Search

Background: Causal mediation analysis plays a crucial role in examining causal effects and causal mechanisms. Yet, limited work has taken into consideration the use of sampling weights in causal mediation analysis. In this study, we compared different strategies of incorporating sampling weights into causal mediation analysis. Methods: We conducted a simulation study to assess 4 different sampling weighting strategies-1) not using sampling weights, 2) incorporating sampling weights into mediation "cross-world" weights, 3) using sampling weights when estimating the outcome model, and 4) using sampling weights in both stages. We generated 8 simulated population scenarios comprising an exposure (A), an outcome (Y), a mediator (M), and six covariates (C), all of which were binary. The data were generated so that the true model of A given C and the true model of A given M and C were both logit models. We crossed these 8 population scenarios with 4 different sampling methods to obtain 32 total simulation conditions. For each simulation condition, we assessed the performance of 4 sampling weighting strategies when calculating sample-based estimates of the total, direct, and indirect effects. We also applied the four sampling weighting strategies to a case study using data from the National Survey on Drug Use and Health (NSDUH). Results: Using sampling weights in both stages (mediation weight estimation and outcome models) had the lowest bias under most simulation conditions examined. Using sampling weights in only one stage led to greater bias for multiple simulation conditions. Discussion: Using sampling weights in both stages is an effective approach to reduce bias in causal mediation analyses under a variety of conditions regarding the structure of the population data and sampling methods. [ABSTRACT FROM AUTHOR]

In this paper, a unique hydrolysis reaction process for the production of 4‐Aminoantipyrine (AA) is investigated. A liquid‐phase analytical method for AA is established, and the amount of sulfuric acid, reaction temperature, reaction time are studied. On the basis of single factor experiments, the response surface method (RSM) is used to systematically optimize the conditions of the hydrolysis reaction. The optimum conditions are n(AT‐SO4): n(H2SO4)=0.73, the reaction temperature is 98 °C, the reaction time is 91 min, and the AA yield reaches 90.80 %. Compared with the previous process, the yield of AA is improved and colloids are significantly reduced. Under optimum process conditions, a kinetic model is constructed in the range of 358 K–373 K, which activation energy, Ea=33.21 kJ/mol, and the pre‐exponential factor, A=1586.84. In addition, the product AA is characterized by IR analysis, LC‐MS analysis, GC‐MS analysis and hydrolysis reaction mechanism are investigated. [ABSTRACT FROM AUTHOR]

This paper interprets an image space accelerating branch and bound algorithm for globally solving a class of multiplicative programming problems (MP). In this algorithm, in order to obtain the global optimal solution, the problem (MP) is transformed into an equivalent problem (P2) by introducing new variables. By utilizing new linearizing relaxation technique, the problem (P2) can be converted into a series of linear relaxation programming problems, which provide the reliable lower bound in the branch and bound search. Meanwhile, an image space accelerating method is constructed to improve the computational performance of the algorithm by deleting the subintervals which have no global optimal solution. Furthermore, the global convergence of the algorithm is proved. The computational complexity of the algorithm is analyzed, and the maximum iterations of the algorithm are estimated. Finally, numerical experimental results show that the algorithm is robust and efficient. [ABSTRACT FROM AUTHOR]

This paper presents a disturbance observer-based model predictive of super-twisting control for Soft Open Point (SOP). First, with the consideration of the disturbances caused by parameter mismatches and unmodelled dynamics, a super-twisting sliding-mode observer (STO) is proposed to observe the disturbances, and the observed disturbances are introduced into the inner-loop as the compensation to improve the anti-disturbance of SOP system. Second, the outer-loop controller is designed by applying the super-twisting sliding-mode control (STC) approach to improve the dynamic performance and robustness. Third, to deal with large current harmonics by traditional model predictive control (MPC), a Three-Vector-based MPC (TV-MPC) is proposed to increase the number of voltage vectors in a sampling time. Finally, it is verified by simulations that the proposed method can reduce current harmonics, DC-side voltage setting time and improve the dynamic performance of SOP system effectively. In case of parameter mismatches, the proposed observer can observe the disturbances correctly to enhance the robustness of the SOP system. [ABSTRACT FROM AUTHOR]

Soft open point (SOP) can improve the flexibility and reliability of power supplies; thus, they are widely used in distribution network systems. Traditional single-vector model predictive control (SV-MPC) can quickly and flexibly control the power and current at both ports of the SOP. However, SV-MPC can only select one voltage vector in a sampling time, producing large current ripples, and power fluctuations. In order to solve the above problems, this paper proposes a three-vector-based low complexity model predictive control (TV-MPC). In the proposed control method, two effective voltage vectors and one zero voltage vector are selected in a sampling time. For the two-port SOP, methods are given to judge the sectors on both sides and select the voltage vectors. Furthermore, the calculation method of the distribution time is proposed as well. Finally, the effectiveness of the proposed method is verified by steady-state and dynamic-state simulation results compared with the SV-MPC. [ABSTRACT FROM AUTHOR]

• Injection parameters of H 2 -rich gas over sintering process were optimized. • Experiment and numerical simulation were used to elucidate function mechanism. • A novel method on hydrogen-rich energy application in practical plants was developed. H 2 -rich gas has been widely regarded as a promising energy to substitute fossil energy in iron ore sintering process for CO 2 reduction. This investigation mainly focused on researching the influences of H 2 -rich gas injection parameters over sintering bed on sintering performance, and elucidated the potential function mechanism through both experiment and numerical simulation. Results indicated that increasing injection concentration and prolonging injection time within a proper range improved sinter quality, and the recommended value was 0.6∼0.8 % and 8 min, respectively. Injecting H 2 -rich gas at earlier sintering stages achieved greater improvement in sintering quality compared with the ones injecting at later sintering stages, and the recommended injection area was 5∼13min. Both experiment and numerical simulation results indicated that injecting H 2 -rich improved the thermal patterns of sintering bed, with extended high-temperature areas for increasing the generation of high-strength calcium ferrite. Especially when injecting H 2 -rich gas under the recommended parameters, the heat distribution in sintering bed was optimized and the sintering quality of upper sintering layer was obviously improved. Finally, an injection method for guiding the industrial application with its essence to inject H 2 -rich at earlier sintering stages was proposed. The research findings provide a promising way for the efficient utilization of clean energy in iron ore sintering plants. [ABSTRACT FROM AUTHOR]

The rapid development of many open source and commercial image editing software makes the authenticity of the digital images questionable. Copy-move forgery is one of the most widely used tampering techniques to create desirable objects or conceal undesirable objects in a scene. Existing techniques reported in the literature to detect such tampering aim to improve the robustness of these methods against the use of JPEG compression, blurring, noise, or other types of post processing operations. These post processing operations are frequently used with the intention to conceal tampering and reduce tampering clues. A robust method based on the color moments and other five image descriptors is proposed in this paper. The method divides the image into fixed size overlapping blocks. Clustering operation divides entire search space into smaller pieces with similar color distribution. Blocks from the tampered regions will reside within the same cluster since both copied and moved regions have similar color distributions. Five image descriptors are used to extract block features, which makes the method more robust to post processing operations. An ensemble of deep compositional pattern-producing neural networks are trained with these extracted features. Similarity among feature vectors in clusters indicates possible forged regions. Experimental results show that the proposed method can detect copy-move forgery even if an image was distorted by gamma correction, addictive white Gaussian noise, JPEG compression, or blurring. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rapid all laser-based fabrication of silicon microchannel device. • Laser engraving of microchannels, laser drilling of inlet/outlet holes, laser sintering of film heater, and laser welding for packaging. • Application in microchannel heat sink for miniaturized devices. Microchannel heat sinks have been recognized as efficient cooling platforms for thermal management of miniaturized devices because of their compact structure. Unlike most microfabrication processes, laser micromachining is a versatile direct writing method to rapidly produce microchannels in brittle substrates such as silicon wafers. In this study, an all-laser fabrication method is proposed to fabricate a microfluidic heat sink for silicon devices. Lasers are used for engraving microchannels on a silicon wafer, drilling inlet/outlet holes in quartz glass cover, and welding the Si sample and quartz glass cover. The entire fabrication process is completed within two hours. The microchannel surface is converted into a hydrophilic wall as proven by contact angle measurement, and a water flow is easily introduced to the channel as a cooling fluid. The boiling heat transfer performance of the fabricated microfluidic channel is evaluated by applying heat to the bottom of the device. A micro-heater placed underneath the Si substrate is also prepared using a laser to induce selective sintering of a conductive Ag layer. The heat generated by the heater is successfully removed by boiling heat transfer, and the critical heat flux is measured to be ∼ 55.2 W/cm2 at a water flux of 208 kg/m2s. [ABSTRACT FROM AUTHOR]

In this paper, a Canny operator-based method using PCNN (Pulse-Coupled Neural Network) is proposed for color image segmentation. The coarse location information of the salient object and the background is first estimated based on the distribution of the detected key-points. An image is then over-segmented into super-pixels and their histograms are computed. The saliency of a super-pixel is obtained according to the maximum of variance ration and Shannon entropy. Color image segmentation is implemented using PCNN based on Canny operator edge detection method. The proposed method is compared with state-of-the-art methods on the widely used dataset, and the experiments show that it overall obtains more accurate results. [ABSTRACT FROM AUTHOR]

Robots are very essential for modern nuclear power plants to monitor equipment conditions and eliminate accidents, allowing one to reduce the radiations on personnel. As a novel robot, a soft robot with the advantages of more degrees of freedom and abilities of continuously bending and twisting has been proposed and developed for applications in nuclear power industry. Considering the radiation and high-temperature environment, the overall performance improvement of the flexible materials used in the soft nuclear robot, such as the tensile property and gamma-ray shielding property, is an important issue, which should be paid attention. Here, a flexible gamma-ray shielding material silicone-W-based composites were initially doped with nano titanium oxide and prepared, with the composition of 20 silicone-(80-x) W-(x) TiO2, where x varied from 0.1 to 2.0 wt.%. Structural investigations on SEM and EDS were performed to confirm the structure of the prepared composites and prove that all the chemicals were included in the compositions. Moreover, the tensile property of the composites at 25, 100, and 150 °C were investigated to study the effect of working temperature on the flexibility of the compositions. The attenuation characteristics including the linear attenuation coefficients and mass attenuation coefficients of the prepared silicone-W or silicone-W-TiO2-based composites with respect to gamma ray were investigated. The stability of the silicone–tungsten-TiO2-based composite at high temperature was studied for the first time. In addition, the influence of nano TiO2 additive on the property's variation of silicone-W-based composites was initially studied. The comparison of the properties such as the tensile elongation, thermal stability, and gamma-ray shielding of the synthesized silicone-W and silicone-W-TiO2 composites showed that the addition of nano TiO2 powders could be useful to develop novel gamma-ray-shielding materials for radiation protection of soft robots or other applications for which soft gamma-ray-shielding materials are needed. [ABSTRACT FROM AUTHOR]

Conductive fibers are essential building blocks for implementing various functionalities in a textile platform that is highly conformable to mechanical deformation. In this study, two major techniques were developed to fabricate silver-deposited conductive fibers. First, a droplet-coating method was adopted to coat a nylon fiber with silver nanoparticles (AgNPs) and silver nanowires (AgNWs). While conventional dip coating uses a large ink pool and thus wastes coating materials, droplet-coating uses minimal quantities of silver ink by translating a small ink droplet along the nylon fiber. Secondly, the silver-deposited fiber was annealed by similarly translating a tubular heater along the fiber to induce sintering of the AgNPs and AgNWs. This heat-scanning motion avoids excessive heating and subsequent thermal damage to the nylon fiber. The effects of heat-scanning time and heater power on the fiber conductance were systematically investigated. A conductive fiber with a resistance as low as ~2.8 Ω/cm (0.25 Ω/sq) can be produced. Finally, it was demonstrated that the conductive fibers can be applied in force sensors and flexible interconnectors. [ABSTRACT FROM AUTHOR]

In this paper, a full-order terminal sliding-mode control method is proposed for the rectifier side and the inverter side of the soft open point (SOP). The rectifier-side DC voltage control system consists of the voltage- and current-loops with controllers which are designed using full-order sliding-mode (FOSM) to enhance the dynamic performances and anti-disturbance. The integral type virtual control signal without chattering is designed to compensate for the unmatched uncertainties including external disturbances and some parameter perturbations. The full-order terminal sliding-mode (FOTSM) controller for the current-loop can force the current response to track its reference in finite time. The inverter side power control system is designed to regulate the power. The FOTSM controller for the power-loop ensures the power-tracking accuracy under a disturbed condition. Finally, the simulations demonstrate the effectiveness of the proposed controllers for the rectifier and inverter sides in the soft open point (SOP). [ABSTRACT FROM AUTHOR]

Favipiravir was chosen as a model for study on cocrystal screening of nucleoside analog. Seven coformer candidates were selected according to supramolecular synthon method and verified with molecular modeling and hot-stage. Only 4-amino benzoic acid was able to form cocrystal with the color transformation from white to yellow. Fluorescence study was investigated and compared during cocrystallization. Due to the fluorescent emission nature of nitrogen heterocyclic nucleoside analog, fluorescence could also be utilized as a promising tool in screening cocrystals. This study provides an efficient pathway toward nucleoside analog cocrystal and affords a fluorescent screening method for drug cocrystal research. [ABSTRACT FROM AUTHOR]

Machine learning models perform satisfactorily in landslide displacement prediction, but they are generally black-box models that are difficult to gain the trust of decision-makers. Therefore, a three-stage prediction framework based on the Hodrick–Prescott (HP) filter, double exponential smoothing (DES), natural gradient boosting (NGBoost), and Shapley additive explanations (SHAP) was proposed. The framework quantifies the uncertainty in the predictions and provides fully transparent outputs. In the first stage, the HP filter decomposes cumulative displacements into trend and period displacements. The second stage uses DES and NGBoost to predict them separately. In the third stage, we compute the SHAP values of the features to analyze the impact of the features on the model output. It is applied to the Bazimen and Baishuihe landslides in the Three Gorges Reservoir area and compared with other literature. The results show that the framework can achieve high accuracy in both point and interval prediction, and its performance is similar to or even better than other models. And it is easier to operate and applicable to a wider range of people. Most importantly, the framework can interpret the model, allows users to verify the consistency of the model prediction basis with the landslide evolution mechanism, and reduces random errors by optimizing the data. Overall, the prediction framework can capture the complex nonlinear relationships between features, solving the current challenge of machine learning models that cannot be applied in the final optimization scenario due to the lack of convincing, and providing a reliable tool for intelligent disaster prevention. [ABSTRACT FROM AUTHOR]

Phosphogypsum, which contains toxic components (e.g., heavy metal elements and fluoride), is one of the byproducts of phosphoric acid production, and filling subgrade is one of the recycling methods for it. In this study, phosphogypsum was stabilized by lime to improve the mechanical properties [California bearing ratio (CBR), resilience modulus, unconfined compressive strength, and shear strength], water stability, and harmful substances dissolubility. Combined with scanning electron microscopy, the strength formation and water stability enhancement mechanism of lime-stabilized phosphogypsum (LSP) were explored. The results demonstrated that the mechanical properties of LSP were better with the lime content of 6%–10%. The CBR, resilience modulus, unconfined compressive strength, and shear strength were 3.35 times, 2.46 times, 8.61 times, and 1.39 times that of plain phosphogypsum, respectively. An intensity prediction model with a correlation of 97% was constructed. The CBR and resilience modulus softening coefficient of LSP reached best values when lime content was 6%–8%. The leaching concentration of arsenic, chromium, and lead of LSP with 2% lime met the quality standards of groundwater levels I, II, and IV, respectively. Fluoride and phosphate were not detected in LSP when lime content was greater than 6.0%. The results show that LSP is feasible as subgrade filler. Considering the mechanical properties, water stability, and dissolution of hazardous substances of LSP, it is recommended to add 6%–8% lime content to LSP as highway subgrade filler. [ABSTRACT FROM AUTHOR]

Herein we synthesized biochar/iron oxide composite (C/α‐Fe2O3/γ‐Fe2O3) by two‐step calcination method. The prepared C/α‐Fe2O3/γ‐Fe2O3 had a highly pure and a concentration ratio of α‐Fe2O3 and γ‐Fe2O3 about 1 : 1. The optical properties of as‐synthesized C/α‐Fe2O3/γ‐Fe2O3 show a lower bandgap energy (1.90 eV) than that of pure C/α‐Fe2O3 (2.02 eV). The effects of different biochar composite catalysts on the removal of amino black were investigated. Upon illumination, the total removal rate of amino black dye by C/α‐Fe2O3/γ‐Fe2O3 catalyst reached 98 %, which was about 1.7 times that of C/α‐Fe2O3. In addition, the coercivity and the remanence intensity of C/α‐Fe2O3/γ‐Fe2O3 is respectively 1.81 times and 7.17 times that of C/α‐Fe2O3. The catalyst could be magnetically separated and reused for five times with a slight loss of its reactivity. The study of biochar composite provides a new direction for the removal of toxic organic dye in wastewater. [ABSTRACT FROM AUTHOR]

The influence of boiling time (10 –120 min) on nutritional and antioxidant properties of Lentinus edodes pieces and broth was investigated. The results showed that the primary nutrients contents and antioxidant activities of L. edodes pieces decreased with the prolongation of boiling time, while ergosterol content increased. The nutrients contents in L. edodes broth presented an uptrend, and the antioxidant activities increased rapidly in the first 30 min, and then kept stable or decline, which was positively correlated with the change of total phenolic content. Microstructure observation showed that boiling treatment destroyed the cell wall of L. edodes, leading to the dissolution and loss of cell wall components and cytoplasmic contents. From the point of nutrition, the optimal boiling time for L. edodes pieces is 30 min and for broth preparation is 60 min. This study provides a useful reference for rational cooking or processing L. edodes and other mushrooms. [ABSTRACT FROM AUTHOR]

Homography estimation serves an important role in many computer vision tasks. Depending heavily on hand‐craft feature quality, traditional methods degenerate sharply in scenes with low texture. Existing deep homography methods can handle the low‐texture problem but are not robust for scenes with low overlap rates and/or illumination changes. This paper proposes a novel unsupervised homography estimation method that can simultaneously handle such low overlap and illumination change. Specifically, a powerful module, named global transformer contextual encoder (GTCE) is first designed, together with a correlation encoder to effectively aggregate global contextual information and reduce matching ambiguity between feature maps. Moreover, a hybrid photo‐perceptual loss for unsupervised homography estimation is proposed. The proposed loss function considers alignment information on both pixel level and perceptual level thus helping this network to be more adaptive to various scenes, including normal cases and illumination change cases. The results of extensive experiments on synthetic and real‐world datasets demonstrate the superiority of this proposed method over current state‐of‐the‐art solutions especially on challenging scenes with low overlap rates, repetitive patterns and illumination changes. [ABSTRACT FROM AUTHOR]

Abstract Sensor devices using different poly(3,4-ethylene dioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) based active layers were fabricated with all solution processes. It was found the devices of pristine PEDOT:PSS presented high response to humidity change, but little response to ammonia (NH 3). In contrast, the DMSO doped PEDOT:PSS devices were nearly insensitive to humidity change, and exhibited significantly improved responsivity to NH 3. Incorporation of AgNWs into the DMSO doped PEDOT:PSS film further enhanced the responsivity to NH 3 , while maintaining insensitivity to humidity changes. The mechanisms for such different sensing properties were revealed. Finally, the fabricated NH 3 and humidity sensors using different PEDOT:PSS based films were integrated with a near field communication (NFC) chip to realize a flexible system, which was able to be attached on the packaging film for monitoring the meat freshness, with the sensing data being read out wirelessly by a smart phone. Graphical abstract Image 1 Highlights •The sensing mechanisms to ammonia and humidity of sensors using different PEDOT:PSS based active layers were revealed. •PEDOT:PSS based humidity insensitive ammonia sensors and ammonia insensitive humidity sensors were fabricated with all solution processes, respectively. •The PEDOT:PSS based ammonia and humidity sensors were integrated with a near field communication (NFC) chip to realize a smart packaging system for monitoring the meat freshness. [ABSTRACT FROM AUTHOR]

In this paper, a unique process for the production of methyl anthranilate (MA) was investigated. The factors of the phthalimide/sodium hypochlorite/methanol molar ratio, reaction temperature, hydrolysis temperature, and water consumption on the yield and purity of MA were analyzed. Response surface methodology (RSM) was used to optimize conditions for the semi-batch synthesis process of MA. The best synthetic conditions for the formation of MA were reaction temperature 0.5 °C, hydrolysis temperature 70 °C and n (phthalimide)/ n (sodium hypochlorite)/ n (methanol) = 1:2.03:5.87, and water consumption m (H2 O)/ m (phthalimide) = 7.16:1. The yield of MA could reach 90% under the optimal conditions, which is more than 10% higher than that of the previous semi-batch process. Furthermore, the reaction mechanism was investigated by infrared spectroscopy analysis, and the mechanism of ester group formation and the structure of intermediate products are proposed. The byproduct of the reaction was studied by GC-MS analysis, a byproduct called 2-cyanobenzoic acid has been discovered. Therefore, an unprecedented reaction mechanism of the whole synthesis process is proposed. [ABSTRACT FROM AUTHOR]

Liver fibrosis (LF) is a common reversible consequence of chronic liver damage with limited therapeutic options. Yinchen Gongying decoction (YGD) composed of two homologous plants: (Artemisia capillaris Thunb , Taraxacum monochlamydeum Hand.-Mazz.), has a traditionally application as a medicinal diet for acute icteric hepatitis. However, its impact on LF and underlying mechanisms remain unclear. This study aims to assess the impact of YGD on a carbon tetrachloride (CCl 4) induced liver fibrosis and elucidate its possible mechanisms. The study seeks to establish an experimental foundation for YGD as a candidate drug for hepatic fibrosis. LC-MS/MS identified 11 blood-entry components in YGD, and network pharmacology predicted their involvement in the FoxO signaling pathway, insulin resistance, and PI3K-AKT signaling pathway. Using a CCl 4 -induced LF mouse model, YGD's protective effects were evaluated in comparison to a positive control and a normal group. The underlying mechanisms were explored through the assessments of hepatic stellate cells (HSCs) activation, fibrotic signaling, and inflammation. YGD treatment significantly improved liver function, enhanced liver morphology, and reduced liver collagen deposition in CCl 4 -induced LF mice. Mechanistically, YGD inhibited HSC activation, elevated MMPs/TIMP1 ratios, suppressed the FoxO1/TGF-β1/Smad2/3 and YAP pathways, and exhibited anti-inflammatory and antioxidant effects. Notably, YGD improved the insulin signaling pathway. YGD mitigates LF in mice by modulating fibrotic and inflammatory pathways, enhancing antioxidant responses, and specifically inhibiting FoxO1/TGF-β1/Smad2/3 and YAP signal pathways. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Catalytic methane/air combustion in a micro-channel was parametrically studied. • Operating parameters correlate with the heterogeneous and heterogeneous reactions. • The heterogeneous reactions are insensitive to the inlet velocity. • The homogeneous reaction is enhanced at the increased inlet temperature. • Increasing the equivalence ratio moves the combustion zone upstream. Micro-combustion is a promising technology for addressing global energy consumption challenges; however, its practical implementation is hindered by a limited understanding of the underlying reaction characteristics. To address this, a comprehensive numerical investigation was conducted using a well-established two-dimensional (2D) steady model to examine the influence of key operating parameters (e.g., inlet velocity, equivalence ratio, and inlet temperature) on catalytic methane/air combustion in micro-channels. The results show that the heterogeneous reaction exhibits limited sensitivity to changes in inlet velocity, whereas the homogeneous reaction shows substantial enhancement with increasing inlet temperature. With the increment of inlet velocity, the peak value of stage III- heterogeneous ignition (conversion of CO to CO 2 and H 2 to H 2 O) decreases and levels off once u in ≥ 0.50 m/s. Simultaneously, the minimum value of S (the ratio of heat released by the heterogeneous reaction to that of the total reaction) decreases as well. As the equivalence ratio is increased, the combustion zone shifts towards the upstream direction. The value of S initially increases and then decreases, reaching a maximum of 17.61 % at Φ = 0.95. Raising the inlet temperature results in the upstream movement of the flame, accompanied by reduced combustion heat release, lower combustion temperature, and diminished intensity of homogeneous combustion. The influence of the heterogeneous reaction on combustion is more pronounced under operating conditions with lower inlet velocities, an equivalence ratio approaching 0.95, and higher inlet temperature. Additionally, under the condition of higher inlet velocities, an equivalence ratio close to 1.0, and elevated inlet temperature, the heterogeneous reaction aids in igniting the homogeneous reaction more effectively. [ABSTRACT FROM AUTHOR]

It has been proved that dual-armature permanent magnet (PM) machines have higher power density than conventional PM machines under the same copper loss. However, the thermal conditions of these machines are different. This paper makes a fair comparison between a dual-armature linear switched flux PM machine (DALSFPMM) and a linear surface-mounted PM machine (LSPMM) by considering both electromagnetic performances and thermal conditions. First, the topologies of two machines and platform are introduced. Then, the 2D and 3D finite element (FE) models are employed for the electromagnetic and thermal analyses, respectively. During the machine optimization, the thermal analysis is used to determine the copper loss under the fixed machine dimensions, while the electromagnetic analysis is used to optimize the machine dimensions under the fixed copper loss. After iterations, two machines are optimized and their performances are compared. Under the limitations of 80 °C maximum PM temperature and 120 °C maximum winding temperature, the DALSFPMM can exhibit 38% higher thrust force density for the continuous duty and up to 43% higher thrust force density for the short-time duty. Finally, a prototype machine of DALSFPMM is tested to validate the analyses. [ABSTRACT FROM AUTHOR]

Surface ignition is the first and also the important step for iron ore sintering, which provides the initial source of energy to trigger the whole reactions. This investigation mainly focused on revealing the relationship between surface ignition and sintering performance, and elucidated the deep mechanism. Results indicate that the quality of sinter in the surface layer can be effectively improved by adjusting the ignition parameters. The preferred ignition parameters include ignition temperature of 1050 °C, ignition duration of 1 min and heat preservation of 1−2 min. The function mechanism of improved sinter quality is attributed to the increased high temperature duration for minerals melting, the enlarged melting zone, and the decreased cooling velocity. These changes facilitate the formation of enough adhesive phase of calcium ferrite, more of which generated in acicular morphology with high mechanical strength. Optimizing the ignition process reduced the solid fuel consumption due to the improved sintering performance, which then decreased the emission of NO and SO 2. The research findings are of great significance for providing a guide for the design of desirable ignition system and making further contributions to energy conservation and emission reduction during sintering. [ABSTRACT FROM AUTHOR]

For the practical combustion of ammonia (NH 3) in air, ammonia jet entrains the combustion product inside the furnace, and the reaction zone is diluted with a significant amount of H 2 O; thus, the impact of H 2 O on NH 3 oxidation cannot be ignored. In this study, NH 3 oxidation was conducted under N 2 and H 2 O atmospheres in a jet-stirred reactor. Experimental and numerical investigations were conducted to analyze the impact of various parameters, including the temperature, equivalence ratio, H 2 O volume fraction, and residence time. The NO formation is enhanced as T increases, while it is inhibited as Φ or X H2O increases. The N 2 O and NO concentrations are an order of magnitude when T ≤ 1375 K, and the peak N 2 O concentration occurs at T ≈ 1375 K and Φ = 0.5. The presence of 20 % H 2 O reduces NO and N 2 O concentrations by 61.5 % and 29.5 %, respectively, at Φ = 0.5 and T = 1375 K. To reduce NO x formation with an acceptable concentration of unburned NH 3 , the recommended operation condition of NH 3 oxidation is obtained. This study presents a new underlying understanding of the formation of NO x during NH 3 oxidation under N 2 and H 2 O atmospheres. • NH 3 oxidation with wide Φ and high H 2 O concentration is studied in a JSR. • 20 % H 2 O addition reduces NO concentration by 61.5 % at Φ = 0.5 and T = 1375 K. • The peak N 2 O concentration occurs at Φ = 0.5 and T ≈ 1375 K. • The optimal condition with low NO x and unburned NH 3 concentration is obtained. [ABSTRACT FROM AUTHOR]

Microsupercapacitors have attracted significant attention due to several of their advantageous characteristics such as lightweight, small volume, and planar structure that is favorable for high mechanical flexibility. Among the various micro supercapacitor forms, those with laser-induced graphene (LIG) electrodes are promising as flexible energy storage devices. While LIG microelectrodes can be fabricated simply by direct laser writing, the capacitance and energy density of these devices are limited because of the relatively low density of LIG, which leads to low surface areas. These limitations could be overcome by densifying the LIG. Here, we report the use of densified laser-induced graphene (d-LIG) to fabricate flexible micro supercapacitors. Interdigitated d-LIG electrodes were prepared by duplicate laser pyrolysis of a polyimide sheet by using a CO2 laser. A PVA-H2SO4 gel-type electrolyte was then applied to the d-LIG electrode surface to assemble a d-LIG micro supercapacitor. This d-LIG micro supercapacitor exhibited substantially increased capacitance and energy density versus conventional low-density LIG micro supercapacitors. While the d-LIG electrode exhibited a substantial change in resistance when subjected to bending at a radius of 3 mm, the change in the capacitance of the d-LIG micro supercapacitor was negligible at the same bending radius due to reinforcement by the infiltrated poly(vinyl alcohol) (PVA) electrolyte, demonstrating the potential application of d-LIG micro supercapacitors in wearable electronics. [ABSTRACT FROM AUTHOR]

Leaf tooth can indicate several systematically informative features and is extremely useful for circumscribing fossil leaf taxa. Moreover, it can help discriminate species or even higher taxa accurately. Previous studies extract features that are not strictly defined in botany; therefore, a uniform standard to compare the accuracies of various feature extraction methods cannot be used. For efficient and automatic retrieval of plant leaves from a leaf database, in this study, we propose an image-based description and measurement of leaf teeth by referring to the leaf structure classification system in botany. First, image preprocessing is carried out to obtain a binary map of plant leaves. Then, corner detection based on the curvature scale-space (CSS) algorithm is used to extract the inflection point from the edges; next, the leaf tooth apex is extracted by screening the convex points; then, according to the definition of the leaf structure, the characteristics of the leaf teeth are described and measured in terms of number of orders of teeth, tooth spacing, number of teeth, sinus shape, and tooth shape. In this manner, data extracted from the algorithm can not only be used to classify plants, but also provide scientific and standardized data to understand the history of plant evolution. Finally, to verify the effectiveness of the extraction method, we used simple linear discriminant analysis and multiclass support vector machine to classify leaves. The results show that the proposed method achieves high accuracy that is superior to that of other methods. [ABSTRACT FROM AUTHOR]

The attachment of microbial biomass on solid surfaces, also referred to as biofouling, is a universal phenomenon that occurs in natural and engineering systems. However, traditional antibiofouling surfaces based on either the release of biocidal compounds or surface chemical/physical design have some drawbacks, such as the high cost, the complicated process, the low accuracy, and the limitation to achieve coatings over large area. Herein, to overcome these problems, a superhydrophobic coating is fabricated via spraying the mixture of hydrophobized zinc oxide nanoparticles and epoxy resin. The zinc oxide nanoparticles form a multiscale roughness, and the epoxy resin promotes the robustness of the coating. The so‐formed superhydrophobic coating resists the attachment of protein, bacteria, and marine algae. It is expected that the so‐developed superhydrophobic coating can be applied in the fields of biomedical instruments, antimicrobial material, marine platform, and ships. [ABSTRACT FROM AUTHOR]

Hydrogen-rich gas and steam are widely regarded to be of great potential to mitigate CO 2 emissions in iron ore sintering, these gases can regulate heat distribution in the sintering machines by replacing fossil fuels. However, most sintering machines only use one of the gases as the injecting medium, the potential of this technology has not been developed. In this paper, a multiple gaseous medium injection method contained natural gas and steam was experimentally investigated to solving this problem. Sintering tests were arranged to study the appropriate scheme of coupling injection and its influence on the sintering process, and the flue gas analyzer was used to detect the composition of the sintering flue gas in real time. Better sintering indexes were achieved by injecting the above two gaseous medium when the coke breeze ratio is unchanged, the results show that when 0.8 vol% natural gas is injected into the 4–14min, 0.15 vol% steam is injected into the 10–14 min, and 0.25 vol% steam is injected into the 15–18 min of sintering, the sintering yield increases by 2.42%, and the tumbler index increases by 2.72%. Under the above parameters, the coke breeze ratio can be reduced by 12.99%, the average NOx emissions decreased by 19.5%, and the average CO emissions decreased by 36.96% in the coupling injection interval (4–18min). After calculating the amount of coke breeze and natural gas in the optimal coupling injection sintering, CO 2 emissions decreased by 7.66%, about 17.15 kg/t -sinter. Moreover, the PFR model was used to simulate the associated gas phase reaction after coupling injection which shows H 2 O significantly reduced CO emissions and change the reduction pathway of NO. Generally, sintering fuel consumption and greenhouse gas emissions have also been reduced, providing theoretical support for the change of iron ore sintering energy structure. [Display omitted] • Natural gas and steam coupling injection in iron ore sintering for the first time. • The energy structure is optimized to partial replace fossil fuel with gas-based fuel. • The heat distribution and sintering speed after coupling injecting are analyzed. • PFR model shows the NO reduction pathway will change when steam is present. • CO 2 emission can be reduced by 91400 t/year with coupling injection sintering. [ABSTRACT FROM AUTHOR]

• Cervical carcinoma is a leading cause of mortality in women worldwide. • Lignans, as phytochemicals, have therapeutic potential for cancer cell lines. • An electrochemical cytosensor evaluated pinoresinol activity on HeLa cells. • Pinoresinol induced apoptosis in HeLa cells and hindered HeLa cell cycle. • MTS, flow cytometry, and fluorescent imaging confirmed the cytosensor results. A sensitive, simple, label-free electrochemical cytosensor was developed to evaluate the anticancer activity of pinoresinol against human cervical carcinoma (HeLa) cells. HeLa cells were immobilised on carboxylated multi-walled carbon nanotubes (c-MWCNTs)/gold nanoparticles (AuNPs) nanocomposite-modified glassy carbon electrodes. Scanning electron microscopy, transmission electron microscopy, Fourier transform-infrared spectroscopy, and X-ray diffractometry were used to characterise the morphology, crystallinity, and composition of the nanocomposites. Cyclic voltammetry was used to characterise and optimise the cytosensor. Both c-MWCNTs and AuNPs increased the electron-transfer rate between the HeLa cells and the electrode, retaining good cell compatibility. The concentration of HeLa cells immobilised on the nanocomposite electrode exhibited a good correlation with the impedance values determined by electrochemical impedance spectroscopy in the range of 102–106 cells/mL (detection limit of 102 cells/mL) with R2 = 0.975. HeLa cells were then immobilised on the nanocomposite electrode at a concentration of 104 cells/mL, and it was used as a cytosensor. The anticancer activity of pinoresinol from Cinnamomum camphora was evaluated by determining the median inhibitory concentration using the proposed cytosensor. For comparison, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry, and fluorescent imaging were simultaneously performed, which confirmed the results of the cytosensor. The cytosensor is promising for future applications in anticancer drug screening. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is one of the most lethal types of primary brain tumors in adults with a median survival of less than 15 months. Although comprehensive clinical treatment strategies including surgical resection followed by radiotherapy and chemotherapy are widely applied, the prognosis for GBM patients remains dismal. The Nuclear Factor-κB (NF-κB) signaling pathway is a complex network linking extracellular stimuli to cell survival and proliferation, and aberrant activation of NF-κB signaling has been implicated in the propagation of a wide range of cancers. However, the underlying mechanism of NF-κB activation still requires further investigation. Here, we report that crumbs homolog 2 (CRB2) is markedly up-regulated in human GBM relative to non-tumor tissues or normal astrocytes. Clinically, enriched CRB2 could be observed in high grade glioma with IDH IDH wild-type and 1p19q co-deletion and implied poor outcome in GBM. Consistent with this, malignant characteristics of GBM cells including proliferation, migration, invasion and tumorigenesis were significantly suppressed by lentivirus knock-down of CRB2. Furthermore, exogenous overexpression of CRB2 enhanced the malignant biological signatures of GBM cells as well as therapy resistance to temozolomide (TMZ). To further investigate the molecular mechanisms responsible, bioinformatics analysis was performed using 3 public databases, with the result that CRB2 was found to correlate closely with tumor necrosis factor α (TNFα)–NF–κB signaling. Mechanistically, elevated CRB2 increased the phosphorylation of IκB-kinase α (IKKα), thus activating NF-κB via reduction of Ikβ protein. Taken together, these data suggest that CRB2 might be a reliable prognostic biomarker and potential therapeutic target for GBM. [ABSTRACT FROM AUTHOR]

With the objectives of reducing CO 2 emissions and applying hydrogen-enriched gas in the iron ore sintering process, a mathematical model was developed to simulate the natural gas (NG) injection in the sintering process. The accuracy of the model was verified via sinter pot tests. Additionally, an environmental assessment of CO 2 mitigation was performed. Moreover, the effects of the injection quantity, location, and intensity on the sintering process were examined. Sintering process parameters were adopted to quantitatively assess the NG injection technology. The results indicated that this technology can reduce the CO 2 emissions. The CO 2 mitigation dosage is 11.75 kg/ton sinters when 15% solid fuel is replaced with NG. The melting zone thickness (MZT) and binding liquid phase amount in the upper sintering bed are gradually improved with NG injection quantity increased gradually, which indicates that the holding time of the high temperature zone in the upper bed is prolonged. Furthermore, the injection locations and intensities affect the sintering process. Earlier injection allows more heat storage and forms more binding liquid phase in the upper bed. Low intensity injection reduces the MZT of the sintering bed and negatively affects the sintering process. [Display omitted] • A model is built to simulate natural gas (NG) injection in sintering process. • Three combustion parameters are adopted to assess the NG injection technology. • Low CO 2 emissions and reasonable heat utilisation is proven for this technology. [ABSTRACT FROM AUTHOR]

Strong synergistic interactions existed between lactoferrin (LF) and α-lactalbumin (ALA) during heating at pH 7.0, leading to the formation of thermal aggregates and gels at low total protein concentration. As a result of non-covalent interactions (the decreased electrostatic repulsion and increased attractive hydrophobic attraction) and covalent interactions (in particular S-S bridge exchanges), the aggregation between unfolded Lf molecules and/or ALA molecules occurred via a co-fusion, nucleation and growth processes. The denaturation degree of LF and the concentrations of ALA affected the degree of aggregation and gelation of LF and ALA. [Display omitted] • There existed strong synergistic interactions between lactoferrin (LF) and α-lactalbumin (ALA) during co-heating. • ALA led to hydrophobic residues located in the interior of LF to be exposed further during co-heating. • New intermolecular disulfide bonds, mainly unstable ones, were formed during co-heating. • LF engaged readily in thermal aggregation, while ALA mainly assisted the LF thermal aggregation. • Co-fusion, nucleation and growth mechanisms involved in the aggregation and gelation processes. The synergistic enhancement in the thermal co-aggregation and gelation of lactoferrin (LF), a heat sensitive protein, and α-lactalbumin (ALA), a heat stable protein, was investigated at pH 7.0. Heating temperatures (70 °C and 90 °C; 30 min) and ALA concentrations (0–0.5 mM) significantly affected the structural characteristics of the resultant thermal aggregates and gels. The turbidity and size of LF-ALA thermal aggregates were increased with increasing ALA concentration; at a low total protein concentration of 0.57 mM, LF-ALA gels can be formed. The presence of ALA led to some hydrophobic residues originally located in the interior of LF to be exposed further during heating. New intermolecular disulfide bonds, mainly unstable ones, were formed between LF molecules and/or ALA molecules during co-heating. The aggregation of LF and ALA was a gradual denaturation process, accompanied by an increase in β-sheet content and decrease in α-helix content. Random spherical aggregates with large size (1–5 μm) were observed by transmission electron microscopy, clearly confirming the nucleation and growth of LF with ALA. There existed strong rheological synergism between LF and ALA, thereby leading to a large reduction in gelation times (4–11 min) with increasing ALA concentration and heating temperature. Considering these data, LF and ALA played different and indispensable roles in thermal aggregation and gelation: LF engaged readily in thermal aggregation, while ALA mainly assisted the LF thermal aggregation. Three types of mechanisms (co-fusion, nucleation and growth) involved in the aggregation and gelation processes. In all, the data of the current study has enhanced the comprehension of heat sensitive protein-heat stable protein thermal aggregation and gelation, and may help to design LF-based new ingredients for the control of food textures and delivery systems for food and pharmaceutical applications. [ABSTRACT FROM AUTHOR]