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Plant specialization and pollination network structure play important roles in community assembly. Floral traits can mediate plant–pollinator interactions and thus have important impacts on nestedness and modularity of pollination network. When such traits are phylogenetically conserved, therefore, phylogeny and traits should predict network structure to similar degrees. Moreover, conserved network structures were also found attributed to pollination syndrome or pollination system. However, we still know little about the relation between pollination syndrome and pollination network, especially under a phylogenetic framework. Herein, we established a phylogenetic framework including five floral traits (flower density, floral size, floral shape, floral symmetry, and floral color) and five species-level metrics (species strength, weighted closeness, specialization d’, nestedness contribution, and modularity contribution) to test how floral traits could directly or indirectly influence species’ specialization and network structure in central China. Phylogenetic signals were found in all floral traits except flower density. Structural equation model and phylogenetic structural equation model results showed that both floral size and floral density affected plant specialization and its contribution to network modularity indirectly. However, compared with phylogenetic independent flower density, phylogenetic conserved floral size had much more complexed influences, having a direct influence both on species’ specialization and on modularity contribution. In this nested and modular network, abundant species with larger flowers tend to be more central and had larger values of z. Floral shape, symmetry, and color could act as co-flowering filters in pollination sharing and help to shape network modularity. Our results emphasize that phylogenetically conserved traits partially represent pollination syndrome and are important drivers for modular structure of local pollination network. This study may improve the understanding how the evolutionary history and ecological process drive local network structure and dynamics.

Lubricant additive plays an important role in reducing the friction and wear for base oil. MAX phase ceramics may have superior advantages for additive application due to their unique nanolayered structure. In this paper, Ti2SnC ceramic is prepared by sintering the elemental mixtures at 1250 °C. In addition, Cu-coated Ti2SnC ceramic is successfully prepared using a chemical plating method for the first time. It is confirmed that the Ti2SnC ceramic has good self-catalytic activity, and a layer of stacking Cu nano-particles can be deposited on the Ti2SnC surface without pretreatment. When the Cu-coated Ti2SnC ceramic powder is doped into PAO10 base oil, the oil can exhibit excellent lubrication properties, where the friction coefficient is as low as 0.095. A layer of tribo-film can be formed during the sliding process when the Cu-coated Ti2SnC ceramic is incorporated into PAO10 base oil, which can reduce the friction coefficient. The superior lubrication properties can be attributed to the synergistic lubrication effect of Ti2SnC ceramic and Cu nano-particles.

Batocera horsfieldi (Hope) (Coleoptera: Cerambycidae) is an important forest pest in China that mainly infests timber and economic forests. This pest primarily causes plant tissue to necrotize, rot, and eventually die by feeding on the woody parts of tree trunks. To gain a deeper understanding of the genetic mechanism of B. horsfieldi, this study employed single-molecule real-time sequencing (SMRT) and Illumina RNA-seq technologies to conduct full-length transcriptome sequencing of the insect. Total RNA extracted from male and female adults was mixed and subjected to SMRT sequencing, generating a complete transcriptome. Transcriptome analysis, prediction of long non-coding RNA (lncRNA), coding sequences (CDs), analysis of simple sequence repeats (SSR), prediction of transcription factors, and functional annotation of transcripts were performed in this study. The collective 20,356,793 subreads (38.26 G, clean reads) were generated, including 432,091 circular consensus sequences and 395,851 full-length non-chimera reads. The full-length non-chimera reads (FLNC) were clustered and redundancies were removed, resulting in 39,912 consensus reads. SSR and ANGEL software v3.0 were used for predicting SSR and CDs. In addition, four tools were used for annotating 6058 lncRNAs, identifying 636 transcription factors. Furthermore, a total of 84,650 transcripts were functionally annotated in seven different databases. This is the first time that the full-length transcriptome of B. horsfieldi has been obtained using SMRT sequencing. This provides an important foundation for investigating the gene regulation underlying the interaction between B. horsfieldi and its host plants through gene editing in the future and provides a scientific basis for the prevention and control of B. horsfieldi.

Titanium alloy is an important material for the manufacture of key components of deep-sea submersibles. High-power vacuum laser welding is an important method for welding TC4 thick plate (40–120 mm) structures. However, due to the low melting point of aluminum, its uneven distribution in the weld caused by evaporation during welding affects the quality of joints. This paper conducted experimental and simulation studies to investigate the effect of process parameters on multi-component evaporation and uneven aluminum distribution. Based on a three-dimensional model of vacuum laser welding, the mechanism of the uneven distribution of aluminum in the weld is explained. The results show that the uneven distribution of aluminum in the weld is mainly related to the metal vapor behavior and keyhole morphology. As the welding speed rises from 1 m/min to 3 m/min, the proportion of aluminum in the metal vapor and the degree of compositional unevenness increase. When the laser power increases from 6 kW to 18 kW, the proportion of aluminum in the metal vapor and degree of unevenness increase, peak at 12 kW, and then decrease. This work facilitates the selection of suitable process parameters to reduce aluminum evaporation during the high-power vacuum welding of Ti-6Al-4V alloys. Joints with a more stable performance can be obtained by avoiding the uneven distribution of aluminum.

Glucosinolates (GSLs) are important secondary metabolites that play important defensive roles in cruciferous plants. Chinese flowering cabbage, one of the most common vegetable crops, is rich in GSLs and thus has the potential to reduce the risk of cancer in humans. Many genes that are involved in GSL biosynthesis and metabolism have been identified in the model plant Arabidopsis thaliana; however, few studies investigated the genes related to GSL biosynthesis and metabolism in Chinese flowering cabbage. In the present study, the GSL composition and content in three different organs of Chinese flowering cabbage (leaf, stalk, and flower bud) were determined. Our results showed that the total GSL content in flower buds was significantly higher than in stalks and leaves, and aliphatic GSLs were the most abundant GSL type. To understand the molecular mechanisms underlying the variations of GSL content, we analyzed the expression of genes encoding enzymes involved in GSL biosynthesis and transport in different tissues of Chinese flowering cabbage using RNA sequencing; the expression levels of most genes were found to be consistent with the pattern of total GSL content. Correlation and consistency analysis of differentially expressed genes from different organs with the GSL content revealed that seven genes (Bra029966, Bra012640, Bra016787, Bra011761, Bra006830, Bra011759, and Bra029248) were positively correlated with GSL content. These findings provide a molecular basis for further elucidating GSL biosynthesis and transport in Chinese flowering cabbage.

The hot deformation behavior of TiAl alloy is analyzed by combining the true stress–strain curve and microstructure analysis. The results show that the flow stress of TiAl alloy presents the characteristics of work hardening-dynamic softening, it increases with the increase of strain rate and decreases with the increase of temperature. Based on the true stress–strain curves, the flow stress of TiAl alloy under different deformation conditions is predicted by hyperbolic sinusoidal formula. In addition, the effects of deformation temperature and strain rate on the microstructure evolution of TiAl alloy are revealed. In the process of hot compression deformation, dynamic recrystallization and γ → α , β → α phase transformation occurs. During tensile deformation, TiAl alloy exhibits super-plasticity, which is mainly due to grain rotation and coordinated deformation of β phase.

Milk is a rich source of lipids, with the major components being triglycerides (TAG) and phospholipids (mainly phosphatidylcholine (PC), sphingomyelin (SM), phosphatidylethanolamine (PE), phosphatidylserine (PS) and phosphatidylinositol (PI)). Liquid chromatography-mass spectrometry (LC-MS) is the predominant technique for lipid identification and quantification across all biological samples. While fatty acid (FA) composition of the major lipid classes of milk can be readily determined using tandem MS, elucidating the regio-distribution and double bond position of the FA remains difficult. Various workflows have been reported on the quantification of lipid species in biological samples in the past 20 years, but no standard or consensus methods are currently available for the quantification of milk phospholipids. This study will examine the influence of several common factors in lipid analysis workflow (including lipid extraction protocols, LC stationary phases, mobile phase buffers, gradient elution programmes, mass analyser resolution and isotope correction) on the quantification outcome of bovine milk phospholipids. The pros and cons of the current LC-MS methods as well as the critical problems to be solved will also be discussed.

An accurate dry matter intake (DMI) measurement method is of great importance for determining the performance of dairy cows. While n-alkane technique is commonly used to estimate the DMI of ruminants, the protocols used to measure alkanes are complex, time consuming and low throughput. Herein we present a simplified and miniaturised protocol that combines a smaller sample matrix (60 mg of faeces or herbage), a shorter (3 h) saponification step and a direct purification of the crude extract by filtration through silica powder or mixing with silica powder prior to GC-FID analysis. In addition to a much higher throughput compared with the existing methods, by skipping the commercial SPE columns and reducing the organic solvent volume, our miniaturised protocol should significantly reduce the sample processing cost and is thus suitable for alkane determination for large-scale experiments.

Cross-linked polyethylene (XLPE) has been widely used as insulation material for cables. In 2019, the highest voltage level AC 500 kV XLPE submarine cable has been operated in Zhoushan, China. The irreversible degradation poses a safety hazard to the operation of submarine cable. Therefore, it is necessary to investigate the physical, chemical and electrical properties of XLPE submarine cable insulation under aging condition and explore the method for its deterioration degree assessment. In this paper, the AC 500 kV XLPE submarine cable insulation material was thermally aged at 130 °C. The deterioration characteristics of materials were analyzed based on morphology, chemical structure, mechanical property, thermal property and dielectric properties. Multiple characteristic parameters were extracted and new deterioration condition assessment model was established. Results show that the physicochemical characteristic parameters including retention rate of elongation at break, carbonyl index (CI) based on FTIR, full-width at half-maximum (FWHM) of the diffraction peak based on XRD, melting enthalpy based on DSC analysis, and the dielectric characteristic parameters including modified Cole-Cole model parameter χsα and AC breakdown strength are sensitive to deterioration condition of XLPE material. According to the change of elongation retention at break, the deterioration condition of XLPE sample was divided into enhanced stage, wear-out stage and disposal stage. The new multi-factor deterioration condition assessment model including six characteristic parameters (retention rate of elongation at break, CI, FWHM, melting enthalpy, modified Cole-Cole model parameter χsα, AC breakdown strength) was successfully established by grey correlation analysis. The new model can reflect the property of mechanical, chemical, thermal and dielectric property and has prominent effect in differentiating deterioration degree of the AC 500 kV XLPE submarine cable insulation material.

Titanium and its alloys have excellent combination of properties, such as low density, high specific strength and corrosion resistance, and they are extensively used in many industrial fields. This work is aiming at investigation on the microstructure and mechanical properties of Ti–6Al–3Nb–2Zr–1Mo (Ti6321) alloy joints by Electron beam welding (EBW). The results show that the microstructure of the weld metal (WM) is composed of a mixture of acicular α, acicular α′, and β. The heat affected zone (HAZ) near WM consists of acicular α, primary α, acicular β phase and lots of acicular martensite α′. The HAZ near base metal consists of primary α phase and transformed β containing acicular α. The micro-hardness of the weld metal and heat affected zone are higher than that of base metal, and there are the peak values for the HAZ near the weld metal. The tensile strength of joint is equal to that of base metal, and the fracture locations of all the tensile specimens are in base metal, and it is well in accordance with the relationship between microstructure and mechanical properties of welded joints. Keywords: Ti6321, Electron beam welding, Microstructure, Properties

Short-chain fatty acids (SCFA, C2-C5) in milk and serum are derived from rumen bacterial fermentation and, thus, have the potential to be used as biomarkers for the health status of dairy cows. Currently, there is no comprehensive and validated method that can be used to analyse all SCFAs in both bovine serum and milk. This paper reports an optimised protocol, combining 3-nitrophenylhydrazine (3-NPH) derivatisation and liquid chromatography-mass spectrometry (LC-MS) analysis for quantification of SCFA and β-hydroxybutyric acid (BHBA) in both bovine milk and bovine serum. This method is sensitive (limit of detection (LOD) ≤ 0.1 µmol/L of bovine milk and serum), accurate (recovery 84–115% for most analytes) and reproducible (relative standard deviation (RSD) for repeated analyses below 7% for most measurements) with a short sample preparation step. The application of this method to samples collected from a small cohort of animals allowed us to reveal a large variation in SCFA concentration between serum and milk and across different animals as well as the strong correlation of some SCFAs between milk and serum samples.

Transgene-based genetic sexing methods are being developed for insects of agricultural and public health importance. Male-only rearing has long been sought in sericulture because males show superior economic characteristics, such as better fitness, lower food consumption, and higher silk yield. Here we report the establishment of a transgene-based genetic sexing system for the silkworm, Bombyx mori. We developed a construct in which a positive feedback loop regulated by sex-specific alternative splicing leads to high-level expression of the tetracycline-repressible transactivator in females only. Transgenic animals show female-specific lethality during embryonic and early larval stages, leading to male-only cocoons. This transgene-based female-specific lethal system not only has wide application in sericulture, but also has great potential in lepidopteran pest control. [ABSTRACT FROM AUTHOR]

Regioisomers (or positional isomers) of triacylglycerols (TAGs) of milk are known to show differential outcome in relation to human absorption. Quantitation of TAG regioisomers remains a big challenge due to the lack of facile chromatographic separation technique. The feasibility of using fragment ion intensity ratio to determine the ratio of co-eluting AAB/ABA-type regioisomer pairs was confirmed in this study. The ability of C30 stationary phase in resolving interfering TAG isomers was demonstrated for the first time. This allowed us to reveal the complexity of using fragment ion intensity to quantify 1,2-olein-3-palmitin (OOP), 1,3-olein-2-palmitin (OPO), 1,2-olein-3-stearin (OOS), and 1,3-olein-2-stearin (OSO) regioisomers in milk samples. A novel algorithm was proposed to consider the contribution of OPO/OOP and OSO/OOS double bond (DB)-isomers and to eliminate the interference of isobaric ions from other isomers, an aspect overlooked in previous studies. This liquid chromatography-mass spectrometry method that requires no pre-fractioning and a moderate chromatographic separation time of 36 min is simple and, thus, suitable for screening a large number of samples for genetic analysis of this trait. Preliminary results using a small cohort of animals showed that OPO/OOP ratio differs significantly between Jersey and Holstein cows, and a large variation was also observed across individual Holstein cows.

Abstract Background The diacylhydrazine derivatives have attracted considerable attention in recently years due to their simple structure, low toxicity, and high insecticidal selectivity. As well as 3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole is an important scaffold in many insecticidal molecules. In an effort to discover new molecules with good insecticidal activity, a series of diacylhydrazine derivatives containing a 3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole scaffold was synthesized and bio-assayed. Results Bioassays demonstrated that some of the title compounds exhibited favorable insecticidal activities against Helicoverpa armigera and Plutella xylostella. The insecticidal activity of compounds 10g, 10h, and 10w against H. armigera were 70.8, 87.5, and 79.2%, respectively. Compounds 10c, 10e, 10g, 10h, 10i, 10j and 10w showed good larvicidal activity against P. xylostella. In particular, the LC50 values of compounds 10g, 10h, and 10w were 27.49, 23.67, and 28.90 mg L−1, respectively. Conclusions A series of diacylhydrazine derivatives containing a 3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole scaffold was synthesized and bio-assayed. The results of insecticidal tests revealed that the synthesized diacylhydrazine derivatives possessed weak to good insecticidal activities against H. armigera and P. xylostella. Compounds 10g, 10h, and 10x showed much higher insecticidal activity than tebufenozide, and exhibited considerable prospects for further optimization. Primary structure–activity relationship revealed that phenyl, 4-fluoro phenyl and four fluorophenyl showed positive influence on their insecticidal activities, and introduction of a heterocyclic ring (pyridine and pyrazole) showed negative impacts on their insecticidal effects.

Volatile phenols (VPs) derived from smoke-exposed grapes are known to confer a smoky flavor to wine. Current methods for determination of VPs in grape berries either involve complex sample purification/derivatization steps or employ two analytical platforms for free and bound VP fractions. We report here a simple gas chromatography-tandem mass spectrometry (GC-MS/MS) method for quantification of both free and bound VPs in grapes, based on optimized (1) GC-MS/MS parameters, (2) an analyte extraction procedure, and (3) phenol glycoside hydrolysis conditions. Requiring neither sample cleanup nor a derivatization step, this method is sensitive (LOD ≤ 1 ng/g berries) and reproducible (RSD < 12% for repeated analyses) and is expected to significantly reduce the sample turnover time for smoke taint detection in vineyards.

A series of caffeic acid amides were designed, synthesized and evaluated for anti-inflammatory activity. Most of them exhibited promising anti-inflammatory activity against nitric oxide (NO) generation in murine macrophage RAW264.7 cells. A 3D pharmacophore model was created based on the biological results for further structural optimization. Moreover, predication of the potential targets was also carried out by the PharmMapper server. These amide analogues represent a promising class of anti-inflammatory scaffold for further exploration and target identification.

Ensuring the large signal stability of the DC microgrid is the premise of the safe operation of the DC microgrid, but the research on the large-signal stability of microgrids with multiple droop control micro-sources is still scarce. In this paper, a DC microgrid system model with multiple droop control micro-sources was established by appropriate simplification. Addressing the problem that most stability research methods cannot be quantitatively analyzed, the mixed potential function method was used to analyze the large signal stability of the system. However, the criterion obtained by the conventional mixed potential function method is complicated and contains multiple time-varying parameters, which is not convenient for analysis. Therefore, the simple form of the criterion was obtained through simplification and the analysis proved the rationality of the simplification. On this basis, a nonlinear droop control method was proposed to improve the anti-interference ability of the system. Finally, the accuracy of the large signal stability criterion and the effectiveness of nonlinear droop control on the system’s large signal stability were verified by simulation.

Glutathione conjugation reactions are one of the principal mechanisms that plants utilize to detoxify xenobiotics. The induction by four herbicides (2,4-D, atrazine, metolachlor and primisulfuron) and a herbicide safener (dichlormid) on the expression of three genes, ZmGST27, ZmGT1 and ZmMRP1, encoding respectively a glutathione-S-transferase, a glutathione transporter and an ATP-binding cassette (ABC) transporter was studied in maize. The results demonstrate that the inducing effect on gene expression varies with both chemicals and genes. The expression of ZmGST27 and ZmMRP1 was up-regulated by all five compounds, whereas that of ZmGT1 was increased by atrazine, metolachlor, primisulfuron and dichlormid, but not by 2,4-D. For all chemicals, the inducing effect was first detected on ZmGST27. The finding that ZmGT1 is activated alongside ZmGST27 and ZmMRP1 suggests that glutathione transporters are an important component in the xenobiotic detoxification system of plants.

The metabolism of chiral herbicides in plants remains poorly understood. Glutathione conjugation reactions are one of the principal mechanisms that plants utilize to detoxify xenobiotics. The induction by rac- and S-metolachlor of the expression of three genes, ZmGST27, ZmGT1 and ZmMRP1, encoding respectively a glutathione-S-transferase, a glutathione transporter and an ATP-binding cassette (ABC) transporter was studied in maize. The results demonstrate that the inducing effect of rac- and S-metolachlor on the expression of ZmGST27 and ZmGT1 is comparable. However, the inducing effect of rac-metolachlor on ZmMRP1 expression is more pronounced than that of S-metolachlor. Furthermore, vanadate, an ABC transporter inhibitor, could greatly reduce the difference in herbicidal activity between rac- and S-metolachlor. These results suggest that the ABC transporters may preferentially transport conjugates of rac-metolachlor, leading to a faster metabolism of the latter. Through comparing the expression of ZmGST27, ZmMRP1 and ZmGT1 after treatment by rac- and S-metolachlor, we provide novel insights into the metabolic processes of chiral herbicides in plants.

Objective: To summarize the ultrasonographic characteristics of testicular adrenal tumor (TART) in male patients with congenital adrenocortical hyperplasia (CAH) due to 21-hydroxylase deficiency, and to improve the understanding of sonographers on TART. Methods: Twenty-one CAH patients due to 21-hydroxylase deficiency were collected. All patients were found to have abnormal echoes in the testis by scrotal high-frequency ultrasound examination and were diagnosed as TART. The ultrasonic images of TART lesions were observed, and the number and growth mode of the lesions involving the testis were evaluated. The morphology, boundary, echogenicity and blood supply characteristics, and epididymis involvement were observed. Results: Among the 21 patients, 14 patients had bilateral testicular lesions with the same ultrasound features, and seven patients were unilateral. Two patients were epididymal involvement. Among the total 35 testicular lesions, 82.9% (29/35) grew along the testicular mediastinum, 17.1% (6/35) grew diffusely. Hypoechoic lesions accounted for 51.4% (18/35), heterogeneous hyperechoic lesions accounted for 28.6% (10/35), and heterogeneous hyperechoic lesions with coarse calcification accounted for 20%(7/35). The lesion morphology mainly showed irregular lobular shape and round shape, accounting for 85.7% (30/35) and 14.3% (7/35), respectively. The rich blood supply lesions accounted for 62.8% (22/35), and 22.9% (8/35) and 14.3% (5/35) of the lesions were hypovascular or anvascular. Conclusions: Sonographic appearance of TART is variable but still characteristic. The lesions present as bilateral testis with rich blood supply and irregular hypoechoic growth along the mediastinum. The ultrasonic features of the bilateral lesions are the same. With the history of CAH, it might provide clues for diagnosis of TART.