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Herein, we report two tetranuclear lanthanide complexes, of which the Dy4-complex exhibits significant single-molecule magnetic properties with the open hysteresis loop is detected until 6.5 K and a coercive field of 453 Oe is observed at 1.8 K.

We review the recent research progress of multifunctional lanthanide-based single-molecule magnets exhibiting luminescence thermometry and photochromic and ferroelectric properties, as well as the synergistic effect between them.

A series of di- and tetranuclear lanthanide complexes with the formulas [Dy

Purpose Microbial resources are abundant in fermented grains of the Chinese Fen-flavor Baijiu, which is closely related to the quality of Baijiu. The purpose of this study was to investigate the microbial community structure and function in Daqu and fermented grains. Methods We systematically compared two technical approaches, amplicon sequencing, and metagenomic sequencing, to analyze the microbial communities during Baijiu fermentation. Result The results showed that lactic acid bacteria (LAB) and yeasts were the main microorganisms in the fermentation process. Firmicutes (Lactobacillus, Pediococcus, and Weissella) were the dominant bacteria, and Ascomycota (Issatchenkia or Pichia) was the dominant fungus in fermented grains. Moreover, Pichia kudriavzevii, Lichtheimia ramosa, and Companilactobacillus paralimentarius were the dominant species at the initial stage of fermentation by metagenomic sequencing. Latilactobacillus curvatus, Loigolactobacillus coryniformis subsp. coryniformis, and Lentilactobacillus parabuchneri became dominant during the middle stage of fermentation. Lentilactobacillus parabuchneri and Lactobacillus acetotolerans were the dominant species in the final stage of fermentation. Spearman correlation analysis showed that LAB inhibited the growth of yeasts. Conclusion Combining the two sequencing methods provided valuable insights into the dynamic succession of microorganisms during the fermentation of Baijiu. It had had a particular significance for mining microbial species resources in fermented grains.

Two 42-nuclearity lanthanide complexes with a wheel-like structure were synthesized, in which Gd congeners exhibited a significant magnetocaloric effect due to the high isotropy Gd nuclearity and weak ferromagnetic interactions.

ObjectiveTo elucidate the clinical, radiologic characteristics of Leber’s hereditary optic neuropathy (LHON) associated with the other diseases.Materials and methodsClinical data were retrospectively collected from hospitalized patients with LHON associated with the other diseases at the Neuro-Ophthalmology Department at the Chinese People’s Liberation Army General Hospital (PLAGH) from December 2014 to October 2018.ResultsA total of 13 patients, 24 eyes (10 men and 3 women; mean age, 30.69 ± 12.76 years) with LHON mitochondrial DNA (mtDNA) mutations, were included in the cohort. 14502(5)11778(4)11778 &11696(1)12811(1)11696(1)3460(1). One patient was positive for aquaporin-4 antibody (AQP4-Ab), and two were positive for myelin oligodendrocyte glycoprotein antibody (MOG-Ab). Three patients were associated with idiopathic optic neuritis (ON). Two patients were with compression optic neuropathy. Three patients were with the central nervous system (CNS) diseases. One patient was with proliferative diabetic retinopathy (PDR) and one with idiopathic orbital inflammatory syndrome (IOIS). At the onset, visual acuity (VA) in eighteen eyes was below 0.1, one eye was 0.5, five eyes were above 0.5, while VA in sixteen eyes was below a 0.1 outcome, three eyes experienced moderate vision loss. MRI images showed T2 lesions and enhancement in nine patients who received corticosteroids treatment; additional immune modulators treatment was performed on two patients. None of the patients had relapse during the follow-up time.ConclusionLeber’s hereditary optic neuropathy can be accompanied with multiple-related diseases, especially different subtypes of ON, which were also exhibited with IOIS and compression optic neuropathy for the first time in this cohort. This condition may be a distinct entity with an unusual clinical and therapeutic profile.

PurposeFor patients with symptomatic middle cerebral artery (MCA) atherosclerotic stenosis, identifying the potential stroke mechanisms may contribute to secondary prevention. The purpose of the study is to explore the relationship between stroke mechanisms and the characteristics of culprit plaques in patients with atherosclerotic ischemic stroke in the M1 segment of the middle cerebral artery (MCA) based on high-resolution vessel wall imaging (HR-VWI).MethodsWe recruited 61 patients with acute ischemic stroke due to MCA atherosclerotic stenosis from Shenzhen Bao'an District People's Hospital. According to prespecified criteria based on infarct topography and magnetic resonance angiography, possible stroke mechanisms were divided into parent artery atherosclerosis occluding penetrating artery (P), artery-to-artery embolism (A), hypoperfusion (H), and mixed mechanisms (M). The correlation between the characteristics of MCA M1 culprit plaque and different stroke mechanisms was analyzed using HR-VWI. The indicators included plaque surface irregularity, T1 hyperintensity, location, plaque burden (PB), remodeling index (RI), enhancement rate, and stenosis rate.ResultsParental artery atherosclerosis occluding penetrating artery was the most common mechanism (37.7%). The proposed criteria showed substantial to excellent interrater reproducibility (κ, 0.728; 0.593–0.863). Compared with the P group, the surface irregularity, T1 hyperintensity, and obvious enhancement of the culprit plaque in the A group were more common (p < 0.0125). Compared with the other stroke mechanisms, positive remodeling of culprit plaques was more common (p < 0.0125), the RI was greater (p < 0.05), and the PB was the smallest (p < 0.05) in the P group. The enhancement ratio (ER) was smaller in the P group (p < 0.05). Compared with the A group, T1 hyperintensity of the culprit plaque was more common in the H group (p < 0.0125), and the stenosis rate was greater (p < 0.05). After adjustment for clinical demographic factors in the binary logistic regression analysis, the enhancement level (odds ratio [OR] 0.213, 95% CI (0.05–0.91), p = 0.037) and PB of culprit plaque (OR 0, 95% CI (0–0.477), p = 0.034) were negatively associated with P groups.ConclusionThe culprit plaque characteristics of patients with symptomatic MCA atherosclerotic in different stroke mechanisms may be evaluated using HR-VWI. The plaque characteristics of different stroke mechanisms may have clinical value for the selection of treatment strategies and prevention of stroke recurrence.Clinical trial registrationIdentifier: ChiCTR1900028533.

Privacy protection has received a lot of attention in recent years since in the era of big data, abundant information about individuals can be easily acquired. Meanwhile, as a prerequisite for effective privacy protection, the measurement of privacy disclosure is essential. Although some work has been done on the evaluation of privacy disclosure via quantification for the protection of privacy, not much attention has been placed on exploring the relationships between privacy information, resulting in underestimation, if not ill-formed reasoning, of privacy disclosure. In this paper, we propose an ontology-based approach to measure privacy disclosure by exploring the relationships between privacy information based on the WordNet. We first propose an algorithm for deriving or measuring privacy disclosure based on a set of words or concepts from text data related to individuals to ensure that the disclosure of certain user privacy can still be deduced and measured even if the set of words or concepts don’t seem to be much related to it. We then perform a set of experiment by applying the proposed algorithm to some public information of ten public figures from different walks of life to evaluate the effectiveness of the algorithm and to shed some light on the characteristics of privacy disclosure in the real world in the era of big data. The work can thus serve as the foundation for the development of mechanisms for limiting or reducing privacy disclosure to achieve better protection of individual privacy.

OBJECTIVE To investigate the molecular mechanisms underlying the effects of arsenic trioxide (As2O3) in combination with leflunomide on the hamster-to-rat heart xenotransplant. METHODS Transplantation of LVG hamster hearts to Lewis rats was performed by anastomosis of vessels in the neck using end-to-end anastomosis with a non-suture cuff technique. Four groups of recipient rats (n=6 in each) were treated with normal saline (control), As2O3 [5 mg/(kg·day) intraperitoneally], leflunomide [5 mg/(kg·d) orally], or leflunomide [5 mg/(kg·d)+As2O3 [5 mg/(kg·d)] in combination. Donor hearts and/or rat spleens were harvested and analyzed 4 days after transplantation. Quantitative reverse-transcription polymerase chain reaction and Western blot analysis were performed to detect the expression of the nuclear factor erythroid-derived factor 2-related factor (Nrf2) and its target gene heme oxygenase-1 (HO-1), Treg cell marker fork-head Box P3 (FOXP3), apoptosis-associated proteins Bcl-2, Bax, and cleaved caspase-3. Immunohistochemical staining was used to detect the levels of inflammatory natural killer cell and macrophage infiltration, intercellular cell adhesion molecule-1 (ICAM-1) and complement C3. RESULTS Expression of Nrf2-ARE-HO-1 signaling pathway was upregulated in heart xenografts in rats treated with As2O3 plus leflunomide compared with control rats or rats treated with either drug alone (P

Renal cell carcinoma (RCC) is a kidney cancer that is originated from the lined proximal convoluted tubule, and its major histological subtype is clear cell RCC (ccRCC). This study aimed to retrospectively analyze single-cell RNA sequencing (scRNA-seq) data from the Gene Expression Omnibus (GEO) database, to explore the correlation among the evolution of tumor microenvironment (TME), clinical outcomes, and potential immunotherapeutic responses in combination with bulk RNA-seq data from The Cancer Genome Atlas (TCGA) database, and to construct a differentiation-related genes (DRG)-based prognostic risk signature (PRS) and a nomogram to predict the prognosis of ccRCC patients. First, scRNA-seq data of ccRCC samples were systematically analyzed, and three subsets with distinct differentiation trajectories were identified. Then, ccRCC samples from TCGA database were divided into four DRG-based molecular subtypes, and it was revealed that the molecular subtypes were significantly correlated with prognosis, clinicopathological features, TME, and the expression levels of immune checkpoint genes (ICGs). A DRG-based PRS was constructed, and it was an independent prognostic factor, which could well predict the prognosis of ccRCC patients. Finally, we constructed a prognostic nomogram based on the PRS and clinicopathological characteristics, which exhibited a high accuracy and a robust predictive performance. This study highlighted the significance of trajectory differentiation of ccRCC cells and TME evolution in predicting clinical outcomes and potential immunotherapeutic responses of ccRCC patients, and the nomogram provided an intuitive and accurate method for predicting the prognosis of such patients.

Fresh mulberry leaf vegetable is nutritive and becoming popular. However, available preservation technologies are deficient. In present work, the effects of two kinds of modified atmosphere packaging on postharvest quality of fresh mulberry leaf vegetable stored at 4 °C were evaluated. The respiration rate of samples in the modified polyethylene packages (MP20) was 12.88–22.65% lower than that in normal polyethylene packaging (CK). The content of total soluble solids, soluble protein, and total polyphenol in MP20 was less changed than that in CK, and the vitamin C retention was higher as well. Moreover, the lignin content in MP20 was lower than that in CK during storage (19.79% vs 13.38% at day 8), and that was significantly positively related to the polyphenol oxidase and peroxidase activities inhibition. Taken together, a packaging with moderate gas permeability (MP20) is suitable for nutrition maintenance and lignification inhibition of fresh mulberry leaf vegetable during cold storage.

Additional file 1: Figure S1. Chemicalstructure of N6. Figure S2. Chemicalstructure of N6-COOH-miniPEG. Figure S3. Chemical structure of N6-NH2-miniPEG.Figure S4. Chemical structure of N6-NH2-PEG6. Figure S5. Chemicalstructure of N6-NH2-PEG12. Figure S6. Chemical structure of N6-NH2-PEG24. Figure S7. Chemicalstructure of N6-Cys7-miniPEG. Figure S8. Chemicalstructure of N6-Cys16-miniPEG. Figure S9. CD of N6 and N6-COOH-miniPEG indifferent solutions. Figure S10. Interaction of N6 and N6-COOH-miniPEG with cell membrane. Outer membrane permeabilization of E. coli CVCC195(A) and S. pullorum CVCC533 (B) cells after treated with N6and N6-COOH-miniPEG. Figure S11. Interactionof N6 and N6-COOH-miniPEGwith cell membrane. Inner membranepermeabilization of E. coli CVCC195 (A) and S. pullorum CVCC533 (B) cells. Bacterial cells were treated with 1×, 2× or 4× MIC for 5, 30 or 120 minand analyzed by flow cytometry. Figure S12. Interactionof N6 and N6-COOH-miniPEGwith cell membrane. (A-D) Effects of N6 and N6-COOH-miniPEG on E. coli CVCC195 (A,B) and S. pullorum CVCC533 (C, D) cytoplasmicmembrane potential. Figure S13. Binding affinity of N6 andN6-COOH-miniPEG to LPS. Figure S14. TEM images of E. coli CVCC195 and S. pullorumCVCC533 cells treated with N6 and N6-COOH-miniPEG. After treatment with 4 × MIC N6 or N6-COOH-miniPEGfor 2 h, E. coli CVCC195 and S. pullorum CVCC533 cells weredehydrated, sputtered, and observed on JEM1400 (JEDL, Tokyo, Japan). Figure S15. Effects of N6 and its N6-COOH-miniPEG on organ injury in mice.The mice were infectedintraperitoneally with E. coli CVCC195 (1×109 CFU/mL, 200 μL)and treated with N6 (4 μmol/kg) or N6-COOH-PEG (4 μmol/kg). The livers,spleens, kidneys and lungs were harvested from the mice sacrificed at 5 d afterinfection. Figure S16. Effectsof N6 and its N6-COOH-miniPEG on organ injury in mice. The mice wereinfected intraperitoneally with S. pullorum CVCC533 (5 × 107CFU/mL, 200 μL) and treated with N6 (10 μmol/kg) or N6-COOH-PEG (10 μmol/kg).The livers, spleens, kidneys and lungs were harvested from the mice sacrificedat 48 h after infection. Figure S17. Effects ofN6 and N6-COOH-miniPEGon organ injury in mice.Mice were infectedintraperitoneally with S. pullorum CVCC533 (5 × 107 CFU/mL,200 μL) and treated with N6 (10 μmol/kg) or N6-COOH-miniPEG (10 μmol/kg). Livers, spleens, kidneys and lungs were harvested from mice sacrificed at 4 dafter infection. CK group: The livers, spleens, kidneys, and lungs were normal; Infected S. pullorum CVCC533 group: Thereis “bridgingnecrosis” around the confluent area of the liver, a marked decrease in the density oflymphocytes in the splenic nodes, diffuse inflammatory cell infiltration in therenal interstitium, “honeycomb” changes throughout the lung tissue, and a large amount of bloody exudate in thealveolar cavity (arrow) (× 200,scale bar = 100 μm); N6 treatment group: Foci of hepatocyte necrosis are seenin the lobules of the liver, localised reduced lymphocyte density in thesplenic nodules, localised renal tubular degeneration and atrophy, and a smallamount of inflammatory cell infiltration in the interstitial lung (arrow) (× 200, scale bar = 100 μm); N6-COOH-miniPEG treatment group: Focal foci of hepatocyte necrosis are seen inthe lobules of the liver, localised reduced lymphocyte density in the splenicnodules, localised renal tubular degeneration and atrophy, and a small amountof scattered inflammatory cell infiltration in the interstitial lung (× 200, scale bar = 100 μm); CIP treatment group: Localized inflammatory cell infiltration in the hepaticsinusoids, reduced lymphocyte density in the splenic nodules, localizedscattered inflammatory cell infiltration in the renal interstitium, markedwidening of the alveolar septa and narrowing of the alveolar cavity (× 200, scale bar = 100 μm). Table S1. Proportion of secondary structure of N6 and N6-COOH-miniPEG in different solutions. Table S2. MIC values (μg/mL) of N6 and N6-COOH-miniPEG against E. coli CVCC195 in differentconditions.

The extensive use of large-area high temperature superconducting (HTS) thin films has emerged in superconducting microwave devices. The interest in Tl-based HTS films arises from their high critical temperature (Tc), allowing the microwave device made on Tl films to work above the liquid nitrogen temperature zone. Here, we introduce a simplified two-step method to fabricate high-quality Tl2Ba2CaCu2O8 (Tl-2212) films on 2-inch LaAlO3 substrates. This method enables the preparation of Tl-2212 films to be easy and repeatable, promoting the theoretical research and practical applications of Tl-based films. Based on the high reproducibility of this fabricating process, we studied the superconducting properties of Tc, the critical current density Jc (77 K, zero field) and surface resistance (Rs) of 2-inch Tl-2212 films. Results show that the Tc values of the sample films prepared at different conditions vary from 99 K to 103 K, depending on the oxygen content; the Jc of the films ranges from 0.7 to 1.8 MA/cm2, relying on the surface roughness. On the basis of the two-fluid model, the influence of Jc on Rs of the Tl-2212 films is incorporated to explain the variation of Rs in different samples.

Ceramic membrane condensers that are used for water and waste heat recovery from flue gas have the dual effects of saving water resources and improving energy efficiency. However, most ceramic membrane condensers use water as the cooling medium, which can obtain a higher water recovery flux, but the waste heat temperature is lower, which is difficult to use. This paper proposes to use the secondary boiler air as the cooling medium, build a ceramic membrane condenser with negative pressure air to recover water and waste heat from the flue gas, and analyze the transfer characteristics of flue gas water and waste heat in the membrane condenser. Based on the experimental results, it is technically feasible for the ceramic membrane condenser to use negative pressure air as the cooling medium. The flue gas temperature has the most obvious influence on the water and heat transfer characteristics. The waste heat recovery is dominated by latent heat of water vapor, accounting for 80% or above. The negative pressure air outlet temperature of the ceramic membrane condenser can reach 50.5 °C, and it is in a supersaturated state. The research content of this article provides a new idea for the water and waste heat recovery from flue gas.

To achieve the deep recovery of exhaust waste heat, a combined cooling heating and power (CCHP) dynamic exhaust low temperature waste heat coupled air source heat pump system is proposed in this paper. Aspen Plus software was used to simulate the system and analyze the effects of the recyclable waste heat of the system, the coefficient of performance (COP) of the heat pump and the impact of the primary energy utilization rate. The results showed that under the design condition, the exhaust waste heat of CCHP system was 1.22 kW, the recyclable waste heat of heat pump system was up to 1.07 kW, the exhaust waste heat recovery rate was 87.7%. The COP was up to 4.66, increased 39.5%. The primary energy utilization efficiency was increased by 3.9%. It solves the problem of heat pump evaporator frosting and poor performance of low temperature in cold regions. This study provides an important reference for the combined and efficient application of CCHP systems and heat pump units.

Supplemental material, TanS_PE_ON_paper_supp for Vision improvement in severe acute isolated optic neuritis after plasma exchange treatment in Chinese population: a prospective case series study by Shaoying Tan, Tsz Kin Ng, Quangang Xu, Mo Yang, Yuan Zhuang, Jie Zhao, Huanfen Zhou, Da Teng and Shihui Wei in Therapeutic Advances in Neurological Disorders

To overcame the shortcoming that the CBTC interoperable system cannot deal with temporary speed limit informaiton across ZC control zone, a new interoperable DSU structure incorporated into the existing CBTC is studied and designed. Interface between subsystems and Data Storage Unit (DSU) systems changes are illustrated and analyzed, and also the interactions between subsystems are given. Based on characteristics of interoperation CBTC system, a novel DSU system architecture is designed, its modules are divided into the temporary speed restriction module, line database module and system maintenance module. Performance test of DSU system is conducted in the interoperation test platform in Chongqing. The results show that DSU system can meet the requirement that trains can cross the line and improve the efficiency of interoperable operation.

Ultrasensitive polydopamine bi-functionalized surface enhanced Raman scattering immunoassay expedites exosome-based diagnosis and classification of pancreatic cancer., Early diagnosis and metastasis monitoring for pancreatic cancer are extremely difficult due to a lack of sensitive liquid biopsy methods and reliable biomarkers. Herein, we developed easy-to-prepare and effective polydopamine-modified immunocapture substrates and an ultrathin polydopamine-encapsulated antibody-reporter-Ag(shell)–Au(core) multilayer (PEARL) Surface-Enhanced Raman Scattering (SERS) nano-tag with a quantitative signal of the Raman reporter at 1072 cm–1, which achieved ultrasensitive and specific detection of pancreatic cancer-derived exosomes with a detection limit of only one exosome in 2 μL of sample solution (approximately 9 × 10–19 mol L–1). Furthermore, by analyzing a 2 μL clinical serum sample, the migration inhibitory factor (MIF) antibody-based SERS immunoassay could not only discriminate pancreatic cancer patients (n = 71) from healthy individuals (n = 32), but also distinguish metastasized tumors from metastasis-free tumors, and Tumor Node Metastasis (TNM) P1–2 stages from the P3 stage (the discriminatory sensitivity was 95.7%). Thus, this novel immunoassay provides a powerful tool for the early diagnosis, classification and metastasis monitoring of pancreatic cancer patients.

Privacy protection is a fundamental issue in the era of big data. For personalized privacy protection, it is necessary to measure the amount or the degree of privacy leakage. To facilitate such measurement, semantic similarities and relationships of words should be determined since the words may come from multiple sources and present themselves in as many different ways as one can imagine, an intrinsic nature of big data. WordNet has been widely used for measuring the semantic similarity of words. This paper aims at analyzing the suitability of applying WordNet to measuring the semantic similarity or relatedness of words in the field of privacy. The analysis includes an experiment designed to obtain human rating scores as the benchmark dataset and a comprehensive comparison between results from four WordNet based measures and the human rating scores. The conclusion of the analysis is that current WordNet based measures are not very suitable for privacy measurement. Therefore, this paper also provides some suggestions on possible ways of enhancing WordNet to improve the effectiveness of semantic similarity or relatedness measurement in the field of privacy to support more effective and personalized privacy protection.

The toxicity and bioavailability of single arsenic species have been widely investigated, however, the biological effects of mixed arsenic species co-existing in natural waters still remain unknown. The objective of this work was to discern the adverse effects of combined arsenite (As(III)) and dimethylarsenic acid (DMA) on diatom Nitzschia palea. The combined ecotoxicity of As(III) and DMA on N. palea was observed to be time-dependent and showed dose-effect relation. The toxicity of DMA and As(III) mixture was higher than individual DMA or As(III) when the As(III) concentration was in the range of 0.085–0.316 mg L−1. As the As(III) concentration increased from 0.487 to 0.858 mg L−1, the antagonistic effect was found, which could be due to the higher thiols contents in the thiol-containing proteins (e.g., frustulins, silaffins and other glycoproteins). The content of malondialdehyde (MDA) in the treatment of mixed arsenic species was found to be at the same level compared to the As-free control after 72 h of exposure, indicating that the co-toxicity of As(III) and DMA on diatom frustules was not significant. Furthermore, the increase of frustule formation rate in the mixture of EC50 As(III)-EC10 DMA at 72 h exposure time indicated that the damaged diatom cell walls was likely repaired gradually. The results from this study suggested that the effects of co-existed arsenic species were concentration-specific and should be considered in the risk assessment of arsenic and development of water quality criteria for the protection of aquatic ecosystems.

The continuous discharge of pharmaceutical and personal care products (PPCPs) into aquatic environment and their potential threaten to ecological environment or human health has received more and more attention all over the world. Algae are primary producers in aquatic environment and play an important role in ecosystem balance and stabilization. In this review, the concentrations of PPCPs in natural waters from different countries and regions are introduced to demonstrate their characteristics of pollution in aquatic environment. Furthermore, we reviewed some progresses on the toxicity, bioaccumulation and ecological risk of PPCPs. We introduced the toxicity effect and mechanism of PPCPs to algae, the bioaccumulation of PPCPs in algae, as well as the ecological risks of PPCPs in surface water. The review will provide references for development of PPCPs related criteria and assessment of ecological risks in aquatic environment.药物和个人护理品(PPCPs)因持续排放到水环境且对水生态环境和人类健康造成潜在威胁而受到广泛关注.藻类作为水体重要的初级生产者,对水体的生态平衡和稳定起着重要的作用.本文围绕地表水PPCPs污染,介绍了不同国家和地区地表水体中PPCPs的浓度分布和污染特征,并从毒性效应、生物累积及潜在的生态风险等方面,综述了PPCPs对藻类的污染生态学研究进展,阐述PPCPs对藻类的毒性效应及机制,PPCPs在藻类中的生物累积,以及地表水体PPCPs的生态风险,为地表水体PPCPs的相关标准制定和修订,以及水体生态环境健康风险评价提供参考.

In order to study the influence of seismic excitation on the rocket body during the propellant injection and launch waiting state of a certain rocket, the dynamic response analysis of the rocket structure was carried out, and the seismic response spectrum analysis and time-history analysis were respectively used to solve the structural dynamic response.SolidWorks was used to establish a simplified three-dimensional model of the rocket body, and ANSYS Workbench was imported to solve the static stress, modal frequency and mode of the rocket. Time-history analysis of El-centro seismic wave data was carried out, and Fourier transform was applied to frequency domain spectrum for seismic response spectrum analysis. Cloud maps of structural equivalent stress, displacement and strain were obtained. After numerical verification, the results show that the rocket meets the safety requirements of seismic resistance, and more research methods are verified for the optimization of the rocket body.

Electromagnetic ejection technology is a new launching technology which uses electromagnetic force to accelerate the projectile to ultra-high sound speed. This technology can break through the speed limit of traditional gunpowder launching, and realize the accurate control of exit speed by controlling the excitation pulse current. Four track electromagnetic launcher is a special enhanced electromagnetic launcher, which has many advantages that dual track electromagnetic launcher does not have. Its development greatly promotes the application of electromagnetic launch technology in aerospace field. In this paper, according to the practical needs of electromagnetic space launch technology, a simple four orbit electromagnetic launch device is designed and established; the finite element analysis of the model is carried out, and the electromagnetic and current characteristics are simulated, and the skin effect and proximity effect of current are obviously observed; the theoretical analysis and formula derivation of inductance gradient are carried out, and finally two kinds of inductance gradient are proposed based on the finite element theory simulation A simple example is given.

Figure 2 in the original paper (Chin. Phys. B 27 057403 (2018)]) is replaced by a new one.

Cutting force, cutting heat and tool wear are closely related to the friction characteristics of tool-chip interface in the process of metal cutting. The variation of the cutting speed and temperature have been analyzed by the distribution of stress and strain in the primary and the secondary shear zone. A new friction model has been established to analyze the contact length between cutting tool and chip and local friction coefficient at the sliding zone. Cutting experiments have been performed in the process of carbide tools cutting the titaniumTi6Al4V, the contact length of sticking zone and sliding zone and friction coefficient have been analyzed by measured cutting force. The simulation of cutting process has been carried out based on Deform software, then the simulation results have been compared with the test ones, which verifies the accuracy of the established model.

The high temperature oxidation phenomenon will occur on the tool-workpiece contact area when machining the superalloy. Two kinds of cemented carbide tools (YG6X, YG8) are selected, the coated carbide tool and coated ceramic tool which are suitable for machining superalloy are selected. The resistance furnace is used for heating tool material, and the oxidation resistance experiments are carried out. The results show that: WC which is included in the cemented carbide tool is oxidized to WO3 and the Co is oxidized to Co3O4, Ti which is included in the coated carbide tool is oxidized to TiO2. The grain of the tool is smaller, the oxidation resistance is better. The oxidation resistant of coated carbide tool is better than the non-coated tools. The coated ceramic tool is not substantially oxidized in high temperature situation. The merits order of the oxidation resistant properties is that: coated ceramic tool>coated carbide tool > YG6X>YG8.

Filtration membranes (FMs), with robust anti-fouling performance, are highly desirable for practical oily wastewater purification but still a challenge to be realized without water pre-wetting procedure. Herein, we demonstrate a novel and effective route to address this challenge by decorating MnO2-x nanowires on carbon cloth membrane (MCM) via simple hydrothermal method, in which the existence of oxygen vacancies on the outer surface of MnO2-x nanowires can greatly enhance the H2O adsorption capacity even under oil, thus the oil-fouling problem can be solved by simply immersing the oil-polluted membrane into water and shaking. Besides the superamphiphilic performance in air and underwater superoleophobic (underwater oil contact angle > 155° against diverse oils), our MCM also exhibits unexpected under-oil superhydrophilic properties, Moreover, high separation efficiency for diverse oil/water mixtures (>99.8%) and oil-in-water emulsions (>98.3%) have been also achieved based on our product. These outstanding properties make our sample hold a great potential in practical oily/water purification.

The total focusing method (TFM) attracts much interest because of high image resolution and large dynamic range. However, the signal-to-noise ratio (SNR) of TFM is relatively low due to single-element emission. Especially in highly attenuating materials, the signal amplitude may be reduced with depth to a level lower than the electronic noise introduced by the signal acquisition system. Golay-coded excitation was introduced to overcome this problem, however, the double-excitations reduce the time resolution and may lead to negative decoding performance due to the relative change of scanning positions. In this work, the AB code conversion factor was used to realize the TFM imaging based on Golay-coded single-excitation which has a good performance as traditional Golay-coded excitation. A series of simulations and experiments were conducted to compare performance of TFM using un-coded excitation, Golay-coded excitation and modified Golay-coded excitation. TFM using modified Golay-coded excitation could overcome the disadvantages of double-excitation, and has approximately the same SNR gain as TFM using traditional one.

As the strong engineering application background of professional course knowledge in the teaching process of measurement and control and photoelectric majors, it is meaningful to guide and improve the ability of understanding the relationship of theory and instances by using the real engineering application instances. Based on concrete structure system and self-operation measurement of the instances, its comprehensive principle and structure characteristics will be analyzed with the studied knowledge, then students can draw up technical parameters, and design the desired specific mechanical structure, circuit and the measurement and control software. Through the practical teaching exploration, the teaching model of engineering application not only can guide the students to think and solve problems in a practical way, but also can further stimulate students’ own imagination and creativity, which could deepen the students understanding and mastering the knowledge of professional courses and engineering application and build a good foundation for future work and further study. 工

The registration of point cloud is important for large object measurement. A measurement method for coordinate system transformation based on robot is proposed in this paper. Firstly, for obtaining extrinsic parameters, the robot moves to three different positions to capture the images of three targets. Then the transformation matrix X between camera and tool center point (TCP) coordinate systems can be calculated by using the known parameters of robot and the extrinsic parameters, and finally the multi-view coordinate system can be transformed into robot coordinate system by the transformation matrix X. With the help of robot, the multi-view point cloud can be easily transformed into a unified coordinate system. By using robot, the measurement doesn’t need any mark. Experimental results show that the method is effective.

A hospital-based cross-sectional study was performed, including 117 psoriatic patients and 117 controls matched for age, gender, and body mass index. Psoriatic patients had higher levels of serum uric acid (6.25 ± 1.62 vs 5.71 ± 1.35 mg/dl; P=0.019) and significantly greater prevalence of hyperuricemia (31.6% vs 16.2%; P=0.009) than individuals without psoriasis. Psoriatic patients had significantly higher serum uric acid than controls in subjects without metabolic syndrome. Multivariate logistic regression analysis showed that psoriasis can be a strong predictor of hyperuricemia (odds ratio 2.61; 95% confidence interval 1.34-5.00; P=0.004).

As the application of meta-cognition theory in learning filed, the structure of meta-learning ability has not unified definition. This paper tried to define it from the perspective of empirical analysis. Three dimensions and six ability factors constituted the structure of meta-learning ability, basing on which meta-learning ability structure questionnaire was prepared. After sampling survey, through item analysis, exploratory factor analysis, reliability analysis and validity analysis, the structure of meta-learning ability was verified, which can measure undergraduates’ meta-learning ability comprehensively.

Additional file 1. Additional tables and figures.

The avionics system is a core component of the civil aircraft. To reduce the risk and cost of developing avionics system, shorten the development cycle, through the development process of avionics systems, variety of simulation and verification must be done. The bus excitation signals need to be provided for each avionics unit and the signals from each avionics unit need to be received and processed. The multilayer abstract model and organizational structure model of the bus excitation system was established. And a complete bus excitation system was designed. In this system, the ARINC429 bus signals and discrete signals for communication and navigation equipments were provided, and the signals from the equipments were received and processed. This system has been tested, and one practical application example of the system was given.

In this paper a 6-DOF(Degree of Freedom) vibration isolation platform with structural configuration of 3CPS (3 Cylindrical-Prismatic-Spherical)-1UPS (1 Universal-Prismatic-Spherical) parallel mechanism is proposed. Firstly, the dynamic model is developed through virtual work principle. The transfer function and the complex frequency response function were obtained from the dynamical equation. Then, 36 amplitude frequency diagrams are obtained from the frequency response function. By analyzing the 36 amplitude frequency diagrams, 10 vibration coupling terms were chosen. The range of the spring stiffness coefficient and the range of the damping coefficient of the magneto-rheological damper are determined by analyzing the acceleration transmissibility of the 10 vibration coupling terms. At last, an integrated optimization combining structural and controller optimization is developed. The optimal parameters of the parallel mechanism are obtained through Genetic Algorithm (GA). This work is significant for the prototype design and verification of the vibration isolator.

In titanium alloy machining, under different cooling lubrication conditions, the variation of tool wear and chip morphology have a certain effect on the surface roughness. Under different cooling lubrication conditions, in order to analyze the variation of tool wear, chip morphology and surface roughness, the surface roughness values are measured ​​and the variation in tool wear and chip morphology are observed, and then the interaction relationship between the tool wear and the chip morphology is analyzed. The results show that the tool wear and chip morphology influence on the surface roughness. Under different cooling lubrication, the rake face wear do not change significantly, but wet cooling and MQL play a protective role for the flank face wear.