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Background Study: As flipped learning is a flexible pedagogical methodology to tailor students' needs and maximize the learning effects, this study integrated peer learning with MosoTeach-supported flipped mode in an undergraduate blended EFL course. MosoTeach is a popular online learning platform in China with a variety of learning resources. Objectives: The study aimed to test the impact of MosoTeach flipped learning (MTFL) mode on undergraduate EFL students' perceived motivation, participation, feedback, and test performance. Methods: A quasi-experimental design was carried out in Z university during the spring semester of 2020, with the experimental group (n = 34) adopting the MTFL model and a control group (n = 33) the non-flipped mode. Results and Conclusions: The independent t-test results showed that the experimental MTFL group outperformed the control group in post-test scores, and a positive correlation was found in the relationship between the experimental MTFL group's post-test scores and MosoTeach learning experience points (LEPs). Moreover, the course perception questionnaire survey indicated a higher level of students' perceived motivation, participation, and feedback in the experimental MTFL group, which corresponded to the results of the content analysis of students' responses to open-ended questions and reflective reports. But students in both groups experienced challenges such as isolation, procrastination and technological anxiety.

Acoustic levitation is widely used in non-container measurement and non-contact manipulation. Particles in the single-axis acoustic levitation are easily unstable in the radial direction under external perturbations. In order to explore the instability in the acoustic levitation during radial perturbations, a nonlinear acoustic levitation model considering the coupling of radial and axial vibration is proposed to analyze the dominant factors influencing the levitation stability, an acoustic levitation system consisting of a transducer and a plane reflector is established, and high-speed photography is used to observe the vibration behavior of the particle with large radial vibration and the levitation stability. The simulation results are compared and verified with the experiments, which indicate that the reduction in axial trapping stiffness due to radial vibration plays a vital role in the levitation instability. The present model can characterize the radial anti-interference ability of different levitators as well as predict the movement trajectories of levitated particles after being disturbed, which is helpful to optimize the design of acoustic levitators and provide guidance for acoustic manipulation. [ABSTRACT FROM AUTHOR]

Writing is a recording process involving complex dynamic behaviours, which is closely connected with authentic contexts. A free authentic context can form a link with students' life experience and their prior knowledge, so that students' deep writing skills can be stimulated. However, in traditional writing activities, the lack of authentic experience is an important reason for students' poor writing achievements and low behavioural engagement. To address this problem, the current study used a spherical video-based virtual reality (SVVR)-supported Chinese composition writing approach, which can provide authentic contexts to support students' deep writing. An SVVR experiential learning model was developed and a quasi-experiment was conducted in a primary school to verify the effectiveness of the proposed approach. A total of 59 fourth-grade students from China were recruited and were randomly divided into the experimental group, which adopted the SVVR-supported learning approach, and the control group, which adopted the non-SVVR-supported learning approach. The results show that the proposed approach can promote students' transition of learning behavioural engagement from medium to high, as well as the development of deep writing skills. It was found that students learning with the SVVR approach who acquired better deep writing skills tended to demonstrate better writing performance in relation to linguistic expressiveness and creative thinking than the students learning with the non-SVVR approach.

The oriented single-crystalline Zirconium Carbide (ZrC) nanowires were controllably synthesized on a graphite substrate by chemical vapor deposition (CVD) with optimized growth parameters involving Zirconium tetrachloride (ZrCl4), flow of methane (CH4), and growth temperature. The length of nanowires is above 10 µm while the diameter is smaller than 100 nm. A single ZrC nanowire was picked up and fixed on a tungsten tip for field emission measurement. After surface pretreatments, a sharpened and cleaned ZrC nanowire emitter showed a high emission current density of 1.1 × 1010 A m−2 at a low turn-on voltage of 440 V. The field emission is stable for 150 min with a fluctuation of 1.77%. This work provides an effective method for synthesizing and stabilizing single-crystalline ZrC nanowire emitters as an electron source for electron-beam applications.

Objective To analyze the current situation of direct exemption of clinical blood fess for voluntary blood donors and their family members in Henan Province, in order to improve and fully implement the policy. Methods According to the policy on blood fees exemption issued by China and Henan Province in 2019,the data of hospitals in 18 prefecture-level cities in Henan from 2020 to 2021 were continuously collected from the system of clinical blood fees exemption,including the way of exemption,the number of people (times) of exemption,exemption amount, the proportion of blood fees exemption and the total exemption rate. The experience gained in the past two years after the implementation of the policy was summarized,and the existing problems and causes were analyzed. Results The rates of direct exemption of blood fees in Henan Province in 2020 and 2021 were 34.53% (8 709/25 221) and 71.68%(23 587/32 906) (P

Using silicon/reduced graphene oxide (Si/rGO) composites as lithium-ion battery (LIB) anodes can effectively buffer the volumetric expansion and shrinkage of Si. Herein, we designed and prepared Si/rGO-b with a sandwiched structure, formed by a duple combination of ammonia-modified silicon (m-Si) nanoparticles (NP) with graphene oxide (GO). In the first composite process of m-Si and GO, a core–shell structure of primal Si/rGO-b (p-Si/rGO-b) was formed. The amino groups on the m-Si surface can not only hybridize with the GO surface to fix the Si particles, but also form covalent chemical bonds with the remaining carboxyl groups of rGO to enhance the stability of the composite. During the electrochemical reaction, the oxygen on the m-Si surface reacts with lithium ions (Li+) to form Li2O, which is a component of the solid–electrolyte interphase (SEI) and is beneficial to buffering the volume expansion of Si. Then, the p-Si/rGO-b recombines with GO again to finally form a sandwiched structure of Si/rGO-b. Covalent chemical bonds are formed between the rGO layers to tightly fix the p-Si/rGO-b, and the conductive network formed by the reintroduced rGO improves the conductivity of the Si/rGO-b composite. When used as an electrode, the Si/rGO-b composite exhibits excellent cycling performance (operated stably for more than 800 cycles at a high-capacity retention rate of 82.4%) and a superior rate capability (300 mA h/g at 5 A/g). After cycling, tiny cracks formed in some areas of the electrode surface, with an expansion rate of only 27.4%. The duple combination of rGO and the unique sandwiched structure presented here demonstrate great effectiveness in improving the electrochemical performance of alloy-type anodes.

Background: Transseptal puncture (TSP) performed with the Brockenbrough (BRK) needle is technically demanding and carries potential risks. The back end of the percutaneous transluminal coronary angioplasty (PTCA) guidewire is blunt and flexible, with good support, it can puncture the right ventricle-free wall, which is thicker than the atrial-septum. The guidewire is thin and easy to manipulate. This study evaluated the performance of TSP with a PTCA guidewire and microcatheter without a needle. Methods: The back end of a PTCA guidewire was advanced into the Tiger (TIG) catheter, within the SL1 sheath, to puncture the fossa ovalis (FO) under fluoroscopy. Subsequently, the microcatheter was inserted into the left atrium (LA) above the guidewire, and the front end of the guidewire was exchanged in the LA. After the puncture site was confirmed by contrast, the TIG catheter and a 0.032 inch wire were advanced into the LA. Finally, the sheath, with the dilator, was advanced over the wire into the LA. The safety margin of this method was tested in a pig model. Results: The puncture was successful in all seven pigs tested with a puncture-to-sheath entry time of

In order to improve the nutritional and functional value of the mixed congee products, and to improve its stability, the experiment was carried out to prepare mixed congee powders through pulverisation treatments including general (3000 r/min, 1600 W) and superfine grinding (−20 ℃, 960 r/min, 1100 W). The effects of superfine grinding on the particle size distribution, color parameters, hydration properties, filling properties, fluidity properties，micro structure，antioxidant activity, the dissolutions of flavonoids and total polyphenols were investigated, which would provide reference for the application and promotion of superfine grinding in mixed congee processing industry. The results showed that superfine grinding had a significant effect on the physicochemical and functional properties of mixed congee powder (P

To investigate the effect of nitrogen on soil nutrients and microbial communities in peanut field with wheat straw returning under wheat peanut rotation mode, four nitrogen levels (N: 0, 45, 90, and 180 kg/hm²) were set to study the soil nutrient content, soil enzyme activity, soil bacterial community structure and diversity during podding stage. The results showed that under the same nitrogen level, straw returning increased soil nutrient content and soil enzyme activity in peanut field at pod setting stage. Compared to the corresponding nitrogen level, the increase of total nitrogen content and total carbon content in soil with straw returning were 12.8%-23.1% and 20.9% -35.4% respectively, and the increase of microbial biomass carbon and nitrogen content were all higher than 48.3%. Wheat straw returning also affected the relative abundance of bacteria in phylum level and the function of bacteria. Under wheat straw returning conditions, the soil microbial carbon and nitrogen content, soil enzyme activity, and peanut yield all showed a trend of first increasing and then decreasing with the increase of nitrogen application rate. Under 45 kg/hm² nitrogen level, the microbial biomass carbon and nitrogen content were highest, the activities of invertase and cellulase were highest, the soil bacterial richness index was high, and the relative abundance of Proteobacteria and Acidobacteria was most affected by wheat straw returning. Addition, there was no significant difference in soil total nitrogen, total carbon content, and peanut yield between 45 and 90 kg/hm2 nitrogen level. Correlation analysis showed that the composition of soil bacterial community of each treatment was affected by the soil total nitrogen, total carbon, ammonium nitrogen, and microbial biomass carbon and nitrogen content. The results indicate that wheat straw returning and nitrogen application not only affect the soil nutrient content and soil enzyme activity, but also affect the composition of soil bacterial community during peanut pod setting stage. Under the condition of wheat straw returning, the nitrogen application of 45 kg/hm² can not only ensure stable peanut yield, but also increase the microbial biomass carbon and nitrogen content in soil during the pod setting stage and improve the soil micro ecological environment. Therefore, the amount of nitrogen fertilizer application can be reduced in the production of peanut with wheat straw returning. [ABSTRACT FROM AUTHOR]

Developing electrode materials with high voltage and high specific capacity has always been an important strategy for increasing the energy density of lithium-ion capacitors (LICs). However, organic-based electrolytes with lithium salts limit their potential for application in LICs to voltages below 3.8 V in terms of polarization reactions. In this work, we introduce Li[N(C2F5SO2)2] (lithium Bis (pentafluoroethanesulfonyl)imide or LiBETI), an electrolyte with high conductivity and superior electrochemical and mechanical stability, to construct a three-electrode LIC system. After graphite anode pre-lithiation, the anode potential was stabilized in the three-electrode LIC system, and a stable solid electrolyte interface (SEI) film formed on the anode surface as expected. Meanwhile, the LIC device using LiBETI as the electrolyte, and a self-synthesized graphene/single-walled carbon nanotube (SWCNT) composite as the cathode, showed a high voltage window, allowing the LIC to achieve an operating voltage of 4.5 V. As a result, the LIC device has a high energy density of up to 182 Wh kg−1 and a 2678 W kg−1 power density at 4.5 V. At a current density of 2 A g−1, the capacity retention rate is 72.7% after 10,000 cycles.

The extracellular vesicles (EVs) in edible food have a typical saucer-like structure and are nanoparticles released by numerous cells. They have different components and interact with other biological samples in diverse ways. Therefore, these nanoparticles could be used to develop bioactives delivery nanoplatforms and anti-inflammatory treatments to meet the stringent demands of current clinical challenges. This review aims to summarize current researches into EVs from edible plants, particularly those that can protect siRNAs or facilitate drug transportation. We will discuss their isolation, characterization and functions, their regulatory effects under various physiological and pathological conditions, and their immune regulation, anti-tumor, regeneration, and anti-inflammatory effects. We also review advances in their potential application as bioactives carriers, and medicinal and edible plants that change their EVs compositions during disease to achieve a therapy propose. It is expected that future research on plant-derived EVs will considerably expand their application.

Lead and its alloys are commonly used as coolant and liquid spallation neutron targets for advanced nuclear reactors and ADS systems. Pb-Mg alloy may be a potential coolant and maintain an acceptable corrosion rate without additional oxygen control in comparison with LBE. A comparative study on corrosion behavior of two F/M steels (SIMP, T91) and two austenitic steels (316L, 15-15Ti) in liquid Pb-Mg and LBE at 550 °C for 1000 h has been studied in this work. In Pb-Mg, F/M steels show slight dissolution corrosion and austenitic steels show severe dissolution corrosion. In LBE, all steels form oxide layers and a three-layer structure is observed in F/M steels.

BackgroundDry transthoracic pericardiocentesis is challenging and carries the risk of right ventricle (RV) or coronary artery injury. The RV can usually control bleeding automatically. For example, most perforations of the RV caused by pacemaker leads are treated without open surgery. Thus, we performed a transvenous puncture of the RV for dry pericardiocentesis with the back end of a 0.014-inch percutaneous transluminal coronary angioplasty (PTCA) guidewire and a 1.8 Fr microcatheter.MethodsThe back end of a 0.014-inch PTCA guidewire within a 1.8 Fr microcatheter was used to transvenously punctured through the middle of the acute margin of the RV into the pericardial space in 12 Yorkshire swine and 5 beagles. PTCA balloons of different diameters were used to dilate the puncture holes for 15 min under anticoagulation in all the animals to assess the ability of the RV to control the bleeding. Then, for 3 days, the puncture hole was dilated by a 6 Fr catheter in 9 swine and 5 dogs.ResultsThe puncture was successful in all the animals. After withdrawal of the 2.5-mm balloon or the 6 Fr catheter, none of the animals exhibited pericardial effusion, as observed by echocardiography. There was no sustained ventricular arrhythmia or other complications. All the animals survived.ConclusionTransvenous puncture of the right ventricle with the back end of a 0.014-inch PTCA guidewire and 1.8 Fr microcatheter may be feasible and have a good safety margin.

Ants (Hymenoptera: Formicidae) represent the most critical arthropod community in desert ecosystems, where interactions among vegetation, soil, and climate dictate ant assemblages. Nonetheless, our understanding of how various factors influence desert ant assemblages across different spatial and temporal scales remains limited. Therefore, this study aims to analyse the temporal and spatial distribution patterns of desert ants and to determine the effects of precipitation and temperature variations on ant assemblages. To achieve this, we continuously monitored the monthly dynamics of ants at 72 uniform 8m8m grid points in the Gobi Desert ecosystem of Northwest China from 2015 to 2020 using pitfall traps. The results indicated that Messor desertus and Cataglyphis aenescens were the dominant ant species, with significant annual and monthly variations in the number of individuals captured from 2015 to 2020. In 2020, monthly captures of M. desertus exhibited a bimodal pattern, peaking in November, whereas those of C. aenescens exhibited a unimodal pattern, peaking in June. Annual data revealed that population size was significantly positively correlated spatially at a distance of 24 m. Semi-variance analysis and Moran's I indicated that structural factors predominantly controlled the ant assemblages at a small scale from 2015 to 2020. Annual catches of desert ants tended to decrease with increasing annual precipitation, while an opposite trend was rising average annual temperatures. In conclusion, variations in annual and monthly precipitation and temperature influenced the temporal response patterns of desert ants, thereby altering their spatial assemblages. [ABSTRACT FROM AUTHOR]

Abstract Background The ketogenic diet (KD) has been recognized as a potentially effective therapy to treat neuropsychiatric diseases, including epilepsy. Previous studies have indicated that KD treatment elevates γ-Amino butyric acid (GABA) levels in both human and murine brains, which presumably contributes to the KD’s anti-seizure effects. However, this has not been systematically investigated at the synaptic level, and the underlying molecular mechanisms remain to be elucidated. Methods Kainic acid (KA)-induced acute and chronic seizure models were utilized to examine the effects of KD treatment on seizure threshold and epileptogenesis. Synaptic activities in the hippocampus were recorded with the technique of electrophysiology. The effects of the KD on Neuregulin 1 (Nrg1) expression were assessed via RNA sequencing, real-time PCR and Western blotting. The obligatory role of Nrg1 in KD’s effects on seizures was evaluated through disruption of Nrg1 signaling in mice by genetically deleting its receptor-ErbB4. Results We found that KD treatment suppressed seizures in both acute and chronic seizure models and enhanced presynaptic GABA release probability in the hippocampus. By screening molecular targets linked to GABAergic activity with transcriptome analysis, we identified that KD treatment dramatically increased the Nrg1 gene expression in the hippocampus. Disruption of Nrg1 signaling by genetically deleting its receptor-ErbB4 abolished KD’s effects on GABAergic activity and seizures. Conclusion Our findings suggest a critical role of Nrg1/ErbB4 signaling in mediating KD’s effects on GABAergic activity and seizures, shedding light on developing new therapeutic interventions to seizure control.

In recent years, mammalian cells have become the primary host cells for the production of recombinant therapeutic proteins (RTPs). Despite that the expression of RTPs in mammalian cells can be improved by directly optimizing or engineering the expression vectors, it is still influenced by the low stability and efficiency of gene integration. Transposons are mobile genetic elements that can be inserted and cleaved within the genome and can change their inserting position. The transposon vector system can be applied to establish a stable pool of cells with high efficiency in RTPs production through facilitating the integration of gene of interest into transcriptionally active sites under screening pressure. Here, the structure and optimization of transposon vector system and its application in expressing RTPs at high level in mammalian cells are reviewed.

The zinc injection process has been widely used in the primary coolant of PWR nuclear power plants. This study explored its effect in the water coolant of fusion reactors. The research uses the International Thermonuclear Experimental Reactor (ITER) water-cooled experimental simulation circuit, with Fe3O4 particles as corrosion products. The deposition thickness of Fe3O4 on the wall of the stainless steel tube at temperatures from 80 °C to 150 °C was measured by a non-destructive online magnetic thickness measurement. The experimental results show that zinc injection has a significant inhibitory effect on the deposition of corrosion products on the tube wall, especially at the elbow. After adjusting the pH to the optimal value of 9, adding zinc can continue to reduce the thickness of the deposition layer. The results of the microscopic analysis indicated that the Zn injection formed a new dense surface oxide film and inhibited the deposition of Fe3O4 particles on the tube wall. The research results indicate that the chemical process of zinc injection water can be applied to the operation of the water-cooled fusion reactor in future.

Sonneratia apetala Francis Buchanan-Hamilton (Sonneratiaceae, Myrtales), is a woody species with high adaptability and seed production capacity. S. apetala is widely cultivated worldwide as the main species for mangrove construction. However, the study of diseases affecting S. apetala is limitted, with only a few fungal pathogens being recorded. Cryphonectriaceae (Diaporthales) species are the main pathogens of plants. They can cause canker diseases to several trees and thereby seriously threaten the health of the hosts. These pathogens include Cryphonectria parasitica (Cryphonectriaceae) causing chestnut blight on Castanea ( Rigling and Prospero 2017 ) and Cytospora chrysosperma (Cytosporaceae) causing polar and willow canker to Populus and Salix ( Wang et al. 2015 ). Therefore, the timely detection of of Cryphonectriaceae canker pathogens on S. apetala is extremely important for protecting the mangrove forests.Two diaporthalean fungi, Celoporthe guangdongensis and Cytospora rhizophorae have been reported for the first time to cause canker on the branches of S. apetala. C. guangdongensis is significantly pathogenic and C. rhizophorae is saprophytic on S. apetala.

Impurities in pharmaceuticals of potentially hazardous materials may cause drug safety problems. Macrolide antibiotic preparations include active pharmaceutical ingredients (APIs) and different types of impurities with similar structures, and the amount of these impurities is usually very low and difficult to be separated for toxicity evaluation. Our previous study indicated that hepatotoxicity induced by macrolides was correlated with c-fos overexpression. Here, we report an assessment of macrolide-related liver toxicity by ADMET prediction, molecular docking, structure–toxicity relationship, and experimental verification via detection of the c-fos gene expression in liver cells. The results showed that a rapid assessment model for the prediction of hepatotoxicity of macrolide antibiotics could be established by calculation of the -CDOCKER interaction energy score with the FosB/JunD bZIP domain and then confirmed by the detection of the c-fos gene expression in L02 cells. Telithromycin, a positive compound of liver toxicity, was used to verify the correctness of the model through comparative analysis of liver toxicity in zebrafish and cytotoxicity in L02 cells exposed to telithromycin and azithromycin. The prediction interval (48.1∼53.1) for quantitative hepatotoxicity in the model was calculated from the docking scores of seven macrolide antibiotics commonly used in clinics. We performed the prediction interval to virtual screening of azithromycin impurities with high hepatotoxicity and then experimentally confirmed by liver toxicity in zebrafish and c-fos gene expression. Simultaneously, we found the hepatotoxicity of azithromycin impurities may be related to the charge of nitrogen (N) atoms on the side chain group at the C5 position via structure–toxicity relationship of azithromycin impurities with different structures. This study provides a theoretical basis for improvement of the quality of macrolide antibiotics.