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This paper presents a study on the impact of circuit parameters on the transmission of electrical energy in wireless power transfer systems designed for intelligent sensing devices within the urban electric power Internet of Things (IoT). Relying on the essential principles of resonant mutual inductance models, the paper conducts an analytical investigation into the phenomena of power-frequency splitting characteristics, efficiency-frequency splitting characteristics, and efficacy synchronization characteristics within wireless energy transmission technologies. The investigation includes a detailed analysis of a wireless power transfer system model operating at 100 kHz, delineating how varying circuit parameters influence the system's efficiency. Via the utilization of graphical software and computational programming for simulation modeling, this research delved into the dynamics between key parameters such as equivalent load and coupling coefficient and their influence on distinct splitting phenomena. This rigorous approach substantiated the validity of the proposed power-frequency and efficiency-frequency splitting characteristics outlined in the study. Based on the analytical results, it is shown that selecting an appropriate equivalent load or utilizing impedance matching networks to adjust the equivalent load to a suitable size is crucial in consideration of the system's output power, voltage withstand level, and transmission efficiency. The research findings provide a theoretical basis for the design of wireless power supply systems for non-directly buried cable front-end sensing devices. [ABSTRACT FROM AUTHOR]

Millettia speciosa Champ. (MSCP) enjoys widespread recognition for its culinary and medicinal attributes. Despite the extensive history of MSCP cultivation, the disparities in quality and bioactivity between wild and cultivated varieties have remained unexplored. In this study, 20 wild and cultivated MSCP samples were collected from different regions in China. We embarked on a comprehensive investigation of the chemical constituents found in both wild and cultivated MSCP utilizing UHPLC-Q-Exactive Orbitrap-MS technology and multivariate analysis such as principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). In total, 62 chemical components were unequivocally identified or tentatively characterized. Via the multivariate statistical analysis, we successfully pinpointed nine compounds with the potential to serve as chemical markers, enabling the differentiation between wild and cultivated MSCP varieties. Moreover, both genotypes exhibited substantial antioxidant and anti-fatigue properties. The bioactivities of wild MSCP were marginally higher when compared to their cultivated counterparts. This study illuminates the impressive antioxidant and anti-fatigue potential present in both wild and cultivated MSCP genotypes, further augmenting the allure of this species and opening new avenues for the economic valorization of MSCP. Hence, this study provides a valuable method for the identification and quality control of MSCP and a method in chemistry and pharmacology to assess an alternative possibility for cultivated MSCP. [ABSTRACT FROM AUTHOR]

Rapid non-destructive testing technologies are effectively used to analyze and evaluate the linoleic acid content while processing fresh meat products. In current study, hyperspectral imaging (HSI) technology was combined with deep learning optimization algorithm to model and analyze the linoleic acid content in 252 mixed red meat samples. A comparative study was conducted by experimenting mixed sample data preprocessing methods and feature wavelength extraction methods depending on the distribution of linoleic acid content. Initially, convolutional neural network Bi-directional long short-term memory (CNN-Bi-LSTM) model was constructed to reduce the loss of the fully connected layer extracted feature information and optimize the prediction effect. In addition, the prediction process of overfitting phenomenon in the CNN-Bi-LSTM model was also targeted. The Bayesian-CNN-Bi-LSTM (Bayes-CNN-Bi-LSTM) model was proposed to improve the linoleic acid prediction in red meat through iterative optimization of Gaussian process acceleration function. Results showed that best preprocessing effect was achieved by using the detrending algorithm, while 11 feature wavelengths extracted by variable combination population analysis (VCPA) method effectively contained characteristic group information of linoleic acid. The Bi-directional LSTM (Bi-LSTM) model combined with the feature extraction data set of VCPA method predicted 0.860 Rp2 value of linoleic acid content in red meat. The CNN-Bi-LSTM model achieved an Rp2 of 0.889, and the optimized Bayes-CNN-Bi-LSTM model was constructed to achieve the best prediction with an Rp2 of 0.909. This study provided a reference for the rapid synchronous detection of mixed sample indicators, and a theoretical basis for the development of hyperspectral on-line detection equipment. [ABSTRACT FROM AUTHOR]

Claystone is potentially the main rock formation for the deep geological disposal of high-level radioactive nuclear waste. A major factor that affects the deformation of the host medium is effective stress. Therefore, studying the effective stress principle of claystone is essential for a stability analysis of waste disposal facilities. Consolidated drained (CD) tests were carried out on claystone samples to study their effective stress principle in this paper. Firstly, two samples were saturated under a specified confining pressure and pore pressure for about one month. Secondly, the confining pressure and pore pressure were increased to a specified value simultaneously and then reverted to the previous stress state (the deformations of the samples were recorded during the whole process). Different incremental combinations of the confining pressure and pore pressure were tried at this step. Finally, the effective stress coefficients of the samples were obtained through a back analysis. Furthermore, some potential influencing factors (the neutral stress and loading rate) of the effective stress coefficient were also studied through additional tests. Some interesting results are worth mentioning: (1) the effective stress coefficient of claystone is close to one; (2) the neutral stress and loading rate may have little effect on the effective stress coefficient of claystone. [ABSTRACT FROM AUTHOR]

Rolling treatments have been identified as a promising fabrication and deformation processing technique for graphene/metal composites with high performance. However, it is still a challenge to choose appropriate rolling parameters to achieve high strength, ductility and electrical conductivity of the composite simultaneously. In this study, graphene/Cu composites were prepared with an in situ growth method and rolling treatment. The effects of rolling deformation and temperature on the microstructural evolution of graphene and Cu grains, interface bonding between graphene and the matrix, mechanical and electrical properties were systemically investigated. The cold-rolled composite with 85% deformation displayed a maximum ultimate strength of 548 MPa, a high elongation of 8.8% and a good electrical conductivity of 86.2% IACS. This is attributed to oriented graphene arrangement and matrix grain refinement. Our research provides a comprehensive understanding for the rolling behavior of graphene/Cu composites, and can promote the development of graphene-based composites with high performance. [ABSTRACT FROM AUTHOR]

A weldable Al–Mg–Zn–Sc alloy was produced using vacuum induction melting and an argon-protected casting method to achieve high strength and ductility, and the effects of heat treatment on the microstructure evolution and mechanical properties of Al–Mg–Zn–Sc alloys were comparatively investigated. The results reveal that fine equiaxed grains with an average grain size of 40 μm in an as-cast Al–Mg–Zn–Sc alloy change little after heat treatments, bringing about a grain-boundary strengthening of 46.1 MPa. The coarse T-Mg32(Al, Zn)49 phases at grain boundaries are completely dissolved into the matrix through solid-solution treatment, and T-Mg32(Al, Zn)49 with diameters ranging from 10 to 25 nm and Al3Sc with diameters ranging from 5 to 20 nm gradually precipitate during the artificial aging process. The Mg solid solubility is 4.67% in the as-cast Al–Mg–Zn–Sc alloy, and it increased to 5.33% after solid-solution treatment and dramatically decreased to 4.15% after post-aging treatment. The contributions of solid-solution strengthening to as-cast, post-solid-solution and post-aging Al–Mg–Zn–Sc alloys are 78.2 MPa, 85.4 MPa and 72.3 MPa, respectively. The precipitation strengthening of the post-aging alloy is 49.7 MPa, which is an increase of 21% in comparison to that of both as-cast and post-solid-solution alloys. The alloy achieves an optimal tensile strength of 355.3 MPa, yield strength of 175 MPa and elongation of 22% after undergoing solid-solution treatment. [ABSTRACT FROM AUTHOR]

The innovation of structural forms and the increase in the energy-saving requirements of buildings have led to higher requirements regarding the application conditions of steel slag foam concrete (SSFC) to ensure that the SSFC has a lower thermal conductivity and sufficient compressive strength, which has become the primary research object. Through a comprehensive consideration of 7 d compressive strength and thermal conductivity, the recommend mix ratio of SSFC was as follows: maximum SS size = 1.18 mm, water–cement ratio = 0.45, replacement rate of SS = 20–30%. Moreover, a theoretical formula was derived to determine thermal conductivity versus porosity based on fractal theory. The measured values of the foam concrete found elsewhere corroborate the fractal relationship regarding thermal conductivity versus porosity. This fractal relationship offers a straightforward and scientifically sound way to forecast the thermal conductivity of SSFC. [ABSTRACT FROM AUTHOR]

Simple Summary: The formation of primordial germ cells (PGCs) is the basis of molluskan reproduction, but limited information is reported on this topic. PRDI-BF1 and RIZ homology domain-containing proteins (PRDMs), especially PRDM1 (also known as BLIMP1) and PRDM14, have been reported to be essential for the formation of PGCs. In this study, we systematically characterized the putative PRDMs in a bivalve mollusk species, Mulinia lateralis, and analyzed their sequence structures, phylogenetic relationships, and expressional profiles. Furthermore, we analyzed the temporal–spatial expression patterns of Ml-prdm1 and Ml-prdm14 RNA in early embryos and larvae. Our study suggests that Ml-prdm1 may function as an important regulator of PGC formation in M. lateralis. Mollusca represents one of the ancient bilaterian groups with high morphological diversity, while the formation mechanisms of the precursors of all germ cells, primordial germ cells (PGCs), have not yet been clarified in mollusks. PRDI-BF1 and RIZ homology domain-containing proteins (PRDMs) are a group of transcriptional repressors, and PRDM1 (also known as BLIMP1) and PRDM14 have been reported to be essential for the formation of PGCs. In the present study, we performed a genome-wide retrieval in Mulinia lateralis and identified 11 putative PRDMs, all of which possessed an N-terminal PR domain. Expressional profiles revealed that all these prdm genes showed specifically high expression levels in the given stages, implying that all PRDMs played important roles during early development stages. Specifically, Ml-prdm1 was highly expressed at the gastrula stage, the key period when PGCs arise, and was specifically localized in the cytoplasm of two or three cells of blastula, gastrula, or trochophore larvae, matching the typical characteristics of PGCs. These results suggested that Ml-prdm1-positive cells may be PGCs and that Ml-prdm1 could be a candidate marker for tracing the formation of PGCs in M. lateralis. In addition, the expression profiles of Ml-prdm14 hinted that it may not be associated with PGCs of M. lateralis. The present study provides insights into the evolution of the PRDM family in mollusks and offers a better understanding of the formation of PGCs in mollusks. [ABSTRACT FROM AUTHOR]

During the early development of marine invertebrates, planktic larvae usually occur, and their body surfaces often form specific types of cilia that are involved in locomotion and feeding. The echiuran worm Urechis unicinctus sequentially undergoes the formation and disappearance of different types of body surface cilia during embryonic and larval development. The morphological characteristics and molecular mechanisms involved in the process remain unclear. In this study, we found that body surface cilia in U. unicinctus embryos and larvae can be distinguished into four types: body surface short cilia, apical tufts, circumoral cilia and telotrochs. Further, distribution and genesis of the body surface cilia were characterized using light microscope and electron microscope. To better understand the molecular mechanism during ciliogenesis, we revealed the embryonic and larval transcriptome profile of the key stages of ciliogenesis in U. unicinctus using RNA-Seq technology. A total of 29,158 differentially expressed genes (DEGs) were obtained from 24 cDNA libraries by RNA-Seq. KEGG pathway enrichment results showed that Notch, Wnt and Ca2+ signaling pathways were significantly enriched during the occurrence of apical tufts and circumoral cilia. Furthermore, all DEGs were classified according to their expression pattern, and DEGs with similar expression pattern were grouped into a module. All DEG co-expression modules were correlated with traits (body surface short cilia, apical tufts, circumoral cilia and telotrochs) by WGCNA, the results showed DEGs were divided into 13 modules by gene expression patterns and that the genes in No. 7, No. 8 and No. 10 modules were to be highly correlated with the occurrence of apical tufts, circumoral cilia and telotrochs. The top 10 hub genes in the above three modules were identified to be highly correlated with ciliogenesis, including the reported cilium-related gene Cnbd2 and unreported cilium-related candidate genes FAM181B, Capsl, Chst3, TMIE and Innexin. Notably, Innexin was included in the top10 hub genes of the two modules (No. 7 and No. 8), suggesting that Innexin may play an important role in U. unicinctus apical tufts, circumoral cilia and telotrochs genesis. This study revealed the characteristics of ciliogenesis on the body surface of U. unicinctus embryos and larvae, providing basic data for exploring the molecular mechanism of ciliogenesis on the body surface. [ABSTRACT FROM AUTHOR]

Three-dimensional porous network encapsulation strategy is an effective means to obtain composite phase-change materials (PCMs) with high heat storage capacity and enhanced thermal conductivity. Herein, macroporous reduced graphene oxide (rGO) aerogels with adjustable pore size are prepared by the emulsion template method and hydrothermal reduction process. Further, the shape-stabilized rGO-aerogel-based composite PCMs are constructed after the combination of 3D porous rGO supports and paraffin wax (PW) through vacuum melting infiltration. By regulating the pore structure of the rGO aerogel network, the rGO-based composite PCMs achieve excellent energy storage properties with a phase-change enthalpy of 179.94 J/g for the loading amount of 95.61 wt% and an obvious enhancement in thermal conductivity of 0.412 W/m−1·K−1, which is 54.89% higher than pristine PW and enduring thermal cycling stability. The obtained macroporous rGO-aerogel-based composite PCMs with high thermal storage and heat transfer performance effectively broaden the application of PCMs in the field of thermal energy storage. [ABSTRACT FROM AUTHOR]

Processing of Chinese herbal medicines (CHMs) is a traditional pharmaceutical technology in Chinese medicine. Traditionally, proper processing of CHMs is necessary to meet the specific clinical requirements of different syndromes. Processing with black bean juice is considered one of the most important techniques in traditional Chinese pharmaceutical technology. Despite the long-standing practice of processing Polygonatum cyrtonema Hua (PCH), there is little research on the changes in chemical constituents and bioactivity before and after processing. This study investigated the influence of black bean juice processing on the chemical composition and bioactivity of PCH. The results revealed significant changes in both composition and contents during processing. Saccharide and saponin content significantly increased after processing. Moreover, the processed samples exhibited considerably stronger DPPH and ABTS radical scavenging capacity, as well as FRAP-reducing capacity, compared to the raw samples. The IC50 values for DPPH were 1.0 ± 0.12 mg/mL and 0.65 ± 0.10 mg/mL for the raw and processed samples, respectively. For ABTS, the IC50 values were 0.65 ± 0.07 mg/mL and 0.25 ± 0.04 mg/mL, respectively. Additionally, the processed sample demonstrated significantly higher inhibitory activity against α-glucosidase and α-amylase (IC50 = 1.29 ± 0.12 mg/mL and 0.48 ± 0.04 mg/mL) compared to the raw sample (IC50 = 5.58 ± 0.22 mg/mL and 0.80 ± 0.09 mg/mL). These findings underscore the significance of black bean processing in enhancing the properties of PCH and lay the foundation for its further development as a functional food. The study elucidates the role of black bean processing in PCH and offers valuable insights for its application. [ABSTRACT FROM AUTHOR]

Sinter ore quality directly affects the stability of blast furnace production. In terms of both physical and chemical properties, the main indicators of sinter quality are the TFe content, alkalinity, and drum index. By analyzing the massive historical data on the sinter production of a steel company, this study proposes a sinter quality prediction system based on Granger causality analysis and a stacking integration algorithm. First, based on real historical data of sintering production in steel enterprises (including coal gas pressure, ignition temperature, combustion air pressure, etc.), data preprocessing of raw data was carried out using a combination of feature engineering and the sintering process. Second, Pearson correlation analysis, Spearman correlation analysis, and Granger causality analysis were used to screen out the characteristic parameters with a strong influence on the target variable of sinter quality (drum Index, TFe, alkalinity). Third, a prediction model for sinter quality parameters was developed using a stacking integration algorithm pair for training. Finally, a program development tool was used to realize the establishment and online operation of a sinter ore quality prediction system. The test results showed that the predicted goodness of fit of the model for the TFe content, alkalinity (R), and drum index were 0.942, 0.958, and 0.987, respectively, and the model calculation time met the actual production requirements. By establishing a suitable model and running the program online, the real-time prediction of the main indicators of sinter quality was realized to guide production promptly. [ABSTRACT FROM AUTHOR]

The root of Millettia speciosa Champ. (MSCP) is used in folk medicine and is popular as a soup ingredient. The root is composed of the rhizome and radix, but only the radix has been used as a food. Thus, it is very important to compare the chemical components and antioxidant activities between the rhizome and radix. The extracts were analyzed by UHPLC-Q-Exactive Orbitrap-MS and multivariate analysis, and the antioxidant activities were evaluated by 2,20-azinobis (3-ethylbenzothiazo-line-6-sulfonic acid) diammonium salt (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays. Ninety-one compounds were detected simultaneously and temporarily identified. Ten compounds were identified as chemical markers to distinguish the rhizome from the radix. The antioxidant activities of the radix were higher than the rhizome. Correlation analysis showed that uvaol-3-caffeate, 3-O-caffeoyloleanolic acid, and khrinone E were the main active markers for antioxidant activity, which allowed for the rapid differentiation of rhizomes and the radix. Therefore, it could be helpful for future exploration of its material base and bioactive mechanism. In addition, it would be considered to be used as a new method for the quality control of M. speciosa. [ABSTRACT FROM AUTHOR]

Taking as an example the practical teaching of the design of children's solar-energy-based ultraviolet disinfection products, we analyzed the practical activities in four stages of teaching—case background, research methods, product design, and practical results—in the practical teaching mode based on solar green energy. This paper presents and proposes a design solution for a solar-powered green energy-based multifunctional inductive UV disinfection product for children to provide additional services for school interventions and improve public health in primary and secondary schools. This new innovative design for a children's disinfection product is based on solar green energy and enhances the graded disinfection strategy in schools, reducing the number of viruses and the potential risk of virus transmission in the educational environment. The proposed program aims to be project-oriented, combining green energy concepts with innovative educational concepts, classroom content with social prevention products, digital technology with innovative thinking, promoting the development of innovative and digital abilities of teachers and students, and promoting the development of practical teaching in digital media. The practical results show that the model has positive teaching effects, practical value for students, schools and society, cultivation of digital innovation ability of teachers and students, and reference significance for practical teaching. [ABSTRACT FROM AUTHOR]

The demand for shale gas has propelled researchers to focus on precise and high-resolution stratigraphic divisions for homogeneous shales, of which the late-Ordovician Wufeng (O3w) and the early-Silurian Longmaxi (S1l) formations in southwest China are two of the best candidates for shale gas exploration in China. However, systematic chemostratigraphic work for these strata is still sparse, and the existing chemostratigraphic work either lack representativeness in terms of the proxies used or are subjective during their division procedures. Thus, automatic division process based on multi proxies and an objective statistical technique was applied to establish a quantitative, high-resolution, and robust chemostratigraphic scheme for the Wufeng and lower Longmaxi shales. The geochemical analysis unveils that the Wufeng and Lower Longmaxi shales show prominent heterogeneities in terrigenous inputs, redox conditions, and paleoproductivity, enabling the potential application of chemostratigraphy to these strata. Based on these heterogeneities, the chemostratigraphic scheme for the Wufeng and Lower Longmaxi shales has been established, and the whole strata could be divided into 13 chemozones using constrained clustering analysis. The chemostratigraphic scheme could not only be comparable to the regional sequence stratigraphic scheme but also more objective and higher-resolution. The high TOC content and brittle minerals within chemozone C1 makes it the most preferable layer for shale gas exploration and development. This research gives a systematic chemostratigraphic analysis on Wufeng and Lower Longmaxi shales, which testifies the feasibility and potential of usage of chemostratigraphy for Chinese shale gas exploration and development. [ABSTRACT FROM AUTHOR]

Cultivated land is the principal land source for urban expansion. Recent large-scale urban expansion through the occupation of cultivated land has influenced regional food security and the realization of sustainable development goals. Based on data regarding the cultivated land occupied for urban construction in the Chengdu metropolitan area from 2000 to 2018, the spatio-temporal evolution of cultivated land occupied by urban expansion was analysed using the contribution index. Based on a model comparison, the geographically weighted regression (GWR) model was used to explore the spatio-temporal pattern and evolution path of significant driving factors. The results demonstrate that (1) the total area of cultivated land occupied by urban expansion from 2000 to 2018 was 470.528 km2 and mainly concentrated in the main urban area of Chengdu City and its surrounding districts and counties. The K value continued to decline from 93.23 to 37.48, indicating that the contribution of cultivated land in urban expansion is decreasing. (2) The GWR model, with a better fitting effect, demonstrates that the significant factors that influence the cultivated land occupied by urban expansion in the study area gradually shift from population aggregation factors to food safety and the proportion of non-farming population. (3) The evolution type of the driving force is mainly dominated by continuous change, and there is significant spatial heterogeneity in the evolution path. The population density → proportion of non-farm population → grain yield → comprehensive and proportion of cultivated land → per capita fixed asset investment → comprehensive → proportion of non-farm population were typical pathways. (4) Realizing the coordination between urban system structural optimization and cultivated land protection policies in the Chengdu metropolitan area is an important way to guarantee regional food and ecological security and promote the green and high-quality development of the metropolitan area. This study can promote coordination between urban expansion and cultivated land protection in metropolitan areas and provide a reference basis for sustainable economic and social development. [ABSTRACT FROM AUTHOR]

Ningxia wolfberry is the only wolfberry product with medicinal value in China. However, the nutritional elements, active ingredients, and economic value of the wolfberry vary considerably among different origins in Ningxia. It is difficult to determine the origin of wolfberry by traditional methods due to the same variety, similar origins, and external characteristics. In the study, we have for the first time used a multi-task residual fully convolutional network (MRes-FCN) under Bayesian optimized architecture for imaging from visible-near-infrared (Vis-NIR, 400–1000 nm) and near-infrared (NIR-1700 nm) hyperspectral imaging (HSI) technology to establish a classification model for near geographic origin of Ningxia wolfberries (Zhongning, Guyuan, Tongxin, and Huinong). The denoising auto-encoder (DAE) was used to generate augmented data, then principal component analysis (PCA) was combined with gray level co-occurrence matrix (GLCM) to extract the texture features. Finally, three datasets (HSI, DAE, and texture) were added to the multi-task model. The reshaped data were up-sampled using transposed convolution. After data-sparse processing, the backbone network was imported to train the model. The results showed that the MRes-FCN model exhibited excellent performance, with the accuracies of the full spectrum and optimum characteristic spectrum of 95.54% and 96.43%, respectively. This study has demonstrated that the MRes-FCN model based on Bayesian optimization and DAE data augmentation strategy may be used to identify the near geographical origin of wolfberries. [ABSTRACT FROM AUTHOR]

Effective shale gas exploration is hindered by the need for obtaining high-resolution correlations between shale strata and the need for classifying shale facies. To address these issues, chemostratigraphy, sequence stratigraphy, and shale gas geology methods were integrated to develop a new method known as "chemical sequence stratigraphy," which was successfully applied to the Wufeng–Lower Longmaxi Formations in the upper Yangtze region. Well Huadi 1 was used as a case study, and detailed data were acquired. Multivariate statistical analyses were applied to three defined indices having different genetic significance, namely: terrigenous input intensity (TII), authigenic precipitation intensity (API), and organic matter adsorption and reduction intensity (OARI). By analyzing the trends of these three indices, the Wufeng–Lower Longmaxi Formations were divided into five fourth-order chemical sequences (from bottom to top): LCW, MCL1-1, MCL1-2, MCL1-3, and MCL1-4. The geochemical facies were named and classified using the chemical sequence stratigraphic framework. The enrichment factor (EF) transformation of elements was conducted to determine whether an element is rich or deficient. The results showed that the favorable geochemical facies in the well were EF-Al deficient, EF-Ca rich, and EF-V rich. The organic matter content and rock brittle strength were then used as chemical parameters, and it was predicted that the LCW and MCL1-1 chemical sequences most likely comprised shale gas sweet spots. This conclusion is consistent with the drilling results and indicates that our proposed method is effective and reliable. This method is further applied to the Changning Shuanghe section, the Shizhu Liutang section, and sections in the Xindi 1 well in the upper Yangtze region. The comparative study of these four sections showed that LCW and MCL1-1 are the key chemical sequences for shale gas exploration and development in the Wufeng–Lower Longmaxi Formations within the Upper Yangtze region. [ABSTRACT FROM AUTHOR]

Al-8Zn-2Mg-1.5Cu-0.15Sc-0.15Zr alloy with high-strength performance as well as good castability has been developed. In this study, effects of electromagnetic stirring melt treatment (ESMT) on microstructure and mechanical properties of the alloy in the squeeze casting process were investigated. The results show that solidification structure and mechanical properties are significantly improved by ESMT; compared with the conventional squeeze casting, the average grain size decreases from 112 μm without ESMT to 53 μm with ESMT. Meanwhile coarse primary Al3(Sc, Zr) particles unavoidably occurred in cases without ESMT disappear, and segregation degree of the main elements of Zn, Mg, Cu are greatly alleviated; the tensile strength increases from 590 MPa to 610 MPa, and the elongation increases from 9% to 11%. The structure refinement and homogenization should owe to uniform temperature and composition distribution by ESMT under squeeze casting with rapid solidification. [ABSTRACT FROM AUTHOR]

Al-Mg alloys were fabricated by hot extrusion process after vacuum + argon-protected casting. The effects of Sc microalloying on microstructure and properties of as-extruded Al-5Mg alloy were studied. The results show that alloy 2 containing Sc is partially recrystallized during hot extrusion, resulting in the structure of alloy 2 consisting of 21.8% equiaxed recrystallized structure and 78.2% fine banding structure. The grain size of alloy 2 is about 5.31 μm, which is 83.3% finer than that of alloy 1 without Sc. The sum of the yield strength increments due to grain boundary strengthening ( σ G B ) in alloy 2 is 103.59 MPa, where low angle grain boundary strengthening ( σ L A G B) is increased by a factor of 4.5, and high angle grain boundary strengthening (σ H A G B ) is increased by 73.4% compared to that of alloy 1. The addition of 0.2% Sc leads to an increase in the lattice strain and dislocation density of alloy 2, and the dislocation strength ( σ d i s ) increases to 41.85 MPa. The alloy 2 with Sc has a higher tensile strength of 380.7 MPa, which is 34.1% higher than that of alloy 1, but alloy 2 has a 46.2% reduction in elongation compared to alloy 1. [ABSTRACT FROM AUTHOR]

Aiming for hydrogen and oxidation easily produced in the melting process of Al-Mg alloys, three processes, including non-vacuum static melt treatment, non-vacuum rotary-injection purification and vacuum-stirring purification, were used to purify the Al-6Mg alloy melt. The hydrogen content and inclusion content were studied by means of the solid-state hydrogen measurement method, reduced pressure test method, FESEM and EDS. The results show that the purification effect of vacuum-stirring purification is better than that of the non-vacuum static melt treatment and non-vacuum rotary-injection purification. The hydrogen content of the melt decreases from 0.48 mL/100 gAl in the non-vacuum static treatment, to 0.32 mL/100 gAl in the non-vacuum rotary-injection purification process and to 0.10 mL/100 gAl in the vacuum-stirring purification process. The inclusion content of the melt decreases from 2.6% in the non-vacuum static treatment to 0.69% in the non-vacuum rotary-injection purification process, and to 0.39%, in the vacuum-stirring purification process. [ABSTRACT FROM AUTHOR]

In this study, Al-Mg alloys were prepared by vacuum + argon-protected casting. The effects of Sc microalloying on the microstructure and mechanical properties of Al-Mg alloy were studied. The strengthening mechanism of Al-Mg alloy with Sc was discussed. The results show that the average grain size of as-cast Al-Mg alloy with Sc reaches 36.07 μm, which is 74.4% smaller than that of alloy 1 without refiner and 32.0% of alloy 2 with 0.15% Ti. The alloy with Sc has excellent comprehensive mechanical properties, with a tensile strength of 274 MPa and an elongation of 29.67%, and its tensile strength is 10.6% higher than alloy 1 and 7.9% higher than alloy 2. There exist two kinds of fine particles in as-cast Sc-containing Al-Mg alloy, nucleated particles Al3Sc, and dispersed second-phase particles Al3(Sc, Ti). The main strengthening mechanisms of the as-cast Al-Mg alloy with Sc reveal the solid solution strengthening of Mg and the fine-grain strengthening effect caused by Sc, accounting for 57.7% and 23.9% to strengthening contribution, respectively. [ABSTRACT FROM AUTHOR]

Simple Summary: Sex formation of gonads encompasses two ancient and highly conserved biological processes, sex determination and sex differentiation. The processes are strictly regulated by a complex of gene networks. There is increasing evidence that miRNAs play key roles in many biological processes. however, information is limited in their contribution to sex differentiation in animals. In the present study, we identified the novel miRNAs involved in sex-related genes regulation and explored the miRNA–mRNA networks underlying the posttranscriptional regulation during the initial sex differentiation in Zhikong scallop, Chlamys farreri. Our findings provide an important basis for studying the sex differentiation mechanisms, as well as developing sex control techniques in bivalves. Research on expressional regulation of genes at the initial sex differentiation of gonads will help to elucidate the mechanisms of sex determination and differentiation in animals. However, information on initial sex differentiation of gonads is limited in bivalves. MicroRNAs (miRNAs) are a class of endogenous small noncoding RNAs that can regulate the target gene expression at the posttranscription level by degrading the mRNA or repressing the mRNA translation. In the present study, we investigated the small RNAs transcriptome using the testes and ovaries of Zhikong scallop Chlamys farreri juveniles with a shell height of 5.0 mm, a critical stage of initial sex differentiation of gonads. A total of 75 known mature miRNAs and 103 novel miRNAs were identified. By comparing the expression of miRNAs between the ovary and testis, 11 miRNAs were determined to be differentially expressed. GO annotations and KEGG analyses indicated that many putative target genes that matched to these differentially expressed miRNAs participated in the regulation of sex differentiation. Furthermore, two selected miRNAs, cfa-novel_miR65 and cfa-miR-87a-3p_1, were confirmed to downregulate expressions of Foxl2 (a female-critical gene) and Klf4 (a male-critical gene), respectively, using a dual-luciferase reporter analysis. Our findings provided new insights into the initial sex differentiation of gonads regulated by miRNAs in bivalves. [ABSTRACT FROM AUTHOR]

An underwater profiler is one of the popular platforms for ocean observation. Due to energy limitations, conventional underwater vehicles have a short life span, which cannot meet the needs of long-term ocean exploration. Therefore, there is a growing interest in using ocean energy such as ocean thermal energy and wave energy for driving. This study aimed to investigate an energy-saving and ocean thermal energy (OTE)-powered buoyancy driving system of the ocean profiler. The purpose of this study was to explore an ocean profiler buoyancy driving system powered by ocean thermal energy (OTE). According to the seawater profile temperature gradient, an OTE-powered electro-hydraulic control system was designed, and the dynamic characteristics of this system are simulated and analyzed by using the power bonding diagram method. Based on the results conducted from lake tests, this profiler possesses the self-driving capability for using OTE perfectly. This research can provide important guidance for the design of the buoyancy drive system of underwater vehicles. [ABSTRACT FROM AUTHOR]

Recently, there is of significant interest in developing multi-criteria decision making (MCDM) techniques with large applications for real-life problems. Making a reasonable and accurate decision on MCDM problems can help develop enterprises better. The existing MCDM methods, such as the grey comprehensive evaluation (GCE) method and the technique for order preference by similarity to an ideal solution (TOPSIS), have their one-sidedness and shortcomings. They neither consider the difference of shape and the distance of the evaluation sequence of alternatives simultaneously nor deal with the interaction that universally exists among criteria. Furthermore, some enterprises cannot consult the best professional expert, which leads to inappropriate decisions. These reasons motivate us to contribute a novel hybrid MCDM technique called the grey fuzzy TOPSIS (FGT). It applies fuzzy measures and fuzzy integral to express and integrate the interaction among criteria, respectively. Fuzzy numbers are employed to help the experts to make more reasonable and accurate evaluations. The GCE method and the TOPSIS are combined to improve their one-sidedness. A case study of supplier evaluation of a collaborative manufacturing enterprise verifies the effectiveness of the hybrid method. The evaluation result of different methods shows that the proposed approach overcomes the shortcomings of GCE and TOPSIS. The proposed hybrid decision-making model provides a more accurate and reliable method for evaluating the fuzzy system MCDM problems with interaction criteria. [ABSTRACT FROM AUTHOR]

Leakage throughmicroscale or nanoscale cracks is usually hard to observe, difficult to control, and causes significant economic loss. In the present research, the leakage in a pipe was evaluated by the virtual entropy generation (VEG) method. In virtual entropy generation method, the "measured entropy generation" is forced to follow the "experimental second law of thermodynamics". Taking the leakage as the source virtual entropy generation, a new pipe leakage evaluation criterion was analytically derived, which indicates that the mass leakage rate should be smaller than the pressure drop rate inside a pipe. A numerical study based on computational fluid dynamics showed the existence of an unrealistic virtual entropy generation at a high mass leakage rate. Finally, the new criterion was used in the evaluation of leakage available in the literature. These results could be useful for leakage control or industry criteria design in the future. [ABSTRACT FROM AUTHOR]

The internal coupled electromagnetic melt treatment (ICEMT) method is firstly proposed to produce high-quality and large-sized aluminum alloy billets. A three-dimensional model was established to describe the ICEMT process of direct chill casting (DC casting). The effect of ICEMT on the fluid flow patterns and temperature field in the DC casting of ϕ880 mm AA2219 billets is numerically analyzed. Moreover, the mechanisms of the ICEMT process on grain refinement and macrosegregation were discussed. The calculated results indicate that the electromagnetic field appears to be coupled circinate at the cross section of the melt, the fluid flow becomes unstable accompanied by the bias flow, and the temperature profiles are significantly more uniform. An experimental verification was conducted and the results prove that compared with traditional direct chill casting, the microstructures of the AA2219 large-scale billet under the ICEMT process are uniform and fine. [ABSTRACT FROM AUTHOR]

The intertidal zone is a transitional area of the land-sea continuum, in which physical and chemical properties vary during the tidal cycle and highly toxic sulfides are rich in sediments due to the dynamic regimes. As a typical species thriving in this habitat, Urechis unicinctus presents strong sulfide tolerance and is expected to be a model species for sulfide stress research. Heat shock proteins (HSPs) consist of a large group of highly conserved molecular chaperones, which play important roles in stress responses. In this study, we systematically analyzed the composition and expression of HSPs in U. unicinctus. A total of eighty-six HSP genes from seven families were identified, in which two families, including sHSP and HSP70, showed moderate expansion, and this variation may be related to the benthic habitat of the intertidal zone. Furthermore, expression analysis revealed that almost all the HSP genes in U. unicinctus were significantly induced under sulfide stress, suggesting that they may be involved in sulfide stress response. Weighted gene co-expression network analysis (WGCNA) showed that 12 HSPs, including 5 sHSP and 4 HSP70 family genes, were highly correlated with the sulfide stress response which was distributed in steelblue and green modules. Our data indicate that HSPs, especially sHSP and HSP70 families, may play significant roles in response to sulfide stress in U. unicinctus. This systematic analysis provides valuable information for further understanding of the function of the HSP gene family for sulfide adaptation in U. unicinctus and contributes a better understanding of the species adaptation strategies of marine benthos in the intertidal zone. [ABSTRACT FROM AUTHOR]

Simple Summary: Foxl2 generally presents a sexually dimorphic expression pattern in animal gonads and is highly expressed in the ovary. However, few studies on the transcriptional regulation of Foxl2 have been documented. To understand the transcriptional regulating of Foxl2 high expression in the ovary, we used the Y1H system, a high throughput approach, for the first time to screen the transcription factors binding to the high transcriptional activity region of Foxl2 promoter in Zhikong scallop (Chlamys farreri) gonads. In the present study, the highly transcriptional activity promoter sequence of Cf-Foxl2 was determined at −1000~−616 bp and 11 candidate factors were verified to involve in Cf-Foxl2 transcriptional regulation. Our findings provided valuable data for better understanding the specific transcriptional regulation mechanism of Foxl2 in the ovary and would further assist in the breeding of aquacultural bivalves. Foxl2 is an evolutionarily conserved female sex gene, which is specifically expressed in the ovary and mainly involved in oogenesis and ovarian function maintenance. However, little is known about the mechanism that regulates Foxl2 specific expression during the ovary development. In the present study, we constructed the gonadal yeast one-hybrid (Y1H) library of Chlamysfarreri with ovaries and testes at different developmental stages using the Gateway technology. The library capacity was more than 1.36 × 107 CFU, and the length of the inserted fragment was 0.75 Kb~2 Kb, which fully met the demand of yeast library screening. The highly transcriptional activity promoter sequence of C. farreri Foxl2 (Cf-Foxl2) was determined at −1000~−616 bp by dual-luciferase reporter (DLR) assay and was used as bait to screen possible transcription factors from the Y1H library. Eleven candidate factors, including five unannotated factors, were selected based on Y1H as well as their expressional differences between ovaries and testes and were verified for the first time to be involved in the transcriptional regulation of Cf-Foxl2 by RT-qPCR and DLR. Our findings provided valuable data for further studying the specific regulation mechanism of Foxl2 in the ovary. [ABSTRACT FROM AUTHOR]

Armillaria species have a global distribution and play various roles in the natural ecosystems, e.g., pathogens, decomposers, and mycorrhizal associates. However, their taxonomic boundaries, speciation processes, and origin are poorly understood. Here, we used a phylogenetic approach with 358 samplings from Europe, East Asia, and North America to delimit the species boundaries and to discern the evolutionary forces underpinning divergence and evolution. Three species delimitation methods indicated multiple unrecognized phylogenetic species, and biological species recognition did not reflect the natural evolutionary relationships within Armillaria; for instance, biological species of A. mellea and D. tabescens are divergent and cryptic species/lineages exist associated with their geographic distributions in Europe, North America, and East Asia. While the species-rich and divergent Gallica superclade might represent three phylogenetic species (PS I, PS II, and A. nabsnona) that undergo speciation. The PS II contained four lineages with cryptic diversity associated with the geographic distribution. The genus Armillaria likely originated from East Asia around 21.8 Mya in early Miocene when Boreotropical flora (56–33.9 Mya) and the Bering land bridge might have facilitated transcontinental dispersal of Armillaria species. The Gallica superclade arose at 9.1 Mya and the concurrent vicariance events of Bering Strait opening and the uplift of the northern Tibetan plateau might be important factors in driving the lineage divergence. [ABSTRACT FROM AUTHOR]

The increasing proportion of unconventional worldwide energy demands have consistently promoted the necessity for exploring a precise, high-resolution, objective, and quantitative stratigraphic division method for macroscopically homogeneous mudstone successions. The chemostratigraphy can resolve this problem well, although it has been applied successfully in North America, but not systematically studied in China for shale gas exploration and development. This work has conducted a chemostratigraphic analysis of Wufeng and Longmaxi Formation on the Changning section of Sichuan Province, southwestern China, to testify its applicability for shale gas exploration in China. Principal component analysis (PCA) was first employed to reduce the dimensionality of datasets. Three chemofacies, including detrital (K, Ti, Fe, Al, Na, Mg, Cr, Zr, Rb), authigenic (Ca, Sr, Mn, Si, S, Ba), and redox-organic (P, V, Ni, Zn, Cu, TOC), were found. Subsequently, constrained clustering analysis was utilized for the zonation of each chemofacies into chemozones. Consequently, the whole Changning section was divided into twelve chemozones (CZ I–CZ Ⅻ). The geochemical interpretation for these chemozones can be resolved from the regional changes in paleogeography and paleoceanography during the Late Ordovician to Early Silurian period. Thus, a three-stage geochemical evolution along the Changning section can be classified: (1) the siliceous and anoxic deposits of Wufeng Formation (CZ I–CZ III) with high TOC contents; (2) the siliceous and anoxic sedimentary rocks of bottom Longmaxi Formation with still higher TOC (CZ Ⅳ); (3) the calcarous-detrital and oxic sediments for the rest of Longmaxi Formation (CZ Ⅴ–CZ Ⅻ). In considering their high content of TOC and abundant brittle siliceous minerals, the CZ (I–Ⅳ, 0 m–33.6 m) are thought to be the most preferable sweet spot for shale gas exploration. [ABSTRACT FROM AUTHOR]

The subsea observation network has become an indispensable means of ocean exploration worldwide. However, the scale of the subsea observation network is limited by the power supply voltage and power level. Hence, to promote the development of a subsea observation network, this paper investigates the underwater high voltage DC-DC converter (HVC), which greatly improves the voltage and power level of the subsea observation network. The traditional series-parallel converter based on multi-module is faced with many technical problems, such as difficult transformer isolation, many fault points, low power density under higher input voltage level, and higher output power. The subsea HVC of this paper adopts a modular multilevel resonant DC-DC converter. The main circuit of HVC is designed in detail, including a module circuit, a resonant circuit, and a control scheme. Through the combination of the sub-module removal voltage regulation and closed-loop control, the converter can still output a stable voltage of 375 V when the input voltage changes. The modular sub-module and centralized transformer structure enables the converter to isolate high voltage easily, small volume, and high power density. The simulation and experiment results show the proposed HVC meets the design requirements and has good application prospects. It can be applied to submarine power transmission and distribution needs because of its wide range, large transformation ratio, and high efficiency. [ABSTRACT FROM AUTHOR]

The high-volume fraction SiC/Al composite is the new type of electronic packaging material, which plays an important role in the field of high-power integrated circuits. In this study, SiC/Al composites with high-volume fraction of SiC particles were prepared by vacuum pressure infiltration. The influence of SiC particle size and NH4HCO3 on the pores in the preform was explored, aiming to accurately adjust the volume fraction of SiC to meet the thermal performance requirements in different fields. In addition, the preform was infiltrated with different Al alloys, and the relationship between the porosity and thermal conductivity of SiC/Al was studied. For the SiC preform, the volume fraction of SiC can be adjusted regularly when 12 μm and 100 μm SiC particles are mixed in different proportions, and the volume fraction reaches the maximum when the proportion of coarse particles is about 77%. NH4HCO3 is conducive to the connectivity of pores in the preform, and about 40 vol.% of NH4HCO3 can effectively increase the porosity of the preform. Thermal conductivity is sensitive to the porosity of composites, especially in the range of 2.5–4.5%. A simple application of the Hasselman–Johnson model and a new thermal conductivity model, λd, established in this article, offer a good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

The effect of high pressure on the microstructure of hypo-peritectic Al–38wt.%Ni alloy was studied. The results show that Al3Ni and Al3Ni2 phases coexist at ambient pressure. However, it becomes a typical hyper-eutectic microstructure when synthesized at 2 GPa and 4 GPa. Meanwhile, the interface temperature of Al3Ni and Al3Ni2 phases was calculated with the combination of the BCT dendrite growth model, which is suitable for the Al3Ni2 phase. According to the highest interface temperature principle, the result shows that the Al3Ni phase dominates over 1–5 GPa. Finally, the Debye temperature and potential energy of the hypo-peritectic Al–38wt.%Ni alloy under different pressures were researched. Based on the low temperature specific heat-capacity curve. The Debye temperatures at ambient pressure, 2 GPa, and 4 GPa are 504.4 K, 508.71 K and 515.36 K, respectively, and the potential energy in the lowest point decreases with the increase of pressure. [ABSTRACT FROM AUTHOR]

As a consequence of recent progression in biomedicine and nanotechnology, nanoparticle-based systems have evolved as a new method with extensive applications in responsive therapy, multimodal imaging, drug delivery and natural product separation. Meanwhile, the magnetic nanoparticulate system has aroused great interest for separation and purification because of its excellent magnetic properties. Phospholipase A2 (PLA2) is a highly expressed regulator to promote the growth of various cancers and is an ideal target to treat cancers. In this study, a novel strategy based on ligand–receptor interactions to discover novel PLA2 inhibitors was established, in which PLA2-functionalized Fe3O4@PLGA-PEG-NH2 magnetic nanoparticles were used as a supporting material combined with high-performance liquid chromatography–mass spectrometry, aiming to accelerate the discovery of novel PLA2 inhibitors from natural sources such as mangrove endophytic fungi. Under the optimized ligand fishing conditions, six target compounds were ultimately fished and identified to be cyclic peptides (1–3) and sterols (4–6), which compounds 1, 2 and 4–6 have well-documented cytotoxicities. Compound 3 exerted better inhibitory effect on A549 cells by experiment. In conclusion, PLA2-functionalized Fe3O4@PLGA-PEG-NH2 magnetic nanoparticles-based ligand fishing provided a feasible, selective and effective platform for the efficient screening and identification of antitumor components from natural products. [ABSTRACT FROM AUTHOR]

The requirements of high-strength, wear-resistance and lightweight of brake drums have been continually increasing in recent years and any specific aluminum alloy or particle-reinforced aluminum matrix composites may not satisfy all the demands. Combining dissimilar materials to play their respective advantages is a solution to this problem. In this study, a compound casting method was used to combine solid SiCp/A357 composite and a liquid 7050 aluminum alloy to prepare an aluminum matrix composite with a layered structure. The ProCAST numerical simulation software was used to predict the heat transfer in compound casting process and guide the preheating temperature of the wear-resistant ring in the experiment. An Optical Microscope (OM) and Scanning Electron Microscope (SEM) were used to observe microstructures around the solid–liquid bonding interface, the element distribution and phase component of which were analyzed by Energy Dispersive Spectroscopy (EDS) and mechanical properties were evaluated by microhardness and shear tests. The results showed that the interface of the layered aluminum matrix composite prepared by this method achieved complete metallurgical bonding and a transition zone formed on the solid surface. After T6 heat treatment, the average shear strength of the interface increased from 19.8 MPa to 33.8 MPa. [ABSTRACT FROM AUTHOR]

In this study, large-sized Al–Zn–Mg–Cu alloy billets were prepared by direct chill casting imposed with annular electromagnetic stirring and intercooling; a process named uniform direct chill casting. The effects of uniform direct chill casting on grain size and the alloying element distribution of the billets were investigated and compared with those of the normal direct chill casting method. The results show that the microstructures were refined and the homogeneity of the alloying elements distribution was greatly improved by imposing the annular electromagnetic stirring and intercooling. In uniform direct chill casting, explosive nucleation can be triggered, originating from the mold wall and dendrite fragments for grain refinement. The effects of electromagnetic stirring on macrosegregation are discussed with consideration of the centrifugal force that drives the movement of melt from the central part towards the upper-periphery part, which could suppress the macrosegregation of alloying elements. The refined grain can reduce the permeability of the melt in the mushy zone that can restrain macrosegregation. [ABSTRACT FROM AUTHOR]

High-strength aluminum alloy (mainly refers to the 7xxx series) is the optimum material for lightweight military equipment. However, this type of aluminum alloy is a wrought aluminum alloy. If it is directly formed by traditional casting methods, there will inevitably be problems such as coarseness, unevenness, looseness, and hot cracking in the structure, which will greatly affect the final performance of the part. Based on the internal cooling with annular electromagnetic stirring (IC-AEMS) method, a new technology of rheological die forging is developed in this paper, and the scale-reduced parts of a brake hub of Al-6.54Zn-2.40Cu-2.35Mg-0.10Zr aluminum alloy were prepared. The influence of IC-AEMS and the addition of rare element Sc on the structure and mechanical properties of the parts was studied. An optical microscope and scanning electron microscope (SEM) were used to observe the microstructure evolution, energy dispersive spectroscopy (EDS) was used to analyze the phase distribution and composition, and the mechanical properties of the parts were tested by uniaxial tensile tests. The results show that the addition of Sc element can effectively refine the grains and improve the strength and elongation of the material; the application of IC-AEMS improves the cooling rate of the melt, increases the effective nucleation rate, and the grains are further refined. Through process optimization, scale-reduced parts of a brake hub with good formability and mechanical properties can be obtained, the ultimate tensile strength is 597.2 ± 3.1 MPa, the yield strength is 517.8 ± 4.3 MPa, and the elongation is 13.7 ± 1.3%. [ABSTRACT FROM AUTHOR]

The discovery of new active compounds of natural products tends to be increasingly more challenging due to chemical complexity and unpredictable matrices. Forskolin is an active natural labdane-type diterpenoid ingredient widely used worldwide for the treatment of glaucoma, heart failure, hypertension, diabetes, and asthma, and is expected to be a promising anticancer, anti-inflammation, and anti-HIV agent. In recent years, demand for forskolin in the medicine market has increased dramatically. However, natural forskolin originates exclusively from traditional Indian herb medicine Coleus forskohlii (Willd.) Briq. In a previous study, we isolated a series of diterpenoids including an 8,13-epoxy-14ene labdane carbon skeleton from Blumea aromatica DC. In order to identify alternative plant resources, a novel and effective strategy was proposed for the screening of potential forskolin-type diterpenoids (FSKD) compounds obtained from B. aromatica, using the mass defect filtering (MDF) strategy via ultra-high-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UHPLC-QTOF/MS) approach. Within a narrow, well-defined mass defect range, the strategy developed could significantly improve the detection efficiency of selected FSKD compounds by filtering out certain major or moderate interference compounds. Additionally, the MS/MS cleavage behavior and the characteristic diagnostic ions of the FSKD compounds were proposed to be used in aiding structural identification of the filtration compounds. As a result, a total of 38 FSKD of B. aromatica were filtered out and tentatively identified. To the best of our knowledge, it was the first time that these forskolin-type diterpenoids were identified in B. aromatica, which significantly expands our understanding of the chemical constituents of Blumea species, and allows B. aromatica to be used as a potential alternative plant resource that contains these forskolin-type active compounds. The strategy proposed was proven efficient and reliable for the discovery of novel compounds of herbal extracts. [ABSTRACT FROM AUTHOR]

Notopterygium franchetii is a herb used in traditional Chinese medicine, where it is known as qianghuo. Its bioactive qualities are influenced by the post-harvest processing methods used (such as drying). However, changes in chemical components according to the drying method are unknown. Fresh roots and rhizomes of N. franchetii were subjected to seven drying methods. Chromatography-mass spectrometry combined with targeted and untargeted analyses were used to investigate relationships between drying methods and chemical concentrations. According to targeted evaluations of the six main bioactive constituents, their total contents decreased significantly in all drying methods. Hierarchical clustering analysis of the drying methods and total metabolome detected 30 chemical constituents, for which heap maps were obtained. Hot air drying was the best processing method, producing the least chemical changes at the lowest cost, while shade drying caused the greatest chemical changes. In conclusion, the wide range of chemical changes in N. franchetii caused by drying was investigated. Such changes potentially affect the quality of herbal medicines. [ABSTRACT FROM AUTHOR]

There are two critical stages of grain refinement during solidification: above and below the liquidus temperature. The key to improve the refinement potential is ensuring the nucleation sites precipitate in large quantities and dispersed in the melt above liquidus. In this work, internal cooling with annular electromagnetic stirring was applied to an Al-Zn-Mg-Cu-Zr alloy at a temperature above liquidus. A systematic experimental study on the grain refining potential was performed by combining different melt treatments and pouring temperatures. The results indicate that internal cooling with annular electromagnetic stirring (IC-AEMS) had a significantly superior grain refining potency for the alloy compared to traditional electromagnetic stirring (EMS). In addition, homogeneous and refined grains were achieved at high pouring temperatures with IC-AEMS. The possible mechanisms for the enhanced grain refinement above the liquidus temperature are explained as the stable chilling layer around the cooling rod in IC-AEMS providing undercooling for the precipitation of Al3Zr nucleant particles and the high cooling rate restraining the growth rate of these particles. At the same time, forced convection promotes a more homogeneous distribution of nucleant particles. [ABSTRACT FROM AUTHOR]

A new type of inhibitor is studied in this paper. Inhibition efficiency and adsorption behavior of an inhibitor film on the steel surface is tested via the electrochemical method and theoretical calculation to establish the adsorption model. Test results confirm that inhibition efficiency is improved with the addition of an inhibitor, and the inhibitor film is formed firmly by comparing the characteristic peaks of S and N. Moreover, the micro-zone corrosion progress of Fe in 3.5% invasive NaCl-simulated seawater environment is studied. The results further show that corrosion is initiated under the zone without the inhibitor film, while it is prevented under the protection of the film. By the experiments, it is shown that inhibitor can be adsorbed on the surface of steel stably and has excellent protection performance for reinforced rebar, which can be widely used in concrete structure. [ABSTRACT FROM AUTHOR]

The larval segment formation and secondary loss in echiurans is a special phenomenon, which is considered to be one of the important characteristics in the evolutionary relationship between the Echiura and Annelida. To better understand the molecular mechanism of this phenomenon, we revealed the larval transcriptome profile of the echiuran worm Urechis unicinctus using RNA-Seq technology. Twelve cDNA libraries of U. unicinctus larvae, late-trochophore (LT), early-segmentation larva (ES), segmentation larva (SL), and worm-shaped larva (WL) were constructed. Totally 243,381 unigenes were assembled with an average length of 1125 bp and N50 of 1836 bp, and 149,488 unigenes (61.42%) were annotated. We obtained 70,517 differentially expressed genes (DEGs) by pairwise comparison of the larval transcriptome data at different developmental stages and clustered them into 20 gene expression profiles using STEM software. Based on the typical profiles during the larval segment formation and secondary loss, eight signaling pathways were enriched, and five of which, mTOR, PI3K-AKT, TGF-β, MAPK, and Dorso-ventral axis formation signaling pathway, were proposed for the first time to be involved in the segment formation. Furthermore, we identified 119 unigenes related to the segment formation of annelids, arthropods, and chordates, in which 101 genes were identified in Drosophila and annelids. The function of most segment polarity gene homologs (hedgehog, wingless, engrailed, etc.) was conserved in echiurans, annelids, and arthropods based on their expression profiles, while the gap and pair-rule gene homologs were not. Finally, we verified that strong positive signals of Hedgehog were indeed located on the boundary of larval segments using immunofluorescence. Data in this study provide molecular evidence for the understanding of larval segment development in echiurans and may serve as a blueprint for segmented ancestors in future research. [ABSTRACT FROM AUTHOR]

This study presents a modified annular electromagnetic stirring (M-AEMS) melt treatment suitable for a large-volume and high-alloyed aluminum alloy. A 3D computational model coupling an electromagnetic model with a macroscopic heat and fluid-flow model was established by using Ansoft Maxwell 3D and Fluent from ANSYS workbench, and the effects of the electromagnetic shielding ring, the height of the magnet yoke, the shape of the iron core, and the internal cooling mandrel on the electromagnetic, thermal and flow fields were studied numerically. Based on the optimal technical parameters, the effectivity of the M-AEMS process by using 7075 alloy was validated experimentally. The results show that a favorable electromagnetic field distribution can be achieved by changing the magnet yoke height, the iron-core shape and the electromagnetic shielding ring, and the melt temperature of the 7075 alloy can drop rapidly to the pouring temperature by imposing the internal cooling mandrel; compared with ordinary annular electromagnetic stirring, the M-AEMS process creates a lower magnetic strength near the melt top, beneficial for stabilizing the melt surface; meanwhile, it yields a higher magnetic strength near the melt bottom, which increases the shear rate and ensures an optimal stirring effect. Therefore, M-AEMS works more efficiently because the thermal and composition fields become uniform in a shorter time, which reduces the average grain size and the composition segregation, and a more stable melt surface can be obtained during treatment, which reduces the number of air and oxide inclusions in the melt. [ABSTRACT FROM AUTHOR]