considered as an effective way to reduce risk. [ABSTRACT FROM AUTHOR]

A novel bidirectional mechanism and a backward forecasting model based on extreme learning machine (ELM) are proposed to address the issue of ultra-short term wind power time series forecasting. The backward forecasting model consists of a backward ELM network and an optimization algorithm. The reverse time series is generated to train backward ELM, assuming that the value to be forecasted is already known whereas one of the previous measurements is treated as unknown. In the framework of bidirectional mechanism, the forward forecast of a standard ELM network is incorporated as the initial value of optimization algorithm, by which error between the backward ELM output and the previous measurement is minimized for backward forecasting. Then the difference between forward and backward forecasting results is used as a criterion to develop the methods to correct forward forecast. If the difference exceeds a predefined threshold, the final forecast equals to the average of forward forecast and latest measurement. Otherwise the forward forecast keeps as the final forecast. The proposed models are applied to forecast wind farm production in six time horizons: 1–6 h. A comprehensive error analysis is carried out to compare the performance with other approaches. Results show that forecast improvement is observed based on the proposed bidirectional model. Some further considerations on improving wind power short term forecasting accuracy by use of bidirectional mechanism are discussed as well. [ABSTRACT FROM AUTHOR]

La–Mg–Ni based alloys have a high hydrogen storage capacity, but their cycle stability is usually poor. In this work, a series of composites were synthesized by mixing La–Mg–Ni based alloys with a commercial AB 5 type alloy. The aim was to investigate the effects of AB 5 additions and ball milling treatment in improving the cycle stability of La–Mg–Ni based alloys, while maintaining a substantial and reversible hydrogen storage capability. It was found that the cycle stability was greatly influenced by the amount of AB 5 added, but the effect of ball milling pre-treatment was small. While the increase in AB 5 content was beneficial, the cost of the composite also went up accordingly. In light of these challenges, a feasibility study was conducted to optimize the compositions. The results suggested that the composite with a 50 wt% of AB 5 addition was the optimum compositions in maximizing the hydrogen storage capacity and cycle stability, while minimizing the cost up to 20% as compared with AB 5 alone. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C 3 N 4 ) nanosheets with few-layer and single-layer structures were prepared by a simple chemical exfoliation method. The samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, UV–vis absorption spectroscopy and photoluminescence spectroscopy, respectively. The investigations indicated that the bulk g-C 3 N 4 can be easily exfoliated into g-C 3 N 4 nanosheets with few-layer structure under the assistance of HNO 3 . The specific surface area of few-layer g-C 3 N 4 reached 179.5 m 2 g −1 , which was about 10.3 times higher than that of bulk g-C 3 N 4 (17.4 m 2 g −1 ). The absorption edge of few-layer g-C 3 N 4 nanosheets showed a blue shift from 486 nm to 458 nm, corresponding to an increase in the band gap from 2.55 eV to 2.70 eV compared with that of bulk g-C 3 N 4 . In addition, the position of the emission peak of few-layer g-C 3 N 4 was blue shifted from 461 nm to 439 nm. The photocatalytic performance of samples was evaluated by the degradation of methylene blue and the photocatalytic water splitting under visible light irradiation. The experimental results indicated that the degradation rate of MB on few-layer g-C 3 N 4 nanosheets was about 1.3 times higher than that of bulk g-C 3 N 4 , the H 2 production rate reached 110.68 μmol g −1 h −1 over g-C 3 N 4 nanosheets, which was 1.22 times higher than that of bulk g-C 3 N 4 . [ABSTRACT FROM AUTHOR]

In this study, a vapor injection technique was applied in a high temperature heat pump (HTHP) for providing hot water at temperatures up to 88 °C. A prototype HTHP system with economizer vapor injection was developed and its performance was experimentally investigated under various operating conditions. Results showed that the vapor injection pressure had a large effect on heating capacity and on refrigerant temperature at the inlet of the electronic expansion valve (EEV). As the injection pressure increased from 0.82 to 0.98 MPa, the vapor injection flow ratio increased from 7.3% to 22.61% and the heating capacity increased by 7%. The system COP did not show significant change although the COP trend showed an optimal value for the injection pressure. The refrigerant temperature at the EEV inlet showed a subcooling of more than 16 °C under all studied conditions, which improved the EEV operating reliability. [ABSTRACT FROM AUTHOR]

We have fabricated the X-ray detector based on the α- Zn 2 SiO 4 film. The Zn 2 SiO 4 film was prepared by the solid state reaction of ZnO film and quartz substrate at 1200 °C. The fabricated detector has a rapid and steady response to X-ray irradiation and shows a light-to-dark-current ratio more than 10 3 under the applied bias of 30 ∼ 200 V (dose rate 0.415 Gy/s). The response current increases sublinearly with the X-ray intensity which can be attributed to trap centers in the film. It is indicated that Zn 2 SiO 4 can be a candidate material for the development of compound semiconductor X-ray detector. [ABSTRACT FROM AUTHOR]

The cross section of the 60 Ni( n ,2 n ) 59 Ni induced by neutron with energy around 14 MeV is important for a fusion environment. However, the published values are strongly discordant. By taking advantage of the high sensitivity of 59 Ni measurement at China Institute of Atomic Energy (CIAE), determination of the cross section has been carried out. A natural Nickel foil was irradiated by neutrons produce by a T(D, n ) α neutron generator. 57 Co and 58 Co which produced in the Nickel foil were chosen for the neutron fluence determination. Then the ratio of 59 Ni/ 60 Ni for the irradiated sample was determined via accelerator mass spectrometry (AMS) utilizing a 13MV tandem accelerator and a Q3D magnet spectrometry at CIAE. As a result, the cross section of 60 Ni( n ,2 n ) 59 Ni for the incident neutron energy of (14 . 60 ± 0 . 40) MeV was determined to be (426 ± 53) mb. [ABSTRACT FROM AUTHOR]

Many previous behavioral inhibition studies have employed the classic Stroop and reverse-Stroop paradigm. Although an experimental dissociation has been demonstrated between Stroop interference (SI) and reverse-Stroop interference (RI), the mechanisms that underlie these phenomena remain unclear. In this study, we used functional magnetic resonance imaging (fMRI) to compare the functional mechanisms of SI and RI. We identified the brain regions activated by the Stroop word-color matching task using four tests: the Stroop control test (Test 1), Stroop test (Test 2), reverse-Stroop control test (Test 3), and reverse-Stroop test (Test 4). Neuroimaging results revealed that SI elicited activation in the bilateral middle frontal gyrus (BA9). In contrast, a number of other regions, including the bilateral middle frontal gyrus (BA 9 and BA10), medial frontal gyrus (BA 8), and cingulate gyrus (BA6 and BA 32) exhibited significant activation during RI. Our results indicate that there is a dissociation between the types of interference and brain activation. These findings suggest that SI and RI interference can be attributable to different neural mechanisms. It also suggests that the prefrontal cortex and the cingulate cortex are differentially sensitive to various types of interference, and that the reverse-Stroop task may be more useful than the Stroop task for evaluating interference control in psychiatric patients with frontal dysfunction. [ABSTRACT FROM AUTHOR]

To design near-infrared (NIR) absorbing photosensitizing compounds, we theoretically elucidated the geometrical structures and electronic transition properties of four porphyrin-based and four phthalocyanine-based derivatives. The results show that fusion of a π-conjugated aromatic ring with the pyrrole rings of porphyrin can cause the larger red-shifts in the Q-bands than π-conjugated groups in the meso positions of porphyrin do. The extent of the red-shift of the absorption bands induced by the coordinated metal atom depends on the electrons occupied in their outer shell. The electron-donating groups also affect the absorption properties of porphyrins due to the σ → π bond formed between the donor groups and the porphyrin ring. Based on these calculated results, we found a phthalocyanine-based compound containing Ti metal that has an absorption wavelength of 977.5 nm and a molar extinction coefficient of 10 4 L/mol cm. Moreover, the intrinsic reasons for the significant absorption properties for the phthalocyanine-based compounds were revealed. [ABSTRACT FROM AUTHOR]

Present proposed mechanisms for ageing-induced martensitic stabilization cannot explain why the amount of martensites losing reverse transformation ability (RTA) positively depended on M s temperatures in directly-quenched CuZnAl alloys owing to dynamic ageing during the cooling process of quenching and subsequent slow heating. We proposed and confirmed that the number of vacancies at martensites boundaries (N vmb) was the key factor controlling the occurrence of martensitic stabilization and its resulting RTA or loss in shape memory effect, not the number of vacancies inside the martensites and their long-range diffusion. All reported results can be rationalized by the positive dependence of original N vmb on the M s temperature. • The number of vacancies on martensites boundaries controls the occurrence stage and degree of martensitic stabilization. • The number of vacancies on martensites boundaries positively depends on M s temperature. • The occurrence of vacancies clustering is in direct proportion to the number of vacancies on martensites boundaries. • Critical temperature for vacancies movement and clustering in CuZnAl alloys with M s ≥ 350 K was 250 K. [ABSTRACT FROM AUTHOR]

Previous work did not identify occurrence stage and degree of martensitic stabilization in Cu-based shape memory alloys due to lower heating rate. By flash heating into liquid metals, we systematically clarified contribution of static ageing and the ones of dynamic ageing during process of quenching and heating to the martensitic stabilization in directly-quenched CuZnAl alloys. We discovered that the dynamic ageing during the cooling process of quenching could instantaneously stabilize a few already formed martensites totally although it did not stabilize the overwhelming majority of martensites. The dynamic ageing during the process of subsequent slow heating was responsible for the partial and total stabilization of overwhelming majority of martensites. Both the amounts of martensites stabilized totally by the two dynamic ageing positively depended on M s temperature. The conventional up-quenching into oil or air actually made more martensites stabilized due to the dynamic ageing during the process of slow heating. The increase in A s temperature owing to the static ageing also positively depended on the M s temperature. These dependences cannot be explained by two well-known mechanisms for the martensitic stabilization. • Liquid metals were used as heating media to avoid the occurrence of dynamic ageing during the process of slow heating. • The dynamic ageing during the process of slow heating was responsible for the stabilization of the majority of martensites. • The amounts of martensites losing the RTA induced by ageing processes positively depended on the M s temperatures. • It was the slow heating that made statically-aged martensites lose the RTA in the directly-quenched CuZnAl alloys. • The traditional up-quenching treatments into oil and air actually made more martensites lose the RTA in CuZnAl alloys. [ABSTRACT FROM AUTHOR]

Contrast-enhanced C-arm CT is routinely used for intra-operative guidance during the trans-catheter aortic valve implantation (TAVI); however, the requirement for contrast agent injection is not preferable, especially for patients with renal insufficiencies. To address this problem, we present a novel framework for fully automatic registration of pre-operative CT and non-contrast-enhanced C-arm CT. The proposed framework provides an improved workflow and minimizes the usage of contrast agent in the TAVI procedure. Our framework consists of three steps: coarse rigid-body alignment, anatomical knowledge-based prior deformation field generation, and fine deformable registration. We validated the proposed framework on 20 real patient data sets. Based on the 20 data sets, the mesh-to-mesh errors at the aortic root from different methods are measured. Our proposed method significantly outperforms the other state-of-the-art methods. Specifically, we achieve the registration accuracy at 1.76 ± 0.43 mm which is clinically plausible. Quantitative evaluation on real non-contrast enhanced C-arm CT data sets confirms the applicability in the clinical usage. The proposed heart registration method is generic and hence can be easily applied to other cardiac applications. [ABSTRACT FROM AUTHOR]

Vibrio parahaemolyticus is a ubiquitous marine bacterium that has become an important public-health concern worldwide. Consumption of food contaminated with V. parahaemolyticus causes acute gastroenteritis in humans. To gain understanding of epidemiological characteristics of V. parahaemolyticus gastroenteritis outbreak in China, we summarized data on 2003-2008 V. parahaemolyticus gastroenteritis outbreaks in 12 provinces reported to China National Foodborne Diseases Surveillance Network. A food item was implicated if V. parahaemolyticus was isolated from food or based on epidemiologic evidence. From 2003 to 2008, 322 gastroenteritis outbreaks due to V. parahaemolyticus were reported, resulting in 9041 illnesses and 3948 hospitalizations. Outbreak size ranged from 2 to 244 cases, with a median of 20 cases. Most of the outbreaks occurred during April and October. A single food commodity was implicated in 187 (58%) outbreaks, of which 58 (31%) involved meat and meat products, and 52 (28%) involved aquatic products. Outbreaks most frequently occurred in restaurants (39%), cafeterias (30%), and private residences (15%). Outbreaks most frequently attributed to cross contamination (50%). To prevent and control V. parahaemolyticus gastroenteritis outbreaks, food workers and consumers should receive training on avoiding cross contamination of ready-to-eat foods with uncooked seafoods, particularly in warm weather months. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogen in metal hydrides could be one of the promising energy storage mediums to address the intermittent nature of renewable energy. To convert the hydrogen energy to electricity, the storage system has to be coupled with a fuel cells system. Hence, it is important to design a hydrogen storage system that meets the operating requirements for a fuel cell system. In this work, the effects of partial substitution of both cerium and aluminum on the hydrogenation properties of La(0.65−x)Ce x Ca1.03Mg1.32Ni(9−y)Al y alloys were investigated simultaneously using factorial design. Both Ce and Al additions greatly improved the reversibility of hydrogen storage capacity. However, the maximum hydrogen storage capacity and absorption kinetics can be reduced by the additions. As Ce and Al gave opposite effects on the absorption and desorption plateaus, they could be used to tune the properties of the alloys to the desired operating conditions for fuel cell applications. [Copyright &y& Elsevier]

A higher yield strength of parent phase in shape memory alloys is necessary for achieving a higher recovery stress. Fe alloying combined with grain boundary engineering (GBE) were investigated to improve the yield strength of ductile Cu17Al11Mn alloy. Results showed that the precipitation of low strength ductile α phase through the GBE remarkably enhanced the ductility while not obviously reducing the yield strength in the step-quenched Cu17Al11Mn4.5Fe alloy due to the precipitation of nanoscale κ phase inside them. Compared to the Cu17Al11Mn alloy, a 200 MPa higher yield strength and better ductility could be realized in the Cu17Al11Mn4.5Fe alloy step-quenched into two-phase region between 993 K and 1003 K. The recovery strains of ∼6.5% could be guaranteed in the step-quenched Cu17Al11Mn4.5Fe alloy. The Fe alloying combined with the GBE through the step-quenching will be a direction for developing ductile CuAlMn based alloys with both high strength and recovery strain. [ABSTRACT FROM AUTHOR]

Highlights: [•] A prototype of transcritical CO2 heat pump water heater was introduced. [•] Experiment was conducted for a prototype of transcritical CO2 heat pump water heater. [•] Simulation was conducted for two categories of gas coolers. [•] Variation of the optimal pressure with heat transfer area was illustrated. [•] Variation of the optimal pressure with CO2 mass flux was illustrated. [ABSTRACT FROM AUTHOR]

Highlights: [•] PEDOT surface coating is used to improve the recovery speed of ZnO nanowire based SAW UV detector. [•] The detailed physical mechanisms and processes of the improvement of the recovery speed are analyzed theoretically. [•] The fundamental method to improve the performance of the ZnO nanowire based SAW UV detector is illustrated. [Copyright &y& Elsevier]

Abstract: Direct methanol fuel cells (DMFCs) are a promising power source for mobile devices. However, DMFCs currently experience the technical shortcomings of high cost due to the use of noble metal catalysts and polymer electrolyte membranes (PEMs), low power density because of their low catalytic efficiency and cathode catalyst poisoning by methanol, which crosses through the PEM from anode to cathode. Here, we report a new DMFC structure utilizing a polymer fiber membrane (PFM), which is electrolyte-permeable, instead of a PEM. An inexpensive perovskite-type oxide, LaNiO3, is used as the cathode catalyst, which has shown excellent tolerance to methanol-poisoning and good catalytic activity for oxygen reduction reaction (ORR). The peak power density can reach 103 mW cm−2 at 65 °C. This improvement in performance is due to the lower electrical resistance of the PFM. [Copyright &y& Elsevier]

Abstract: This review summarizes the most recent scientific literature and regulations regarding analytical chemistry, toxicology, epidemiology, exposure, and risk assessment of melamine in infant formula. For analyses, enzyme-linked immunosorbent assay, high-performance liquid chromatography, capillary electrophoresis, gas chromatography coupled with mass spectrometry and liquid chromatography coupled with tandem mass spectrometry have commonly been used. Organization of proficiency test programs provided good evidence to facilitate granting laboratories accreditation and to ascertain the measurement reliability of melamine methods. Metabolic studies demonstrated that melamine is predominantly restricted to blood or extracellular fluid and is not extensively distributed to organs and tissues. Studies of human renal histopathology and clinical diagnoses indicated that melamine-related obstructive nephropathy derives from melamine precipitation in the lower urinary tract, with stones that are thought to be melamine–uric acid complexes. Epidemiologic studies showed that the occurrence of melamine-related urolithiasis is related to both the concentration of melamine in ingested milk products and the duration of ingestion. Long-term follow-up cohort studies should be continued to further investigate the epidemic and chronic hazard of melamine-induced nephrotoxicity. The World Health Organization set a tolerable daily intake of 0.2mg/kgbw/day to be applied to “the whole population including infants”. Other authorities and research institutes have set/proposed lower values. [Copyright &y& Elsevier]

Abstract: The type of fluid, the shape of wavy-walled tube, and the flow field have important impacts on mass transfer. Pressure difference, mass transfer rate, and flow visualization experiments were carried out in wavy-walled tubes of different shapes with purified water and polyacrylamide (PAM) solution for both steady and pulsatile flow. Based on the experimental results, it was found that the effect of mass transfer is enhanced with increasing amplitude of wavy-walled tubes at the same net Reynolds number and that fluid mixing with PAM solution is better than that with water extract for both steady and pulsatile flow. Stable and unstable flow pattern states were found in the wavy-walled tube during a single oscillation cycle. Mass transfer rate and fluid mixing under pulsing flow conditions were better than those under steady flow conditions at the same net Reynolds number, which means that mass transfer was enhanced significantly under pulsatile flow. [Copyright &y& Elsevier]

Abstract: The determination of citrinin (CIT) by a microsphere-based flow cytometric immunoassay (MFCI) has been developed. In the method, the carboxyl-modified microspheres were conjugated with CIT-Ovalbumin (OVA) antigen. CIT competed with the CIT-OVA antigen on the surface of the microspheres for the anti-CIT McAb. Under the optimised conditions, IC50 value was 1.0ng/mL and the limit of detection reached 0.005ng/mL. The cross-reactivity was less than 0.01% against each of the four mycotoxins such as aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEA), deoxynilvalenol (DON). In the work, the MFCI could accurately determine CIT in the real red yeast rice. The systematic error was low with the coefficient of variation (CV) from 5.24% to 8.16% by the MFCI. The mean recovery of CIT from artificially contaminated red yeast rice was from 89% to 94%, with CV from 7.2% to 8.7%. The experimental data showed that the precision, sensitivity and specificity of the developed MFCI method for the determination of CIT were satisfactory. [Copyright &y& Elsevier]

Iodine deficiency disorders were prevalent in China until the introduction of universal salt ¡odization in 1995. Concerns have recently arisen about possible excess iodine intake in this context. To document iodine intake and the contribution from iodized salt in China, we surveyed dietary iodine intake during China's nationally representative 2007 total diet study (TDS) and during an additional TDS in 4 coastal provinces and Beijing in 2009. Iodine intake was broken down by age and sex in 2009. Mean daily iodine and salt intake and the contribution from different food and beverage groups (and in 2009, individual items) was measured. The iodine in food cooked with iodized and noniodized salt was also assessed. The mean calculated iodine intake of a standard male in China was 425 μg/d in 2007 and 325 μg/d in coastal areas in 2009, well below the upper limit (UL) in all provinces. In 2009, iodine intake was above the UL in only 1-7% of age-sex groups, except among children (18-19%). A concerning number of individuals consumed less than the WHO-recommended daily allowance, including 31.5% of adult women. Salt contributed 63.5% of food iodine, and 24.6% of salt iodine was lost in cooking. Overall salt consumption declined between the surveys. Salt iodization assures iodine nutrition in China where environmental iodine is widely lacking. The risk of iodine excess is low, but planned decreases in salt iodization levels may increase the existing risk of inadequate intake. Regular monitoring of urinary iodine and more research on the impact of excess iodine intake is recommended. [ABSTRACT FROM AUTHOR]

Abstract: The surface acoustic wave (SAW) ultraviolet (UV) detector based on zinc oxide (ZnO) nanowire sensing layer was developed and fabricated in this paper. To improve the SAW device''s response characteristics, inter-digital transducers (IDTs) apodized by Morlet wavelet function and multiple couplers (MSC) were applied. ZnO nanowire materials were synthesized by Zinc thermal evaporation method. The ZnO nanowire sensing layer was coated onto the propagating area of the SAW devices, namely the sensing area, by transfer method as well as the multi-crystal ZnO sensing layer was deposited onto another device by magnetron sputtering for comparison. It was found that ZnO nanowire layer itself shows enhanced UV photoelectric response characteristics compared to sputtered ZnO film layer, which is acquired by characterizing their optical and photoelectrical properties. Under illumination of a UV light source, central frequency shifts of the two UV detectors were measured. An average central frequency shift of over 65kHz of the UV detector based on ZnO nanowire layer was observed under 150μW/cm2 365nm illumination for several on–off cycles while the one of the other detector was only about 8kHz. Moreover, the results indicate that the ZnO nanowire layer based SAW UV detector has good stability and repeatability. This kind of SAW UV detector with high sensitivity presents the potential for practical UV detection applications. [Copyright &y& Elsevier]

Abstract: Background: It has been debated whether attending to a particular facial region, such as the eyes, is impaired in children with autism. The purpose of this study was to verify the poor eye gaze hypothesis postulating that children with High-Functioning Autism (HFA)/AS are impaired in their ability to attend to another’s eyes. Methods: Our study used the “Bubbles” method. A group with ASD (n =15) and a paired non-ASD group (n =18) completed an identity judgment task requiring a binary judgment of the identity of a person in an image, and an emotion judgment task requiring perception of expressed happiness in a facial image. Results: Results indicated that similar to non-ASD individuals, ASD individuals used information from other people’s eyes to judge identity as well as emotion, and performed as successfully as the non-ASD group both in identity and emotion judgment tasks. The results challenge the conventional hypothesis that individuals with ASD cannot attend to or derive information from another’s eyes. Conclusion: Our findings combined with the results of poor eye gaze to expressions of fear in previous studies suggest that ASD individuals can derive information pertaining to positive emotion, but cannot sufficiently extract information pertaining to negative emotion from another’s eyes. [Copyright &y& Elsevier]

Abstract: Diet is an important source of perfluorinated compound (PFC) exposure and seafood is an important diet component for coastal populations. Therefore, it is necessary to monitor the concentrations of PFCs in seafood. In this study, we measured thirteen PFCs in 47 fatty fish and 45 shellfish samples collected from six coastal provinces in China (Liaoning, Shandong, Jiangsu, Zhejiang, Fujian, and Guangdong), using an ultra-performance liquid chromatography and tandem mass spectrometry (UPLC–MS/MS). Perfluorooctanesulfonate (PFOS) was the dominant PFC in fatty fish which accounted for 38% of total PFCs, whereas perfluoroctanoic acid (PFOA) was the predominant PFC in shellfish. Concentrations of PFOS were ranged from less than 1.4 to 1627pg/g wet weight in fatty fish, with the highest concentration in red drum from Jiangsu. Concentrations of PFOA in shellfish ranged from less than 5.4 to 7543pg/g wet weight, with the maximum concentration found in briny clam also from Jiangsu. Compared with other studies, the PFC levels in seafood collected from our studied areas are relatively low. The estimated dietary intakes (EDI, pg/kg body weight /day) of PFOA, PFOS and total PFCs for the reference man (63kg body weight) were calculated by multiplying the mean concentrations (pg/g wet weight) of PFOA, PFOS and total PFCs in six coastal provinces with the daily consumption data (g/day) from the fourth Chinese total diet study carried out in 2007. The highest EDI of PFOS and PFOA were found to be 694pg/kg body weight/day and 914pg/kg body weight/day in Guangdong and Jiangsu, respectively. However, the highest EDI of total PFCs was found in Fujian at 2513pg/kg body weight/day. The EDI from seafood is much lower than the tolerable daily intake (TDI) recommended by the European Food Safety Authority in 2008 indicating low health risk of PFC exposure via eating seafood among the coastal populations in China. [Copyright &y& Elsevier]

Abstract: ZnO nanowires have been shown to have high sensitivity for detecting UV light. In this paper, we report a low-cost fabricated metal–semiconductor–metal (MSM) structure, consisting of ZnO nanowire array as outer-layer photo absorber supported by a ZnO nanocrystalline film. The ZnO film is bridged between two electrically interdigitated metal electrodes for collecting photo-generated charges. Different from previous approaches, in which nanowires were directly connected with two metal electrodes , our MSM structure allows direct exposure of dense ZnO nanowires to UV light. In such a way, the outer ZnO nanowires serve as antireflective traps, and the ZnO film are used for both charge transport and seeding ZnO nanowire array self-assembly growth. The photoresponse characteristics for the detector were measured in detail and then the carriers transport model was given to explain the theoretical mechanism for the enhanced photocurrent. The oxygen exchange processes were suggested to be responsible for the slow transient properties. Finally, nanowire surfaces were modified using surface passivation with polymer and Ar ion bombardment to verify the surface depletion effect. It has been shown that transient response for the detector with the polymer passivation become much faster than that original one without the passivation. [Copyright &y& Elsevier]

Abstract: A classic finding in perception of compound patterns is normal individuals cannot skip global analysis in local-oriented processing, but they can successfully resist local analysis in global-oriented processing—the so-called global interference . Recently, studies examining the role of brain hemisphere activity in the Navon task have indicated that the processing of global and local information can be, respectively, attributed to the right and left hemispheres. Moreover, many neuroimaging researches have revealed that certain core symptoms of attention deficit hyperactivity disorder (ADHD) are related to dysfunction of right hemisphere. These findings imply that global interference will be substantially less evident, and possibly even replaced by local interference in ADHD. The present study compared the performance of children with and without attention deficit hyperactivity disorder of the inattentive type (ADHD-I) in the processing of global and local information to examine the local interference hypothesis in ADHD. An ADHD-I group (n =15) and a paired control group (n =19) completed tasks using two versions of the Navon task, one requiring divided attention, in which no information was given to participants regarding the level at which a target would appear, and the other requiring selective attention, in which participants were instructed to attend to either the local or the global level. The results showed that children with ADHD-I exhibited local interference, regardless of which attention procedure was used. These results support the weak right hemisphere hypothesis in ADHD, and provide evidence against the deficit hypotheses for ADHD in the DSM-IV criteria , which postulates that inattention symptoms may manifest as a failure to provide close attention to details. [Copyright &y& Elsevier]

Abstract: In this paper, cobalt(II) oxide (CoO) has been used as an anode catalyst in a direct borohydride fuel cell (DBFC). The microstructure of CoO has been characterised by X-ray diffraction. The cell performance and short-term performance stability of the DBFC using the CoO as anode catalyst have been investigated. At the optimum conditions, the maximum power density of 80mWcm−2 has been achieved at 30°C for this cell without using any precious metals and ion exchange membranes. Results from XRD, TEM, and XPS analysis confirm that the good performance of the fuel cell is attributed to the co-operation of CoO and CoB which formed from CoO during the operation. [Copyright &y& Elsevier]

Abstract: Direct borohydride fuel cells (DBFCs), with a series of perovskite-type oxides La1−x Sr x CoO3 (x =0.1–0.5) as the cathode catalysts and a hydrogen storage alloy as the anode catalyst, are studied in this paper. The structures of the perovskite-type catalysts are mainly La1−x Sr x CoO3 ( x =0.1–0.5) oxides phases. However, with the increase of strontium content, the intensities of the X-ray diffraction peaks of the impure phases La2Sr2O5 and SrLaCoO4 are gradually enhanced. Without using any precious metals or expensive ion exchange membranes, a maximum current density of 275mAcm−2 and a power density of 109mWcm−2 are obtained with the Sr content of x =0.2 at 60°C for this novel type of fuel cell. [Copyright &y& Elsevier]