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With the advancement of society and the improvement of living standards, the significance of students' physical health has become increasingly prominent. However, currently, the assessment and analysis of students' physical health heavily depend on conventional statistical methods. Even with the application of data mining-related methodologies for analysis and evaluation, the exploitation and utilization of physical health big data remain relatively restricted. In this paper, an improved Canopy-K-means algorithm based on principal component analysis (PCA) is used to construct and analyze a portrait of students' physical fitness and health. The method combines data dimensionality reduction techniques and cluster analysis techniques, and its combined performance is the best compared to other algorithms in the ablation experiments for both male and female student data groups. In this paper, the algorithm was used to process the grouping of physical fitness test data of male and female students, realize the construction and analysis of students' physical fitness and health portrait, and give the exercise prescription for different categories of students. In this paper, the physical health test data of students of Yunnan Agricultural University in 2020–2022 were collected to carry out experiments, and the results found that there are differences in physical health status among students of different genders, grades, and majors in this university, and the physical health status of the students of Classes 2018 and 2019 is generally deficient; on different majors, the students of the Faculty of Agricultural Sciences are slightly superior to the Faculty of Science and Technology, and the students of the Faculty of Science and Technology are slightly superior to the students of the Faculty of Humanities and Social Sciences. Our study offers novel methods and ideas for the assessment and analysis of students' physical health, holding significant implications for schools and related departments in formulating scientific and effective physical education policies and health promotion strategies. [ABSTRACT FROM AUTHOR]

Due to the lack of direct assessment metrics, existing studies on the intensity of agricultural policies often utilize indicators such as Gross Domestic Product (GDP) of agriculture or the quantity of agricultural policies as measures. Optimizing methods for analyzing the intensity of agricultural policies will significantly impact parameter selection in agricultural policy research and the evaluation of policy effectiveness. In this study, we constructed a Chinese Agricultural Policy Corpus using agricultural policies released by various governmental agencies at the national level in China from 1982 to April 2023. We quantified the values of agricultural domain terms in the corpus and evaluated the intensity of each agricultural policy document. The validation results of this study indicate a strong correlation between the intensity of agricultural policies and agricultural GDP. The trend in agricultural GDP changes lags behind policy intensity by 2.5 years (at a 95% confidence level), thus validating the rationality of our constructed corpus, agricultural policy scoring dataset, and methodology. [ABSTRACT FROM AUTHOR]

Developing efficient materials and techniques to remove elemental mercury (Hg0) from anthropogenic sources is the key to fulfilling the Minamata Convention and freeing us from a Hg-polluted world. Functionalized substrate-supported metal chalcogenides have been found to be a group of effective sorbents for Hg0 capture from industrial sources in the past decade. However, there is still no work bridging previous achievements and future developments in related areas. This review thus categorized supported metal chalcogenides into six groups and systematically explored the preparation methods, properties, performance, and design logics of supported metal chalcogenides for Hg0 capture from anthropogenic sources. The supporting effects increase the exposure of metal chalcogenides, promote the diffusion of Hg0, combine different active components, improve the resistance to flue gas interference, and serve the recycling of both spent sorbents and mercury resources. Based on systematical discussions, future developmental prospects of supported metal chalcogenides are proposed, aiming to further refine the design logic of materials, develop more effective synthesis methods, and standardize the performance evaluation systems. The main purpose of this work is to guide future research on supported metal chalcogenides for Hg0 removal from anthropogenic sources in the post-Minamata era. [ABSTRACT FROM AUTHOR]

To develop a geological nuclear waste disposal facility from scratch, the hydro-mechanical properties of the host rock are fundamental for its initial construction, long-term system evolution, closure, and post-closure phases. In this paper, a transversely isotropic damage constitutive model was developed to describe the nonlinear behavior of clayey rock, based on the modified Drucker–Prager Cap model. Considering the self-sealing effect, a hydraulic conductivity evolution law of typical clayey rock was established based on in situ measurements. These theoretical models were further implemented in the finite element method software ABAQUS FEA (Finite Element Analysis) utilizing the subroutine USDFLD, which is a user subroutine to redefine field variables at a material point in ABAQUS. The hydro-mechanical response of an underground research laboratory during excavation and operation was reproduced by three-dimensional numerical simulation to validate the proposed models. The results highlighted that the developed theoretical model could efficiently reproduce the evolution of pore water pressure and deformation, compared to the in situ measurements in the excavation damaged/disturbed zone (EDZ) and hydraulic disturbed zone (HDZ) driven by tunnel excavation. Highlights: A damage constitutive model and a permeability evolution law are developed. Theoretical models are implemented in the software ABAQUS FEA. Hydro-mechanical responses of an underground research laboratory during excavation and operation are simulated. Comparison with the in-situ measurements highlights the theories' efficiency. [ABSTRACT FROM AUTHOR]

Taper end-mills are extensively employed in CNC machining and the flute is integral to the cutting efficacy of the end-mill. Nonetheless, forming the grinding wheel path for a taper end-mill is exceptionally challenging owing to its intricate structure and variable cross-section. In traditional methods, the wheel path is generated by experience, and the accuracy of flute parameters cannot be guaranteed. To overcome those problems, this paper proposed a wheel path generation approach for taper end-mills flute-grinding subject to variable cross-section, which is capable of ensuring the accuracy of parameters of the cross-section. In the wheel path generation, the taper end-mill is discretized into a series of finite slices, which can be transformed into solving a series sub-problem of grinding cylindrical end-mills. To eliminate the interference and discontinuity caused by the discretization, the enhancement based on sensitivity analysis and smoothing are used to optimize the grinding wheel path. Finally, the approach is validated by both simulation and experiments. The results indicated that this approach is capable of generating the wheel path for grinding the taper end-mill flute accurately and efficiently subject to the variable cross-section parameters. [ABSTRACT FROM AUTHOR]

Highlights: The Cu-doped graphitic carbon nitride (g-C3N4) material is synthesized by an in situ thermal polymerization strategy, through which the atomic dispersion and coordination structure of Cu on g-C3N4 are realized by regulating the doping level of Cu. High Faraday efficiency of CH4 of 49.04% and a maximum CH4/C2H4 ratio up to 35.03 are achieved for the first time on g-C3N4-supported Cu single-atom catalyst. Structure–activity relationship analysis based on experimental and theoretical studies demonstrates the well-defined Cu single atoms coordinated with N atoms in the nitrogen cavity of g-C3N4 are active sites for CO2-to-CH4. Electrochemical reduction of CO2 into high-value hydrocarbons and alcohols by using Cu-based catalysts is a promising and attractive technology for CO2 capture and utilization, resulting from their high catalytic activity and selectivity. The mobility and accessibility of active sites in Cu-based catalysts significantly hinder the development of efficient Cu-based catalysts for CO2 electrochemical reduction reaction (CO2RR). Herein, a facile and effective strategy is developed to engineer accessible and structural stable Cu sites by incorporating single atomic Cu into the nitrogen cavities of the host graphitic carbon nitride (g-C3N4) as the active sites for CO2-to-CH4 conversion in CO2RR. By regulating the coordination and density of Cu sites in g-C3N4, an optimal catalyst corresponding to a one Cu atom in one nitrogen cavity reaches the highest CH4 Faraday efficiency of 49.04% and produces the products with a high CH4/C2H4 ratio over 9. This work provides the first experimental study on g-C3N4-supported single Cu atom catalyst for efficient CH4 production from CO2RR and suggests a principle in designing highly stable and selective high-efficiency Cu-based catalysts for CO2RR by engineering Cu active sites in 2D materials with porous crystal structures. [ABSTRACT FROM AUTHOR]

Flanks of end mills are prone to wear in a long machining process. Regrinding is widely used in workshops to restore the flank to an original-like state. However, the traditional method involves material waste by trial and error and dramatically decreases the potential regrinding. Moreover, over-cut would happen to the flutes of worn cutters in the regrinding processes because of improper wheel path. This study presented a new approach to planning the wheel path for regrinding worn end mills to minimize material loss and recover the over-cut. In planning, a scaling method was developed to determine the maximum size of the new cutter according to the similarity of cutter shapes before and after regrinding. Then, the wheel path is first generated by envelope theory to regrind the worn area with a four-axis computer numerical control grinder according to the new size of cutters. Moreover, a second regrinding strategy is applied to recover the flute shape over-cut in the first grinding. Finally, the proposed method is verified by an experiment. Results showed that the proposed approach could save 25% of cutter material compared with the traditional method and ensure at least three regrinding times. This work effectively provides a general regrinding solution for the worn flank with maximum material-saving and regrinding period. [ABSTRACT FROM AUTHOR]

Jianke Yang, Yehui Wu, Yadong Li, Rujia Li, and Jiaojiao Chen have contributed equally to this work.The Journal of Supercomputinghttps://doi.org/10.1007/s11227-024-06091-zIn this article Jianke Yang should have been denoted as an equally contributing author instead of Jianping Yang.The original article has been corrected.Publisher's NoteSpringer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.By Rongbiao Ji; Jianke Yang; Yehui Wu; Yadong Li; Rujia Li; Jiaojiao Chen and Jianping YangReported by Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

The degradation of components resulted from wear is unavoidable in service, which could be partly solved by applying surface treatment technique. Stellite-6 cobalt-based alloy is considered as a potential cladding material to improve the wear resistance of base materials owing to its excellent hardness and strength. The microstructural evolution and local mechanical properties of Co-rich matrix and Cr-rich eutectic carbide of Stellite-6 cladding with different aging times at 900 °C are investigated by optical microscopy, field emission scanning electron microscope and nanoindentation testing. The tribological characteristics of the matrix and eutectic carbide itself are systematically investigated using the single-pass nano-scratch testing. In the matrix region, the carbide precipitations occur after 5 h and coarsens after 10 h aging. The nanoindentation results indicate that the hardness of the matrix regions is significantly increased due to the presence of dispersed carbide and fine stripe-like precipitations. The nano-scratch tests depict that the wear resistance is improved with higher matrix hardness to support eutectic carbide based on aging treatment. Potential improvement on tribological performance through the aging treatment procedure is proved based on the micromechanical and wear behaviors of matrix and eutectic carbide were identified. [ABSTRACT FROM AUTHOR]

Highly efficient dewatering is essential to the reduction and reclamation disposal of oily sludge, which is a waste from the extraction, transportation, and refining of crude oil. How to effectively break the water/oil emulsion is a paramount challenge for dewatering of oily sludge. In this work, a Fenton oxidation approach was adopted for the dewatering of oily sludge. The results show that the oxidizing free radicals originated from Fenton agent effectively tailored the native petroleum hydrocarbon compounds into smaller organic molecules, hence destructing the colloidal structure of oily sludge and decreasing the viscosity as well. Meanwhile, the zeta potential of oily sludge was increased, implying the decrease of repulsive electrostatic force to realize easy coalescence of water droplets. Thus, the steric and electrostatic barriers which restrained the coalescence of dispersed water droplets in water/oil emulsion were removed. With these advantages, the Fenton oxidation approach derived the significant decrease of water content, in which 0.294 kg water was removed from per kilogram oily sludge under the optimal operation condition (i.e., pH value of 3, solid–liquid ratio of 1:10, Fe2+ concentration of 0.4 g/L and H2O2/Fe2+ ratio of 10:1, and reaction temperature of 50 °C). In addition, the quality of oil phase was upgraded after Fenton oxidation treatment accompanying with the degradation of native organic substances in oily sludge, and the heating value of oily sludge was increased from 8680 to 9260 kJ·kg−1, which would facilitate to the subsequent thermal conversion like pyrolysis or incineration. Such results demonstrate that the Fenton oxidation approach is efficient for the dewatering as well as the upgrading of oily sludge. [ABSTRACT FROM AUTHOR]

Electrocatalysis of CO2 toward multicarbon (C2+) products have multifaceted applications in the energy and chemical industries, offers an attractive route to mitigate carbon emissions and abate the depletion of fossil fuels. However, the productivity of CO2-to-C2+ products suffers from a low selectivity and reaction rate owing to the difficulty in C-C coupling and the multiple electron-proton transfer steps. Recently, numerous tandem catalysts have been developed to improve the selectivity and formation rate of CO2-to-C2+ products via coupled multiple reaction steps, exhibiting high industrial practicability. This review summarized recent progresses in the formation of C2+ products from CO2 electrolysis on tandem catalysts. In this review, we highlight the cooperative regulation strategy of tandem catalysts formed by introducing different types of new components and reveal the relationships between *CO intermediate mass transport and the selectivity of C2+ products. Moreover, theoretical insight into the tandem catalytic mechanisms underlying the enhanced C2+ selectivity is also provided. Finally, the remaining challenges and opportunities for the electrocatalytic CO2 toward C2+ products are discussed. [ABSTRACT FROM AUTHOR]

An understanding of the creep behavior of clayey rocks is considered fundamental for further development in the fields of nuclear waste underground disposal, underground mine design, strata control, and many other geological phenomena occurring in the earth's crust. In this research, we performed a series of long-term triaxial compressive tests on a typical clayey rock, which confirmed its high creep potential beyond the creep threshold. Further analysis of the creep mechanism of this clayey rock indicated that two effects—strengthening and damage—are accompanied by the creep process. Additionally, based on the overstress theory and Drucker–Prager cap model, we developed a novel constitutive model considering two creep reference surfaces—cohesion and consolidation. Meanwhile, laws to reflect the strength and damage effect during creep were established and applied to the above constitutive model. Finally, the above theoretical studies were implemented in the finite element method software ABAQUS FEA using the subroutines CREEP and USDFLD. Some theory parameters were verified through back analysis. A comparison between the experimental results and numerical simulations confirmed the superiority of the established theoretical model. Highlights: Clayey rock exhibits high creep potential beyond the creep threshold. Two effects—strengthening and damage—are accompanied by the creep process. A novel creep constitutive model was established. Strengthening and damage laws during creep were developed. Model numerical implementation and parameters determination. [ABSTRACT FROM AUTHOR]

The formation mechanisms for two carbides with co-existence and increasing stacking faults nearby the carbides during surfacing welding were investigated in this study. The results indicated that the surfacing layer had a two-phase structure of a matrix phase and a second phase, the density of the second phase was relatively small and the second phase was discontinuous, by contrast with the as-received welding wire. Relatively uniform microstructure of surfacing layer and the welding interface without melting of base metal were obtained, resulting in an inapparent change in the microhardness. A few carbides with blocky shape were identified in the surfacing layer. The mechanisms for (Cr,Co)23C6 of face-centered cubic crystal structure co-existing with (Cr,Co)7C3 of hexagonal close-packed crystal structure and (Cr,Co)23C6 subsequently forming close to the pre-formed (Cr,Co)7C3 during the cooling process were discussed in alloying element, calculated equilibrium phase diagram, Gibbs energy, etc. The relatively higher density of the stacking fault present around the carbides was understood from forming energy of stacking faults. [ABSTRACT FROM AUTHOR]

Phenomenons of adhesive contact are quite common in micro-electro-mechanical system devices, whose reliability is severely affected by the adhesive properties of contacting bodies. The Classical JKR model fails when the contacting body size decreases to nanoscale because of the assumption failures. This investigation reports a novel numerical model of adhesive contact between a rigid smooth sphere and an elastic multi-layered medium, in which the Hamaker summation method and Lennard–Jones intermolecular potential law are employed. Analytical expressions of adhesive contact pressure for multi-layered media are derived. The Newton–Raphson method and fast Fourier transform algorithm are introduced to enhance the computational efficiency. Further, the effectiveness of the present model is validated by comparison with results from published literature. Finally, parametric studies about the influences of layer properties, like elastic modulus, Dupré adhesion energy and layer thickness, on the adhesive mechanical behavior of multi-layered media are carried out. The analysis results are beneficial to the optimal design of an adhesive contact system to improve its comprehensive mechanical performance. [ABSTRACT FROM AUTHOR]

For addressing the Allis-type anomalies, a fractional degree reference dependent stochastic dominance rule is developed which is a generalization of the integer degree reference dependent stochastic dominance rules. This new rule can effectively explain why the risk comparison does not satisfy translational invariance and scaling invariance in some cases. The rule also has a good property that it is compatible with the endowment effect of risk. This rule can help risk-averse but not absolute risk-averse decision makers to compare risks relative to reference points. We present some tractable equivalent integral conditions for the fractional degree reference dependent stochastic dominance rule, as well as some practical applications for the rule in economics and finance. [ABSTRACT FROM AUTHOR]

Predicting the mechanical behaviors of tunnel and subsurface facilities is an effective way to prevent accidental disasters. However, some drawbacks exist in many traditional prediction models, such as inadequate consideration of impacting factors, low predictive accuracy, and high computational cost. To this end, a coupled model based on deep attention-based temporal convolutional network (DATCN) is proposed for multiple prediction of structural mechanical behavior, where temporal convolutional network and self-attention mechanism are applied to learn temporal dependencies and spatial dependencies respectively. Subsequently, the DATCN model is formalized on a long-term dataset collected using a Structural Health Monitoring System in the Wuhan Yangtze River tunnel. Using three evaluation indicators, a series of data experiments are conducted to obtain the most appropriate parameters involved in the model and the superiority of DATCN over other commonly used models including LSTM, RNN, GRU, LR, and SVR is discussed. Experimental results indicate that future structural behavior shows a strong correlation between spatial dependencies and historical performance, especially that in the last 16 days. Moreover, the predictive capability of DATCN is the best compared to other commonly used models, whose predictive accuracy for the next 10 days is better than 88% and improved by 1.726% at least. Finally, the DATCN model is adopted to predict the structural behavior of the tunnel under extreme conditions as a field application, and the results suggest that the DATCN model is robust and accurate. [ABSTRACT FROM AUTHOR]

Atrioventricular septal defects (AVSD) are a complicated subtype of congenital heart defects for which the genetic basis is poorly understood. Many studies have demonstrated that the transcription factor SOX7 plays a pivotal role in cardiovascular development. However, whether SOX7 single nucleotide variants are involved in AVSD pathogenesis is unclear. To explore the potential pathogenic role of SOX7 variants, we recruited a total of 100 sporadic non-syndromic AVSD Chinese Han patients and screened SOX7 variants in the patient cohort by targeted sequencing. Functional assays were performed to evaluate pathogenicity of nonsynonymous variants of SOX7. We identified three rare SOX7 variants, c.40C > G, c.542G > A, and c.743C > T, in the patient cohort, all of which were found to be highly conserved in mammals. Compared to the wild type, these SOX7 variants had increased mRNA expression and decreased protein expression. In developing hearts, SOX7 and GATA4 were highly expressed in the region of atrioventricular cushions. Moreover, SOX7 overexpression promoted the expression of GATA4 in human umbilical vein endothelial cells. A chromatin immunoprecipitation assay revealed that SOX7 could directly bind to the GATA4 promoter and luciferase assays demonstrated that SOX7 activated the GATA4 promoter. The SOX7 variants had impaired transcriptional activity relative to wild-type SOX7. Furthermore, the SOX7 variants altered the ability of GATA4 to regulate its target genes. In conclusion, our findings showed that deleterious SOX7 variants potentially contribute to human AVSD by impairing its interaction with GATA4. This study provides novel insights into the etiology of AVSD and contributes new strategies to the prenatal diagnosis of AVSD. [ABSTRACT FROM AUTHOR]

Highlights: Catalytically inert 2D Bi2O3 is activated for boosting electrochemical hydrogen evolution reaction (HER) via oxygen vacancy concentration modulation. The relationship between the varied oxygen vacancy concentrations and the corresponding HER activity is revealed by both experimental Vo verification and theoretical density-functional theory calculations. This work provides insights into activating catalytically inert materials into high-performance catalysts. Oxygen vacancies (Vo) in electrocatalysts are closely correlated with the hydrogen evolution reaction (HER) activity. The role of vacancy defects and the effect of their concentration, however, yet remains unclear. Herein, Bi2O3, an unfavorable electrocatalyst for the HER due to a less than ideal hydrogen adsorption Gibbs free energy (ΔGH*), is utilized as a perfect model to explore the function of Vo on HER performance. Through a facile plasma irradiation strategy, Bi2O3 nanosheets with different Vo concentrations are fabricated to evaluate the influence of defects on the HER process. Unexpectedly, while the generated oxygen vacancies contribute to the enhanced HER performance, higher Vo concentrations beyond a saturation value result in a significant drop in HER activity. By tunning the Vo concentration in the Bi2O3 nanosheets via adjusting the treatment time, the Bi2O3 catalyst with an optimized oxygen vacancy concentration and detectable charge carrier concentration of 1.52 × 1024 cm−3 demonstrates enhanced HER performance with an overpotential of 174.2 mV to reach 10 mA cm−2, a Tafel slope of 80 mV dec−1, and an exchange current density of 316 mA cm−2 in an alkaline solution, which approaches the top-tier activity among Bi-based HER electrocatalysts. Density-functional theory calculations confirm the preferred adsorption of H* onto Bi2O3 as a function of oxygen chemical potential (∆μO) and oxygen partial potential (PO2) and reveal that high Vo concentrations result in excessive stability of adsorbed hydrogen and hence the inferior HER activity. This study reveals the oxygen vacancy concentration-HER catalytic activity relationship and provides insights into activating catalytically inert materials into highly efficient electrocatalysts. [ABSTRACT FROM AUTHOR]

Desert plants evolve different photosynthetic organs to adapt to the extreme environment. We studied the leaf and canopy gas exchange, chlorophyll content, fluorescence parameters, and anatomical structure of different photosynthetic organs (leaf and assimilating stem) on four desert plants (Nitraria sphaerocarpa, Caragana korshinskii, Haloxylon ammodendron, and Calligonum mongolicum). The results showed a higher net photosynthetic rate (PN) in the assimilating stems of H. ammodendron and C. mongolicum, which also had a higher light saturation point and a lower light compensation point than leaves (N. sphaerocarpa and C. korshinskii), suggesting more efficient solar energy utilization in the former. Within each species, canopy apparent photosynthetic rate (CAP) was significantly lower than PN, and the daily average CAP of the assimilating stems was significantly higher than leaves. These findings indicated that the photosynthetic response of desert plants was specific to photosynthetic organs. We concluded that the assimilating stem was a superior adaption for desert plants to survive the arid environments. [ABSTRACT FROM AUTHOR]

Engineering pharmaceutical formulations is governed by a number of variables, and the finding of the optimal preparation is intricately linked to the exploration of a multiparametric space through a variety of optimization tasks. As a result, making such optimization activities simpler is a significant undertaking. For the purposes of this study, we suggested a prediction model that was based on least square support vector machine (LSSVM) and whose parameters were optimized using the particle swarm optimization algorithm (PSO-LSSVM model). Other in silico optimization methods were used and compared, including the LSSVM and the back propagation (BP) neural networks algorithm. PSO-LSSVM demonstrated the highest performance on the test dataset, with the lowest mean square error. In addition, two dosage forms, quercetin solid dispersion and apigenin nanoparticles, were selected as model formulations due to the wide range of formulation compositions and manufacturing factors used in their production. Three different models were used to predict the ideal formulations of two different dosage forms, and in real world, the Taguchi orthogonal design arrays were used to optimize the formulations of each dosage form. It is clear that the predicted performance of two formulations using PSO-LSSVM was both consistent with the outcomes of the Taguchi orthogonal planned experiment, demonstrating the model’s good reliability and high usefulness. Together, our PSO-LSSVM prediction model has the potential to accurately predict the best possible formulations, reduce the reliance on experimental effort, accelerate the process of formulation design, and provide a low-cost solution to drug preparation optimization. [ABSTRACT FROM AUTHOR]

A new type of internally illuminated honeycomb photoreactor was designed. The honeycomb catalyst prepared by using Ce-doped TiO2 with 1%–2% vanadium and tungsten was employed for mercury removal from simulated industrial flue gas. The adsorption kinetics in the reaction process were studied. The results showed that the internally illuminated honeycomb photoreactor had good mercury removal performance. When the temperature was 25°C and the ultraviolet (UV) light intensity reached 80 µW/cm2, the mercury removal efficiency reached 92.5%. The mercury removal efficiency increased significantly with the doping ratio of Ce. XPS analysis showed that the oxidation state of Ce changed from 4 to 3 in the mercury removal reaction and produced lattice oxygen, which acts as an oxidant. O2 can promote mercury removal by honeycomb catalysts; SO2 and HCl also had positive effects, while NO had an inhibitory effect on mercury removal. Kinetic research in the reaction process showed that the quasi-first-order dynamic model had good fitting results, and the correlation coefficients of the fitting results for multiple sets of experimental data were more than 0.999. [ABSTRACT FROM AUTHOR]

Accurate understanding of traffic signs is integral to driving safety. Questionnaires and behavior tests are usually used to measure sign comprehension. However, biometric indicators have also been developed to measure sign comprehension. This study investigated neural indicators underlying traffic sign understanding by measuring event-related potentials (ERPs). A stimulus 1–stimulus 2 paradigm was adopted. A sign identification experiment was conducted independently in a laboratory setting with 60 participants divided into two groups. ERPs and brain topographies were analyzed to evaluate traffic sign comprehension. Misunderstanding was associated with greater amplitudes of the N300 and N400. The study demonstrates that the N300 and N400 are effective neural indicators for evaluating sign comprehension and can be used for predicting drivers' sign comprehension and behavior. [ABSTRACT FROM AUTHOR]

Due to long-term water-flooding, thief zones have been formed in the Donghe sandstone reservoir in the Hade Oilfield, resulting in an inefficient water flooding cycle. The genetic mechanism and level of thief zones are defined based on the fine reservoir description using core data and dynamic data. For original reservoirs with large pore throats (generally larger than 5 μm), as the porosity and permeability rapidly increase with water injection, it is likely to form thief zones. And thief zones prone to form in the area where the interlayer flow barrier formed with horizontal occurrence. Based on the analysis of sedimentary facies, pore structure, flow barrier, production injection ratio, and water content, classification criteria for the thief zones are carried out. The location and characteristics of the severe, potential, and rudimentary thief zones were determined. The results indicate that the thief zones are primarily distributed in layers 1 and 2 and are mainly distributed in the central region. Verification using tracer data indicates that the coincidence rate is 95%, which proves the accuracy of thief zone identification and prediction. This work adds value aiding in the characterization and evaluation of the hydrocarbon reservoir. It provides a basis for oil production in the Hade Oilfield and may be potentially applicable to other regions to increase the hydrocarbon production. [ABSTRACT FROM AUTHOR]

Highlights: Synaptic devices that mimic synaptic functions are discussed by categorizing them into electrically stimulated, optically stimulated, and photoelectric synergetic synaptic devices based on stimulation of electrical and optical signals. The working mechanisms, progress, and application scenarios of synaptic devices based on electrical and optical signals are compared and analyzed. The performances and future development of various synaptic devices that could be significant for building efficient neuromorphic systems are prospected.Neuromorphic computing simulates the operation of biological brain function for information processing and can potentially solve the bottleneck of the von Neumann architecture. This computing is realized based on memristive hardware neural networks in which synaptic devices that mimic biological synapses of the brain are the primary units. Mimicking synaptic functions with these devices is critical in neuromorphic systems. In the last decade, electrical and optical signals have been incorporated into the synaptic devices and promoted the simulation of various synaptic functions. In this review, these devices are discussed by categorizing them into electrically stimulated, optically stimulated, and photoelectric synergetic synaptic devices based on stimulation of electrical and optical signals. The working mechanisms of the devices are analyzed in detail. This is followed by a discussion of the progress in mimicking synaptic functions. In addition, existing application scenarios of various synaptic devices are outlined. Furthermore, the performances and future development of the synaptic devices that could be significant for building efficient neuromorphic systems are prospected. [ABSTRACT FROM AUTHOR]

Objectives: It has been reported that occupational exposure to indium compounds, including indium-tin oxide, can induce pulmonary inflammation resulting in serious indium lung disease. However, whether there is an early effect of indium exposure on inflammatory factor expression remains unclear. Methods: Twenty indium-tin oxide processing workers and 15 healthy volunteers were recruited to measure serum indium levels, respiratory symptoms, pulmonary function, and serum inflammatory factor levels. Results: Although low serum indium was detected in workers, lung abnormalities were not increased, compared with healthy population. However, serum G-CSF, IL-4, IL-5, TNF-alpha, and TNF-beta levels were significantly increased, while IL-16 and TIMP-1 were obviously down-regulated in indium-tin oxide processing workers. These inflammatory factor levels showed a significant correlation with serum indium levels. Conclusions: Basing on our findings, we speculate that low serum indium levels may induce inflammatory responses, which may be an adaptive response or may cause lung diseases. Therefore, further experiments or follow-up is needed. However, better safeguard procedures and indium exposure reduction should be considered in ITO industry. [ABSTRACT FROM AUTHOR]

Purpose: TRAF4 plays an important role in the development and progression of breast cancer, but its impact on chemotherapy resistance is as yet, however, poorly understood. Methods: Western blotting, immunoprecipitation, and immunofluorescence staining were used to identify and verify that TRAF4 was a novel substrate of SIAH1 and prevented SIAH1-mediated β-catenin degradation. Cell proliferation analysis and Flow cytometry analysis were utilized to detect TRAF4′s function on the growth-inhibitory effect of etoposide. Immunohistochemistry was used to detect the expression of TRAF4, SIAH1, and β-catenin. Statistical analysis was used to analyze the relationships between them with clinical parameters and curative effect of chemotherapy pathologically. Results: Our results suggested that TRAF4 prevents SIAH1-mediated β-catenin degradation. TRAF4 was a novel substrate of SIAH1 and the TRAF domain of TRAF4 was critical for binding to SIAH1. TRAF4 reduced the growth-inhibitory effect of etoposide via reducing the number of S-phase cells and suppressing cell apoptosis. Concordantly, we found that breast cancer patients with a low-TRAF4 expression benefited most from chemotherapy, who had higher tumor volume reduction rate and better pathological response, while, the high-TRAF4 expression group had lower tumor volume reduction rate and poor pathological response. Conclusions: TRAF4 was a novel substrate of SIAH1 and prevented SIAH1-mediated β-catenin degradation, which explains the protective effect of TRAF4 on β-catenin during cell stress and links TRAF4 to chemotherapy resistance in tumors. These findings implicated a novel pathway for the oncogenic function of TRAF4. [ABSTRACT FROM AUTHOR]

Conotruncal heart defects (CTDs) are closely related to defective outflow tract (OFT) development, in which cardiac neural crest cells (CNCCs) play an indispensable role. However, the genetic etiology of CTDs remains unclear. Mesoderm posterior 2 (MESP2) is an important transcription factor regulating early cardiogenesis. Nevertheless, MESP2 variants have not been reported in congenital heart defect (CHD) patients. We first identified four MESP2 variants in 601 sporadic nonsyndromic CTD patients that were not detected in 400 healthy controls using targeted sequencing. Reverse transcription-quantitative PCR (RT-qPCR), immunohistochemistry, and immunofluorescence assays revealed MESP2 expression in the OFT of Carnegie stage (CS) 11, CS13, and CS15 human embryos and embryonic day (E) 8.5, E10, and E11.5 mouse embryos. Functional analyses in HEK 293T cells, HL-1 cells, JoMa1 cells, and primary mouse CNCCs revealed that MESP2 directly regulates the transcriptional activities of downstream CTD-related genes and promotes CNCC proliferation by regulating cell cycle factors. Three MESP2 variants, c.346G>C (p.G116R), c.921C>G (p.Y307X), and c.59A>T (p.Q20L), altered the transcriptional activities of MYOCD, GATA4, NKX2.5, and CFC1 and inhibited CNCC proliferation by upregulating p21cip1 or downregulating Cdk4. Based on our findings, MESP2 variants disrupted MESP2 function by interfering with CNCC proliferation during OFT development, which may contribute to CTDs. Key messages: This study first analyzed MESP2 variants identified in sporadic nonsyndromic CTD patients. MESP2 is expressed in the OFT of different stages of human and mouse embryos. MESP2 regulates the transcriptional activities of downstream CTD-related genes and promotes CNCC proliferation by regulating cell cycle factor p21cip1 or Cdk4. [ABSTRACT FROM AUTHOR]

Conical end-mills are widely used in CNC machining and the flank has a great influence on the performance of the end-mill. However, the complex structures of conical flank make it difficult to grind. The traditional method for conical flank grinding is to control the grinding wheel with a 3-axis archimedes helix motion, which cannot guarantee the accuracy of the desired flank parameters, i.e., relief angle and flank angle. To solve this problem, this paper proposed a wheel path generation method for 4-axis CNC conical flank grinding. In this model, the grinding processes were discretized into a finite of cylindrical end-mill grinding. For each cylindrical end-mill, the machined flank parameters could be calculated within the cross-section through the envelope theory. Additionally, the geometrical constraints to avoid interference and abnormal flank profile were developed based on the cylindrical end-mill. The wheel path was obtained by calculating the wheel's position and orientation for the discretized cylindrical end-mill section by section. Also, an integral procedure was built to optimize and simulate the conical flank grinding. The simulation results showed that the proposed method had a wide range of applications that could provide a general solution for the conical CNC flanking operations and also could be extended to grind the complex surface of end-mills in the future study. [ABSTRACT FROM AUTHOR]

The environmental ecology of the Yangtze River Economic Zone (YREZ) faces ecological function decline, deterioration and degradation under intense human activities, long-term development and utilization and its economy has developed rapidly over recent decades. Eco-efficiency is considered as a measure of coordinated development of economy, resources, environment and ecology, and is currently considered a very important issue. In this paper, based on the slack-based measure and data envelope analysis model, we take 129 prefecture-level cities of the YREZ as the study unit and measure the eco-efficiency of the YREZ in 2000, 2005, 2010 and 2015, which considers undesired output. The evaluation of the status quo of the regional eco-efficiency development was carried out at provincial, prefectural and city scales. The spatial autocorrelation test model and standard deviation ellipse were used to analyze the spatially distributed characteristics and the evolutionary regularity of eco-efficiency. Our study suggested that the eco-efficiency value varied significantly at different spatiotemporal scales and the overall distribution presented an "N-shaped" pattern, the value is the largest downstream and the smallest upstream. Regional eco-efficiency presented certain volatility in growth and a clear spatial positive agglomeration trend from 2000 to 2015. The spatial distribution of each agglomeration area was also significantly different, forming some high-high agglomeration areas at the center of the shaft with Shanghai and surrounding cities, and some low-low agglomeration areas at the center with middle reaches and upstream cities. The low-high over-aggregation and high-low polarization clusters were fewer. At the same time, with the change of the research period, the degree of positive agglomeration became increasingly pronounced and the eco-efficiency gap of the neighborhood unit reduced. The regional eco-efficiency value of the YREZ presented a spatial distribution pattern in the northeast-southwest axis and the evolutionary pattern of the regional eco-efficiency similarly showed a northeast-southwest orientation. [ABSTRACT FROM AUTHOR]

Reduction of mercury emission from coal combustion is a serious task for public health and environmental societies. Herein, Ce-doped TiO2 (Ce/TiO2) catalyst coupling with a novel optical fiber monolith reactor was applied to efficiently remove elemental mercury (Hg0) from coal-fired flue gas. Under the optimal operation condition (i.e., 1.5 mW/cm2 UV light, 90 °C), above 95% of Hg0 removal efficiency was attained over the optical fiber monolith reactor coating with 3.40 g/m2 Ce/TiO2 catalyst. The effects of flue gas compositions on Hg0 removal performance were clarified systematically. Gaseous O2 replenished the surface oxygen, hence maintaining the production of free radicals and promoting the removal of Hg0. SO2, HCl, and NO inhibited Hg0 removal in the absence of O2 due to the competitive adsorption and consumption of free radicals. However, SO2 and HCl significantly enhanced Hg0 removal with the participation of O2, while NO exhibited obviously inhibitory effect even with the assistance of O2. H2O also decreased the Hg0 oxidation capacity owing to the competitive adsorption and reduction of HgO. The optical fiber monolith reactor exhibited much superior Hg0 removal capacity than the powder reactor. Utilization of Ce/TiO2 catalyst coupling with an optical fiber monolith reactor provides a cost-effective method for removing Hg0 from coal-fired flue gas. [ABSTRACT FROM AUTHOR]

Background: Cancer-induced bone pain (CIBP) is the pain caused by bone metastasis from malignant tumors, and the largest source of pain for cancer patients. miR-300 is an important miRNA in cancer. It has been shown that miR-300 regulates tumorigenesis of various tumors. Objective: This study aims to investigate the role of miR-300 in CIBP and its underlying molecular mechanisms in vitro and in vivo. Methods: We constructed CIBP model in rats and investigated the mechanism through which miR-300 affects CIBP. We first examined expression level of miR-300 in CIBP rats and then tested the effect of its overexpression. Next, we identified the target of miR-300 using TargetScan analysis and double luciferase assay. Finally, we studied genetic interactions between miR-300 and its target and their roles in CIBP. Results: We found that miR-300 was downregulated in CIBP rats. Overexpression of miR-300 significantly attenuated cancer-induced neuropathic pain (p < 0.01). Furthermore, TargetScan analysis and double luciferase assay show High Mobility Group Box 1 (HMGB1) is a target of miR-300. Notably, HMGB1 is overexpressed in CIBP rats, while up-regulation of miR-300 significantly suppresses expression of HMGB1 (p < 0.01). Moreover, knockdown of HMGB1 by siRNA significantly relieves cancer-induced neuropathic pain in rats (p < 0.01). On the other hand, HMGB1 overexpression partially blocked the effect of miR-300 on cancer-induced nerve pain. Conclusion: miR-300 relieves cancer-induced neuropathic pain by inhibiting HMGB1 expression. These results may be beneficial for the treatment of CIBP in clinical practice. [ABSTRACT FROM AUTHOR]

The Ningxia Hui Autonomous Region of China (Ningxia), one of main agriculture areas in northwest China, has been severely affected by drought. Based on observed meteorological data, outputs of 20 global climate models and drought disaster data, future climate change and relevant drought hazard in the twenty-first century were projected in Ningxia, with the scenarios of RCP2.6 and RCP4.5; the risks of people, crop, and agriculture economy to drought disasters are quantitatively assessed, with the application of physical vulnerability curve models, probability distribution functions and Monte Carlo simulation method. It is found that the climate in Ningxia is likely to have a warming and wetting tendency in the twenty-first century. The extent of drought hazard is likely to increase. The increase rate is greater under RCP4.5 than that under RCP2.6. In general, the risks of population, crop, and agriculture to drought disasters are likely to increase in Ningxia in the twenty-first century. The magnitude of increase is likely to reach the greatest in the immediate term (2016–2035), followed by the increase in the medium term (2046–2065), and the long term (2081–2100). In comparison with RCP2.6, the drought disaster risks under the scenario of RCP4.5 are likely to increase further in three periods of the twenty-first century. The findings of this work have potential to provide data support for drought disaster risk management and support risk-based decision-making. [ABSTRACT FROM AUTHOR]

The stability of a fractured rock mass around a subsurface opening is critical to tunnel excavation. The traditional underground excavation analysis is based on a continuum description of randomly distributed discrete pre-existing fractures. In contrast to this, we have developed an improved hybrid finite element method (FEM) to investigate the stability of fractured rocks around an excavation by incorporating the outputs into the FEM codes. The proposed model consists of a discrete fracture network (DFN) model and cohesive zone model (CZM). The DFN model automatically generates a fracture network with a given fracture opening distribution and provides grid generation strategy to the FEM. The CZM captures material failure and intersection and surface contacts through the fracture element with different constitutive laws. As a case study, a DFN model was formulated for the underground excavation at Jinping Hydropower Station, in light of the input requirements of our model, and its deformation analysis was performed. The comparison analysis of rock deformation was made for excavation in both intact rock mass and fractured rock mass under the same boundary conditions. The numerical results show that two different modes of rock failure exist in these two rock masses and that intense deformation at the fractures intersected by the tunnel is responsible for fractured rock mass instability. The proposed approach was verified using data from field investigations. A larger displacement can be produced if the rock mass is weakened by a key block. A sensitivity analysis was carried out to investigate the effects of different model parameters on deformation variations. This study provides an insightful understanding of the deformation of fractured rock mass during tunnel excavation. [ABSTRACT FROM AUTHOR]

Ramie, flax, hemp, kenaf and Apocynum venetum (A. venetum) are all natural bast fibers which are composed of different content of cellulose, hemicellulose, lignin and other gum. The inherent functionality of these bast fibers is worth studying. In this study, cotton and polyester (PET) fibers were chosen as the control, UV protection and antiphotoaging ability of these bast fibers were all tested and analyzed. Results showed that hemp, kenaf and A. venetum composite films (CFs), which had high ability of UV absorbance, possessed higher Ultraviolet Protection Factor value of 180.48, 85.35 and 82.97 respectively, much higher than that of ramie, flax CFs and the control samples. PET fibers revealed the strongest antiphotoaging ability of all with a 76% retention of initial strength after photoaging for 48 h. The semi-degummed fibers, such as flax, kenaf and hemp fibers had more gum residues and stronger UV absorption of extracted solution, and could reserve 67, 69 and 56% of their initial strength after accelerated photoaging for 48 h, respectively. These semi-degummed bast fibers showed better antiphotoaging ability than that of the completed degummed fibers such as ramie and A. venetum. [ABSTRACT FROM AUTHOR]

Nano-structured zinc sulfide (Nano-ZnS) has been demonstrated to be a promising alternative to activated carbon (AC) for controlling mercury emission from coal combustion flue gas. The ultimate fate of the mercury-laden Nano-ZnS after mercury capture is mostly disposed in landfill with fly ashes. Thus, the stability of mercury adsorbed on the Nano-ZnS is of considerable significance in the secured disposal of fly ash after mercury removal and in the commercial application of the Nano-ZnS sorbent for removal of mercury from coal combustion flue gas. In this work, a modified toxicity characteristic leaching procedure (TCLP) was conducted to evaluate the leachability of mercury on the Nano-ZnS. The effects of leachate pH value, leaching time, liquid-to-solid ratio, and acid rain types on mercury leaching from the mercury-laden Nano-ZnS were systematically investigated. The TCLP results show that the concentration of mercury in leachate was far below the safe limit (200 μg/L) as imposed by the US Environmental Protection Agency (EPA) for classifying a material as a hazardous waste. All the key parameters that generally affected metal leaching rate exhibited slight effect on mercury leaching from the mercury-laden Nano-ZnS. Leaching tests at various highly severe conditions resulted in less than 0.01% mercury leaching from the mercury-laden Nano-ZnS. Sequential selective extraction tests demonstrated that mercury sulfide (HgS) was the dominant adsorption product on the Nano-ZnS, which guaranteed the excellent stability of mercury adsorbed on the Nano-ZnS.ᅟ [ABSTRACT FROM AUTHOR]

Multiferroic BiHoFeMnO (x = 0.025, 0.05, 0.075, 0.10 and 0.1) powder samples were successfully prepared by sol-gel technique. The effect of Ho, Mn co-doping on the properties of structural, electrical, optical and ferroelectric have been systematic investigated. X-ray diffraction (XRD) patterns reveal that Ho, Mn co-substitution leads to a structural transition. The scanning electron microscope (SEM) shows that the grains of all the samples are asymmetrical and anomalous in shape and the particle size of the samples decrease from 200 to 500 to ~100 nm with doping Ho and Mn in BFO. UV-Visible absorption spectra exhibit that co-doping can reduce the direct optical band gap from 2.40 to ~1.77 eV after doping Ho and Mn. Electric measurements demonstrate that both of the leakage current density and ferroelectric properties can be improved obviously by Ho and Mn co-doping as a result of the suppression of oxygen vacancies. [ABSTRACT FROM AUTHOR]

The pure BiFeO (BFO) and (Nd, Zn)-co-doped BFO nanoparticles were prepared by a sol-gel method. The crystal structure and optical and multiferroic properties of the samples were systematically investigated. Rietveld refinement showed that the samples crystallized in rhombohedral R3c structure. In UV-visible diffuse absorption spectra, an apparent blue shift can be observed after co-doping, which indicates a possible application in photocatalyst and photoconductive devices. Compared with a pure BFO sample, the leakage current density of the x = 0.05 sample decreases about 3 orders of magnitude. The remanent magnetization ( M ) of the x = 0.10 sample reaches 0.105 emu/g while the coercive field ( H ) is as high as 7.0 kOe. The (Nd, Zn) co-doping into BFO nanoparticles has been proved to be an effective way to improve the optical and multiferroic properties. [ABSTRACT FROM AUTHOR]

Tetragonal BiFeO (BFO), which has a giant spontaneous polarization, has attracted a great deal of attention recently. In this paper, we systematically study the structural, magnetic, electronic and optic properties of BFO, BiFeMn O (BFMM), and BiFeTiMn O (BFMT). Results show that doping Ti and Mn into the Fe sites increases the c/ a ratio and enhances the magnetization of BiFeO from 0 to 5 μ. The crystal symmetry changes from orthogonality to tetragonality with half of the Mn atoms being replaced by Ti in BiFeMn O , which suppresses the energy splitting of the Mn 3d orbitals and thus enlarge the band gap to 1.21 eV for BiFeTiMn O . Our calculated Bader charge and charge density difference show that the smallest volume of BiFeMn O arises from the strong Mn-O bonds in BiFeMn O . Further investigations indicate similar optical behaviors for BiFeO and BiFeTiMn O . However, BiFeMn O exhibits strong absorption in the infrared region for the transition from O 2p to Mn ${e_{g}^{2}}$ and $t_{2g}^{3}$ . [ABSTRACT FROM AUTHOR]

In this paper, a series of nickel-species loaded graphitic carbon nitride (g-CN) nanohybrid photocatalysts were successfully fabricated via a simple thermal treatment process and characterized by XRD, FT-IR, XPS, SEM, TEM, UV-vis DRS and PL technologies. Photocatalytic tests displayed that the nanohybrids possessed remarkable photocatalytic activity for methylene blue (MB) degradation compared with pure g-CN and P25 TiO under visible-light irradiation. Moreover, the activity can be further enhanced by adjusting the pyrolysis temperature and the amount of nickel salt. The maximal photocatalytic efficiency was achieved over the sample that pyrolysed at 650 °C with Ni content of 5% (in precursor), in which 92.1% of MB was degraded under visible light within 2 h. The present work could provide considerable reference value for the study of non-noble metal modified g-CN and pollutant degredation catalysts. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Pure BiFeO (BFO) and doped BiNdFeCrO ( x = 0.025, 0.05, and 0.075) nanoparticles were prepared by a sol-gel method. The doping effects were systematically investigated on the structural, morphological, magnetic, and ferroelectric properties. The dopant results in forming nanoparticles, and the (Nd, Cr) co-doped BFO nanoparticles show excellent ferromagnetic and ferroelectric properties. The proposed mechanism for the co-doped BFO provides an alternative strategy to form nanoparticles with enhanced multiferroic properties. [ABSTRACT FROM AUTHOR]

The present work addresses the influence of Ca doping and (Eu, Ca) co-doping into BiFeO on its corresponding structural, magnetic, and ferroelectric properties. XRD results show that Bi site doped with Ca and Eu could result in a transition of crystal structure. Analysis of magnetic hysteresis data reveals a further enhancement of magnetism in the (Eu, Ca)co-doped samples which is explained by the structural distortions and the magnetically active characteristic of Eu ions. High remnant polarization at room temperature was observed in the BiEuCaFeO samples by measuring the electric hysteresis loops due to Eu doping suppressing the formation of Fe and oxygen vacancies. [ABSTRACT FROM AUTHOR]

The multiferroic BiCaFeO, BiCaFeCoO, BiCaFeNiO, BiCaFeCuO samples were prepared by a simple sol-gel method. Rietveld refinement of X-ray diffraction data and Raman spectra reflect a structural phase transition from single phase (rhombohedral, pure BiFeO) to two phase coexistence (rhombohedral R3c and cubic Fm-3 m). The structural distortion of BiCaFeNiO is very marked. SEM images show the co-doped nanoparticles having an average size of 50 nm. A contribution from the leakage current have been observed in the P-E loops. XPS results reveal that the concentration of Fe and oxygen vacancy decreased after transition metal elements (Co, Ni, Cu) doped into BiCaFeO. Moreover Co, Ni doping can enhance the saturation magnetization, while Cu doping can enhance the coercive field in BiCaFeO. [ABSTRACT FROM AUTHOR]

Most environmental perturbations have a direct or indirect deleterious impact on photosynthesis, and, in consequence, the overall energy status of the cell. Despite our increased understanding of convergent energy and stress signals, the connections between photosynthesis, energy and stress signals through putative common nodes are still unclear. Here we identified an endoplasmic reticulum (ER)-localized adenine nucleotide transporter1 (ER-ANT1), whose deficiency causes seedling lethality in air but viable under high CO, exhibiting the typical photorespiratory phenotype. Metabolic analysis suggested that depletion of ER-ANT1 resulted in circadian rhythm disorders in sucrose synthesis and induced sucrose signaling pathways, indicating that the ER is involved in the regulation of vital energy metabolism in plants. In addition, the defect of ER-ANT1 triggers ER stress and activates the unfolded protein response in plant cells, suggesting ER stress and photorespiration are closely linked. These findings provide an important evidence for a key role of ER-localized ER-ANT1 in convergent energy and stress signals in rice. Our findings support the idea that ATP is a central signal involved in the plant response to a variety of stresses. [ABSTRACT FROM AUTHOR]

Pure and magnetic transition metal (TM = V, Cr, and Mn)-doped copper nitride (CuN) films with a preferred orientation of (100) were successfully prepared by reactive rf magnetron sputtering with an appropriate optical band gap for potential application in solar energy conversion. The incorporation of V or Mn can make the lattice constant smaller while it becomes larger after the inset of Cr into CuN. The calculated equilibrium structural parameters reveal that the unit cell of CuN could expand by inserting TM in the center or Cu vacancy of CuN. The SEM shows boundaries disappeared grains of V-doped sample, small spherical-like grains of Cr-doped sample, and greater glomerate crystal particles of Mn-doped CuN. The band gap becomes minor (1.50 to 1.22 eV) after doping with V or Cr and larger (1.50 to 1.56 eV) for Mn-doped samples, which realized the adjustable optical band gap of CuN films by doping with TM. What is more, TM in the center vacancy of CuN can improve magnetic properties more effectively than that of TM in the Cu vacancy of CuN. And Cr doping in the center gives the biggest magnetic moment of 0.2656 μ . [ABSTRACT FROM AUTHOR]

This article reports on the synthesis of water dispersible carbon quantum dots (CDs) by a one-step hydrothermal method using polyamidoamine (PAMAM) and (3-aminopropyl)triethoxysilane (APTES) as a platform and passivant. The resulting CDs are highly uniform and finely dispersed. The synergistic effect between PAMAM and APTES on the surface of the CDs results in a fluorescence that is much brighter than that of CDs modified with either APTES or PAMAM only. The fluorescence of the co-modified CDs is quenched by Hg(II) ions at fairly low concentrations. Under the optimum conditions, the intensity of quenched fluorescence drops with Hg(II) concentration in the range from 0.2 nM to 10 μM, and the detection limit is 87 fM. The effect of potentially interfering cations on the fluorescence revealed a high selectivity for Hg. The fluorescent probe was applied to the determination of Hg(II) in (spiked) waters and milk and gave recoveries between 95.6 and 107 %, with relative standard deviation between 4.4 and 6.0 %. [ABSTRACT FROM AUTHOR]

The back analysis method has been widely used as an indirect method of determining geotechnical parameters based on field measurements. The number of parameters and their initial values greatly influence the reliability and efficiency of back analysis. Therefore, sensitivity analysis is often employed to select high sensitivity parameters that have more greater impact on measured back analysis values. The orthogonal design method was first utilized to select geotechnical parameters for back analysis. The optimized parameter values obtained from an orthogonal design table can be used as the initial back analysis values, so as to avoid optimisation algorithm searching in local parameter spaces. By introducing a penalty function to the objective function, back analysis of the geotechnical parameters is changed into an unconstrained optimisation problem, whereby the Nelder-Mead method can then be employed. To verify the feasibility of the proposed back analysis method, a case study was conducted to determine the rock mass parameters for the Houziyan underground powerhouse complex. [ABSTRACT FROM AUTHOR]