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Using fund returns and fund stockholdings, we investigate whether fund managers follow fundamental analysis strategies. We show that hedge fund and mutual fund returns tend to load negatively on the long-short returns of a comprehensive sample of fundamental strategies (i.e., accounting anomalies), suggesting that fund managers are prone to trade in the opposite direction of what fundamental strategies prescribe. The negative loadings are primarily driven by the short-leg of the anomalies, more pronounced for contrarian-like anomalies, and more prevalent among earnings quality, investment, external financing, value, and profitability-based anomalies. We show that funds with higher anomaly loadings perform significantly better. Our results suggest that fund managers, as a group, do not systematically pursue fundamental analysis strategies, perhaps due to agency concerns, but a subset of managers are skilled and profit from employing such strategies. We find similar results when examining the stockholdings of hedge funds and mutual funds. Our findings have important implications for the persistence of accounting anomalies, sophistication of institutional investors, and investment value of fundamental analysis. [ABSTRACT FROM AUTHOR]

SiOC is a competitive alternative anode for lithium ion batteries attributing to the high specific capacity and advanced structural stability during cycling. However, it suffers from the intrinsically poor electrical conductivity, thus leading to an inferior high-rate performance and poor cyclability. Herein, we synthesized SiOC/C hybrids through a simple method with high cost-efficiency, which contains blending the polymerized product of phenyl triethoxy silane with asphalt and sequent pyrolysis. The obtained SiOC/C hybrids delivered an excellent reversible capacity (926.8 mAh−1 at 0.2 A g−1), long cyclability (a capacity retention of 96.8%, after 600 cycles at 1.0 A g−1), and extraordinary rate performance (479.2 mAh g−1 at 5 A g−1). The marvelous electrochemical performance can be attributed to the compact connection of high conductivity carbon and microsphere SiOC, which not only enhances kinetics of ions and electrons during cycling but also improves the volume energy density. [ABSTRACT FROM AUTHOR]

A MoC/C composite material was conveniently synthesized via self-polymerization and pyrolysis. MoC nanoparticles are evenly distributed upon the carbon matrix and feature a cross-linked structure that can efficiently restrain the aggregation of MoC nanoparticles and relieve the volume alteration during the charging/discharging process. Moreover, the carbon material highly improved conductivity and reduced charge transfer resistance of the MoC/C-based electrode; this ensured its long-term stability with superior reversible capacity. At a current density of 1 A g−1, the MoC/C electrode delivered a reversible specific capacity of 550 mAh g−1 even after 500 cycles, demonstrating excellent electrochemical performance. This MoC-based electrode with an ultralong life cycle could be utilized as an anode material for next-generation lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Porous carbon powders are prepared from raw material camellia oleifera shells by ball milling and pyrolysis processes. Poly(vinylidene fluoride-hexafluoropropylene) (P(VDF-HFP)-based gel polymer electrolytes (GPEs) doped with different proportions of porous carbon powders are successfully fabricated using a classical inverse phase method, which is confirmed by X-ray diffraction, thermo-gravimetric analysis, and field emission scanning electron microscope. The results show that the porous GPE-3 membrane has a high liquid uptake ratio of about 104.3%, a high decomposition temperature of 435 °C, a rapidly stabilized interface impedance to 517.6 Ω after 5 days storage time, and a high ionic conductivity of 3.921 mS cm−1 at room temperature when the doping amount of porous carbon powders is 3.0 wt%. Furthermore, the assembled LiCoO2/GPE-3/Li coin cells can deliver a high initial discharge specific capacity of 152.7 mAh g−1 and an excellent initial coulombic efficiency of 97.27% at 0.1 C. These good properties indicate that the as-prepared GPE-3 can be used as a potential polymer electrolyte for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Nitrogen and sulfur co-doped porous nanocarbon (ZIF-C-N-S) catalyst was successfully synthesized derived from ZIF-8 and thiourea precursors. The electrochemical measurements indicate that the as-obtained ZIF-C-N-S catalyst exhibits higher electrocatalytic activity for oxygen reduction reaction (ORR) in alkaline electrolyte and superior durability-longer than commercial Pt/C catalyst. The enhancment of electrocatalytic activity mainly be come from the open pore structure, large specific surface area as well as the synergistic effect resulted from the co-doping of N and S atoms. In addition, the ZIF-C-N-S catalyst is also used as the air cathode catalyst in the microbial fuel cell (MFC) device. The maximum power density and stable output voltage of ZIF-C-N-S based MFC are 1315 mW/m2 and 0.48 V, respectively, which is better than that of Pt/C based MFC. [ABSTRACT FROM AUTHOR]

A hierarchically meso/macroporous phosphotungstic acid/TiO2 (HPW/TiO2) composite has been synthesized and introduced into the photoanode of dye-sensitized solar cells (DSSCs). The performance of the cell with hierarchically HPW/TiO2 modified photoanode was enhanced compared to the pristine P25 cell. When the mass percentage of HPW/TiO2 is 15 wt% in the photoanode, an increase of 28.2% improvement in the conversion efficiency are obtained. The interfacial layer modified by HPW can retard the recombination of electrons and broad the absorption to the visible region; the introduction of hierarchically porous structure in the photoanode can increase light scattering and dye adsorption. All these merits are responsible for an efficient enhancement in energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Background: Conventional endoscopy and endoscopic ultrasonography (EUS) are used to estimate the invasion depth of early-stage gastric cancers (EGCs), but estimates made by either technique are often inaccurate. We developed a model to determine the invasion depth of EGCs using conventional endoscopy and EUS findings, with pathology results as the reference.Methods: We performed a retrospective study of 195 patients (205 lesions) diagnosed with gastric cancers who underwent endoscopy and EUS followed by resection. Based on pathology analyses, lesions (n = 205) were assigned to categories of: mucosa invasion or minute invasion into the submucosal layer less than 500 μm from the muscularis mucosae (M-SM1) or penetration of 500 μm or more (≥SM2). The lesions were randomly assigned to derivation (138 lesions) and validation sets (67 lesions). A depth predictive model was proposed in the derivation set using multivariate logistic regression analyses. The discriminative power of this model was assessed in both sets.Results: Remarkable redness (OR 5.42; 95% CI 1.32-22.29), abrupt cutting of converging folds (OR 8.58; 95% CI 1.65-44.72), lesions location in the upper third of the stomach (OR 10.26; 95% CI 2.19-48.09), and deep invasion based on EUS findings (OR 16.53; 95% CI 4.48-61.15) significantly associated with ≥SM2 invasion. A model that incorporated these 4 variables discriminated between M-SM1 and ≥SM2 lesions with the area under the ROC curve of 0.865 in the derivation set and 0.797 in the validation set. In the derivation set, a cut-off score of 8 identified lesions as ≥SM2 with 54% sensitivity and 97% specificity. The model correctly predicted the invasion depth 89.86% of lesions; it overestimated the depth of 2.17% of lesions.Conclusions: We developed a model to identify EGCs with invasion depth ≥SM2 based on endoscopy and EUS findings. This model might reduce overestimation of gastric tumor depth and prevent unnecessary gastrectomy. [ABSTRACT FROM AUTHOR]

A novel flexible photoanode based on a silver nanowire (AgNW)/polymer composite electrode was fabricated and used for dye-sensitized solar cells. The AgNW/polymer composite substrate comprised a thin percolation network of AgNWs embedded on the surface of polyacrylic ester. As titanium dioxide film formed on top of the composite substrate, the effect of compression was investigated. Drop-cast sensitization was then used for both pressed and nonpressed photoanode, and the nonpressed one performed better. A cell efficiency of 0.91% was achieved under 100 mW cm simulated solar irradiation. After a bending test on the flexible photoanode, the solar cell retained 0.71% efficiency. [ABSTRACT FROM AUTHOR]

The silicon/graphite (Si/G) composite was prepared using pyrolytic polyacrylonitrile (PAN) as carbon precursor, which is a nitrogen-doped carbon that provides efficient pathway for electron transfer. The combination of flake graphite and pyrolytic carbon layer accommodates the large volume expansion of Si during discharge-charge process. The Si/G composite was synthesized via cost-effective liquid solidification followed by carbonization process. The effect of PAN content on electrochemical performance of composites was investigated. The composite containing 40 wt% PAN exhibits a relatively better rate capability and cycle performance than others. It exhibits initial reversible specific capacity of 793.6 mAh g at a current density of 100 mA g. High capacity of 661 mAh g can be reached after 50 cycles at current density of 500 mA g. [ABSTRACT FROM AUTHOR]

This study reports the improved performance of quantum dot-sensitized solar cells by inserting ZnS layer between the TiO film and CdS/CdSe quantum dots. An energy conversion efficiency of 2.84 % was attained. The enhancement introduced by inserting ZnS in moderation was attributed to the promoted nucleation of CdS QDs and enhanced light harvesting, as well as the improved electron transport at the interface in the photoanode. [ABSTRACT FROM AUTHOR]

The novel anode material for lithium-ion batteries, silicon-oxygen-carbon (Si-O-C) composite, is prepared by a liquid solidification combined with following pyrolysis process, in which silicon dioxide (SiO) is used as an additive agent to enhance the electrochemical performance of the composite. While the structure of the composite is confirmed by X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR), the morphology and microstructure were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. SEM and TEM observations reveal that the Si-O-C powders are about 1 μm in diameter, and there is a homogenous pyrolyzed carbon layer about 5 nm thick on the surface of the particle. The Si-O-C sample as anode material can deliver a high initial charge capacity of 753.4 mAh g, and the capacity keeps above 500.0 mAh g after 40 cycles at 100.0 mA g. The electrochemical impedance spectroscopy results show that the composite exhibits lower charge transfer resistance and higher lithium-ion diffusion rate compared with the Si-C anode, which indicates that the composite Si-O-C could be used as a promising anode material for lithium-ion batteries. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Mesoporous silica-zirconia supported phosphotungstic acid was synthesized by evaporation induced self-assembly method and used as oxidative desulfurization catalysts. The structural properties of as-prepared catalysts were characterized using various analytical techniques including X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, and nitrogen adsorption desorption. The experimental results showed that HPW was highly dispersed on mesoporous framework. The surface acidity of catalysts was analyzed by FTIR measurement of adsorbed pyridine.The surface Lewis acidity was improved with increasing the content of zirconium in the samples. The mesoporous composites were used as catalysts with HO as oxidant for oxidative desulfurization of model fuel. The catalytic activity results showed that the surface Lewis acid sites acted as selective adsorption active sites for dibenzothiophene, which facilitated the sulfur removal from model fuel in the presence of arene. A slight decrease in activity of the recovered catalyst used in the proceeding rounds indicated the reusability of the catalyst. [ABSTRACT FROM AUTHOR]

A series of mesoporous phosphotungstic acid/alumina composites (HPW/AlO) with various HPW contents were synthesized by evaporation-induced self-assembly method. These composites were characterized by nitrogen adsorption-desorption, TEM, FTIR, and UV-vis, and were tested as catalysts in oxidation desulfurization of model fuel composed of dibenzothiophene (DBT) and hydrocarbon, using HO as the oxidant. These composites exhibited high activity in catalytic oxidation of DBT in model fuel and good reusing ability. The best performance was achieved by using the mesoporous HPW/AlO with 15wt% HPW content, which resulted in a DBT conversion of 98% after 2 h reaction at 343 K, and it did not show significant activity degradation after 3 recycles. Characterization results showed that the mesoporous structure of alumina and the Keggin structure of HPW were preserved in the formed composite. These results suggested that HPW/AlO could be a promising catalyst in oxidative desulfurization process. [ABSTRACT FROM AUTHOR]

Two kinds of mesoporous phosphotungstic acid/SiO (HPW/SiO) have been synthesized by amino-functionalized (AF) method and evaporation-induced self-assembly (EISA) method, and their catalytic performance was investigated for deep oxidative desulfurization of benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) in diesel oil. Various analysis techniques such as XRD, TEM, N adsorption/desorption isotherms, FT-IR and P MAS NMR spectra have been used to investigate the pore structure and chemical properties of the resultant catalysts. The structural and spectroscopic analysis indicates both catalysts have a highly ordered 2D hexagonal mesostructure. HPW/SiO-EISA can maintain the Keggin structure of HPW molecules and has a high BET surface area (403 m/g). But in the AF method, the mesostructure of SBA-15 are partially blocked after the introduction of HPW molecules, and the Keggin structure of HPW molecules has been damaged. The catalytic performance results also show that HPW/SiO-EISA exhibits higher catalytic activity and stability compared to HPW/SiO-AF. As for HPW/SiO-EISA, the conversions of DBT, 4,6-DMDBT and BT are found to be 99.6, 97.6, 94.8 %, respectively. It shows a good maintenance of activity even after the 7th cycle of use. While corresponding conversions by using HPW/SiO-AF are found to be 90.2, 89.1 and 87.6 %, and the DBT conversion decreases to 75.7 % after the 5th cycle of use. [ABSTRACT FROM AUTHOR]

A novel mesoporous HPMo/SiO2 composite was synthesized by the sol-gel method with triblock copolymer EO20PO70EO20 as template. The properties of the product were characterized by X-ray diffraction, transmission electron microscopy, N2 adsorption-desorption isotherms, Fourier transform infrared spectrometer and inductively-coupled plasma analysis. The experimental results show that the product has a very ordered hexagonal mesostructure, and the HPMo is immobilized into the framework of silica. The final mesoporous composite shows excellent stability in polar solvents. Results of catalytic tests indicate that the composite is an effective catalyst for oxidation of dibenzothiophen, and there are few activity losses even after the third cycle of uses. The high catalytic activity and good insolubility make it a promising catalyst in oxidative desulfurization process. [ABSTRACT FROM AUTHOR]

Heteropoly acid of Keggin structure phosphotungstic(HPW) and phosphomolybdic(HPMo) were chemically anchored to the modified SBA-15 channel. The materials were used as catalyst for oxidative desulfurization of organic sulfur compounds including benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethydibenzothiophene (4,6-DMDBT). The experimental results show that the catalysts are efficient and reusable, the catalytic activity is hardly reduced even in the 5th cycle of use. [ABSTRACT FROM AUTHOR]

This paper extends existing commodity valuation models to allow for stochastic volatility and simultaneous jumps in the spot price and spot volatility. Closed-form valuation formulas for forwards, futures, futures options, geometric Asian options and commodity-linked bonds are obtained using the Heston (1993) and Bakshi and Madan (2000) methodology. Stochastic volatility and jumps do not affect the futures price at a given point in time. However, numerical examples indicate that they play important roles in pricing options on futures. [ABSTRACT FROM AUTHOR]

Copper nanowires (CuNWs) are used to prepare flexible, transparent conducting substrates due to their low cost and ease of fabrication on a large area. A CuNW/polymer composite substrate was prepared and vulcanized to create a novel flexible nano-Cu2S/polymer composite substrate. The physical and photovoltaic properties of the substrate can be controlled by tuning the concentration of CuNW dispersion during the preparation of CuNWs and nano Cu2S films. The nano-Cu2S-based composite substrate was used as an effective flexible counter electrode of a quantum-dot-sensitized solar cell (QDSSC) and resulted in a maximum cell efficiency of 1.01%. [ABSTRACT FROM AUTHOR]