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Continuum modelling of fluid-particle multiphase flows is often challenging when the solid phase becomes dense. In this work, a micro-macro approach combining the microscale discrete element method and the averaging method is used to explore the normal stress (pressure) of the solid phase to better describe dense fluid-particle flows. Various effects of Young's modulus, Poisson ratio, sliding friction, and rolling friction are examined and an exponential relationship between pressure and solid volume fraction is proposed. With this relationship implemented, the Two-Fluid Model can reproduce the steady discharge of particles from hoppers, which is regarded as a critical test of dense particle flow for TFM. The generality of the model is tested in a variety of cases, such as different hopper angles, orifice widths and fill heights. Comparisons of the present model with previous models are also made to enhance the understandings of fluid-particle multiphase flows. [Display omitted] • DEM and averaging method are used to retrieve a micro-macro relationship. • The relationship accounts for Young's modulus, Poisson ratio and friction. • TFM model incorporating the proposed relationship is validated in hoppers. • Accurately predicting solid pressure is important in dense fluid-particle flows. [ABSTRACT FROM AUTHOR]

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This study aimed to explore associations between semen quality and trace element level in serum and seminal plasma in Yorkshire boars. Semen quality of 112 Yorkshire boars was assessed for 13 weeks to calculate semen utilization rate, which was then divided into three categories: low utilization rate group (LG, < 60% utilization rate), medium utilization rate group (MG, 60–80%), and high utilization rate group (HG, > 80%). After grouping, serum and seminal plasma samples of selected boars were collected to determine concentrations of 10 elements including Ca, Mg, Cu, Fe, Zn, Mn, Se, Cr, Pb and Cd using inductively coupled plasma mass spectrometry. Results showed the increase of semen utilization rate was accompanied by the increase of sperm motility and the decrease of abnormal sperm rate among three groups (P < 0.01). Serum Fe concentration in LG boars was lower than that in HG boars (P < 0.05). Regression analysis revealed serum Fe concentration was positively correlated with sperm motility (r = 0.251; P < 0.05), while negatively correlated with abnormal sperm rate (r = −0.207; P < 0.05). However, MG and HG boars had lower serum Se concentration than LG boars (P < 0.05), and serum Se concentration contribution to sperm motility varied in a quadratic manner (Sperm motility = −0.0004 Se (serum) 2 +0.136 Se+74.06; r = 0.300; P < 0.01). Semen utilization rate tended to decrease with the increase of seminal plasma Pb concentration (P = 0.09). Regression analysis exhibited seminal plasma Pb negatively related to sperm motility (r = −0.237; P < 0.05), while positively correlated with abnormal sperm rate (r = 0.237; P < 0.05). Furthermore, seminal plasma Pb was the most influential factor among trace element in serum and seminal plasma on sperm motility basing on the generalized linear model analysis (P < 0.05). Sperm motility decreased by approximately 3.47% when seminal plasma Pb concentration increased from 0 μg/L to 11.16 μg/L. In conclusion, deficiency of serum Fe reduces semen utilization rate by impairing sperm motility and morphology, whereas excessive serum Se decreases sperm motility. More importantly, the mere existence of seminal plasma Pb has more impact on semen quality than other trace elements in serum and seminal plasma in Yorkshire boars. • Relationship between serum and seminal plasma elements and semen traits is different among boar breeds. • Deficiency of serum iron or excess of serum selenium Se decreases semen quality. • The presence of Pb in seminal plasma does harmful to sperm motility and morphology. • Semen quality is more sensitive to toxic elements than nutritional trace elements. [ABSTRACT FROM AUTHOR]

Doping in organic–inorganic perovskite semiconductors is an effective method to tailor their optoelectronic properties. In this work, manganese-doped perovskite films with different Mn/Pb ratios ranging from 0% to 2% were systematically studied. The device performance of 0.2% Mn-doped devices was improved compared to that of a device without Mn. However, a further increase of the doping concentration induced a decrease in performance. Several characteristics (especially different scanning probe microscopy characteristics) reveal that an increased dopant concentration results in reduced crystallinity and a change in the film morphology and causes a deterioration in photovoltaic performance for higher dopant concentrations. In the best-performing samples (0.2%), a shift in the valence band level and band gap are found which are responsible for the increased open circuit voltage, while increased grain boundaries and lower surface charge density are responsible for a small reduction in the short circuit current. Thus, multifunctional scanning probe microscopy approaches, combined with different film characterization techniques, offer us effective tools to investigate the impact of doping in the perovskite materials and the corresponding device performance. • Scanning Kelvin Probe Microscopy is used to test the open circuit voltage of films. • Conductive atomic force microscopy is used to study the short-circuit of films. • Electrostatic force microscopy is used to distinguish the surface charge change of films. [ABSTRACT FROM AUTHOR]

Synchronizing bus arrival and departure times at transfer stations could reduce excess transfer times. This paper addresses the planning level of bus schedule coordination problem through small timetable modifications to given an initial timetable. Timetable modifications consist of shifts in initial departure times of vehicles from the depot. Headway-sensitive passenger demand is also considered in this problem. A nonlinear mixed integer-programming model is proposed for the problem to maximize the number of total transferring passengers with smalll excess transfer times. Based on the analysis of the proposed model, a genetic algorithm combining local search (GACLS) is designed to solve this model. Several numerical experiments are performed to show the utility and performance of GACLS. For small case, the proposed GACLS is highly effective, and can obtain the optimal solution with less time than enumeration method. For large real case, the GACLS also has good performances. [ABSTRACT FROM AUTHOR]

Given a knowledge graph and a fact (a triple statement), fact checking is to decide whether the fact belongs to the missing part of the graph. Facts in real-world knowledge bases are typically interpreted by both topological and semantic context that is not fully exploited by existing methods. This paper introduces a novel fact checking method that explicitly exploits discriminant subgraph structures. Our method discovers discriminant subgraphs associated with a set of training facts, characterized by a class of graph fact checking rules. These rules incorporate expressive subgraph patterns to jointly describe both topological and ontological constraints. (1) We extend graph fact checking rules (GFCs) to a class of ontological graph fact checking rules (OGFCs). OGFCs generalize GFCs by incorporating both topological constraints and ontological closeness to best distinguish between true and false fact statements. We provide quality measures to characterize useful patterns that are both discriminant and diversified. (2) Despite the increased expressiveness, we show that it is feasible to discover OGFCs in large graphs with ontologies, by developing a supervised pattern discovery algorithm. To find useful OGFCs as early as possible, it generates subgraph patterns relevant to training facts and dynamically selects patterns from a pattern stream with a small update cost per pattern. We verify that OGFCs can be used as rules and provide useful features for other statistical learning-based fact checking models. Using real-world knowledge bases, we experimentally verify the efficiency and the effectiveness of OGFC-based techniques for fact checking. [ABSTRACT FROM AUTHOR]

Social support and self-esteem have been associated with depression in ASD caregivers. However, the mechanism of action and the self-esteem status of Chinese ASD caregivers have not been revealed. This study was designed to examine the potential paths among self-esteem, social support, and depression. In addition, we examined the self-esteem status of ASD caregivers in China. A total of 6120 participants were recruited via an online survey in China in this cross-sectional study. Caregivers younger than 60 years old and with an autistic child/children aged between 0 and 18 years were eligible for the study. The Sobel-Goodman mediation (SGM) test was performed to investigate the mediating effect of self-esteem between social support and depression. The indirect effect was statistically significant (β = −0.128, p = 0.049). The proportion of the total effect mediated by self-esteem was 24.6 %. Low self-esteem was observed in 60.64 % of the study participants, and 55.51 b% scored high in depression. A large percentage of study participants scored high in depression (56.89 %) and scored low in self-esteem (61.30 %) when not receiving any social support. The findings suggest a significant mediating effect of self-esteem on the association between social support and depression, indicating that receiving more social support decreases the depression level by increasing the ASD caregivers' self-esteem. • Self-esteem mediates the association between social support and depression. • In China, 60.64 % of the individual caring for autistic children scored low in self-esteem. • More than half (55.51 %) of the Chinese caregivers with autistic children reported high depression score. [ABSTRACT FROM AUTHOR]

Molecularly Tailored Surface Defect Modifier for Efficient and Stable Perovskite Solar Cells (Adv. Funct. Keywords: efficient and stable perovskite solar cells; large area; surface defect modifications EN efficient and stable perovskite solar cells large area surface defect modifications 1 1 1 09/15/23 20230912 NES 230912 B Surface Defect Modifications b In article number 2302404, Hongwei Zhu, Zhongjin Shen, Junfeng Wang, Michael Grätzel, and co-workers develop a novel surface passivator as the interfacial layer between the perovskite and hole transport layer to modify the surface defect states, yielding greatly improved photovoltaic performance and device stability. Efficient and stable perovskite solar cells, large area, surface defect modifications. [Extracted from the article]

Among various kinds of materials to substitute indium-tin-oxide (ITO) in rigid or flexible solar cells, oxide–metal–oxide (OMO) is one of the most promising. In this work, by means of reactive plasma deposition, a new combination of OMO structures, WO3/Ag/SnO2 (WAS), was deposited in one pot and each film thickness optimized to obtain high transmittance from 400 nm to 850 nm in wavelength and low sheet resistance, as well as mechanical robustness. The typical perovskite solar cells (PSCs) based on bare WAS composite film show poor device performance. Hence, aqueous soluble SnO2 nanoparticles were applied to modulate the band level mismatch at the interface between the WAS and MAPbI3 layers and the best-performing device with 14% conversion efficiency was achieved, which is the highest value reported hitherto with OMO structures as transparent conductive electrodes in PSCs. The results from various characterizations verify the interface engineering effect of the SnO2 nanoparticles. The unencapsulated WAS-based device stability also is comparable to that of the ITO-based device in continuous light exposure in ambient atmosphere (37% RH and 60 °C). This work reveals a great potential of OMO in place of ITO in solar cells while it still needs more attention and efforts in continuing development. [ABSTRACT FROM AUTHOR]