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How to facilitate English as a Foreign Language (EFL) interaction in the classroom is one of the key subjects of current research. In this area, interactive teaching has an important impact on EFL second language development, but there are still some gaps in specific teaching methods. Therefore, the aim of this study is to explore how to effectively interact with EFL to improve their second language development under the guidance of scaffolding theory. This study examines two interactive tactics:1) stopping as a communication tactic; 2) scaffolding as an mistake treatment. Besides, this study also reviews two teaching methods including language tasks and willingness to communicate based on scaffolding theory. By analyzing the characteristics of the four strategies, the researcher tries to find out appropriate teaching strategies that could be used, targeting at improving EFL’s second language development. The study shows that error treatment and pausing can broaden EFL’s zone of proximal development (ZPD) and language tasks such as role plays and improving willingness to communicate can facilitate interaction to promote L2 development.

AVRPPHB SUSCEPTIBLE 3 (PBS3) belongs to the GH3 family of acyl acid amido synthetases, which conjugates amino acids to diverse acyl acid substrates. Recent studies demonstrate that PBS3 in Arabidopsis plays a key role in the biosynthesis of plant defense hormone salicylic acid (SA) by catalyzing the conjugation of glutamate to isochorismate to form isochorismate-9-glutamate, which is then used to produce SA through spontaneous decay or ENHANCED PSEUDOMONAS SUSCEPTIBILITY (EPS1) catalysis. Consistent with its function as an essential enzyme for SA biosynthesis, PBS3 is well known to be a positive regulator of plant immunity in Arabidopsis. Additionally, PBS3 is also involved in the trade-off between abiotic and biotic stress responses in Arabidopsis by suppressing the inhibitory effect of abscisic acid on SA-mediated plant immunity. Besides stress responses, PBS3 also plays a role in plant development. Under long-day conditions, PBS3 influences Arabidopsis flowering time by regulating the expression of flowering regulators FLOWERING LOCUS C and FLOWERING LOCUS T. Taken together, PBS3 functions in the signaling network of plant development and responses to biotic and/or abiotic stresses, but the molecular mechanisms underlying its diverse roles remain obscure.

The safety issues and lower energy density of the lithium metal batteries are the two main challenges that hinder their applications in the fields of electric vehicles and portable devices. In this work, the semi-interpenetrated polyvinylidene fluoride-hexafluoropropylene (PVdF-HFP)-based gel polymer electrolyte was synthesized through UV-curing method by employing the ethoxylated trimethylolpropane triacrylate (ETPTA) monomer. The semi-interpenetrating networks formed by polymerization of ETPTA and the high liquid absorption rate of the PVdF-HFP impart the as-prepared electrolyte with a high room temperature ionic conductivity of 3.17 × 10−3 s cm−1 and a high mechanical strength of 3.46 MPa. LiFePO4 was selected as cathode materials, and the active material loading of the cathode is about 4.2 mg cm−2. The electrolyte shows superior long-term cycling properties (127 mAh g−1 after 200 cycles at 0.5 C), excellent rate performance (113 mAh g−1 at 1 C, 80 mAh g−1 at 2 C, and the discharge capacity of 135 mAh g−1 can be restored when the rate goes back to 0.1 C) as well as good ability to inhibit the growth of lithium dendrite (about 150 h). The facile synthesis strategy and great electrochemical performance of the electrolyte make it a potential candidate for lithium metal batteries.

Decoration with alien atoms and increasing the edge content are two valid ways to activate the oxygen reduction reaction (ORR) property of nanocarbons. To further enhance their intrinsic activity and explore the underlying ORR mechanism, graphene nanoribbons (GNRs) were selected as an ideal catalyst model. Theoretical simulations have predicted that with the synergistic effect between heteroatom-doping and edge sites, the ORR activity can be significantly improved. Inspired by this, N-GNRs were synthesized via the oxidative unzipping of CNTs followed by nitrogen incorporation with urea. Ample edges and nitrogen doping sites were detected by high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy, respectively. As a result, N-GNRs exhibited remarkably higher ORR properties in terms of onset and half-wave potentials, Tafel slopes, electron transfer number and methanol tolerance than either GNRs, the control sample without doping, or N-CNTs, the control sample without abundant edges, simply clarifying the significance of synergy between dopants and edges. Thus, this work provides a simple but efficient strategy to fabricate high-performance oxygen reduction catalysts.

By transferring knowledge from a source domain, the performance of deep clustering on an unlabeled target domain can be improved. When achieving this, traditional approaches make the assumption that adequate amount of labeled data is available in a source domain. However, this assumption is usually unrealistic in practice. The source domain should be carefully selected to share some characteristics with the target domain, and it can not be guaranteed that rich labeled samples are always available in the selected source domain.We propose a novel framework to improve deep clustering by transferring knowledge from a source domain without any labeled data. To select reliable instances in the source domain for transferring, we propose a novel adaptive threshold algorithm to select low entropy instances. To transfer important features of the selected instances, we propose a feature-level domain adaptation network (FeatureDA) which cancels unstable generation process. With extensive experiments, we validate that our method effectively improves deep clustering, without using any labeled data in the source domain. Besides, without using any labeled data in the source domain, our method achieves competitive results, compared to the state-of-the-art methods using labeled data in the source domain.

A self-standing, flexible and lithium dendrite growth-suppressing composite gel polymer electrolyte membrane was designed for the use of room-temperature lithium ion batteries. The multi-functional composite semi-interpenetrating polymer network (referred to as “Cs-IPN”) electrolyte membrane was fabricated by combining a UV-cured ethoxylated trimethylolpropane triacrylate (ETPTA) macromer with alumina nanoparticles in the presence of liquid electrolyte and thermoplastic linear poly(ethylene oxide) (PEO). The polymer electrolyte membrane exhibits a semi-interpenetrating polymer network structure and a higher room temperature ionic conductivity, which impart the electrolyte with a significant cycling (120 mAh g−1 after 200 cycles) and a remarkable rate (137 mAh g−1 at 0.1 °C, 130 mAh g−1 at 0.5 °C, 119 mAh g−1 at 1 °C and 100 mAh g−1 at 2 °C) performance in Li/LiFePO4 battery. More importantly, the polymer electrolyte possesses superior ability to inhibit the growth of lithium dendrites, which makes it promising for next generation lithium ion batteries. Keywords: Gel polymer electrolytes, Semi-interpenetrating polymer network, UV-Cured reaction, Ionic conductivity, Lithium ion batteries

Iron-nitrogen-carbon graphitic (Fe-N-C), a noble metal-free catalyst holds a lot of promise to substitute platinum (Pt) as an efficient catalyst in the oxygen reduction reaction (ORR). However, the synthesis process and the stabilization of single atoms that tend to aggregate, without jeopardizing the catalytic activity remain challenging. Here we demonstrate a stabilized assisted method for the preparation of Fe-N-C electrocatalyst by using graphitic carbon nitride (g-C3N4) nanosheet as a template. Fe ions are absorbed on the surface of g-C3N4 and imprisoned after the addition of pyrrole, preventing Fe migration that may result in nanoparticles. During the pyrolysis, Fe atoms coordinated with N provided by g-C3N4 and pyrrole on graphitic carbon to form Fe-N-C with a metal loading of 5.4 wt%. Moreover, FeNx species were introduced in the graphitic carbon, where the coexistence of micro and mesopores were favorable to offer a larger density of active sites compared to Fe/NP without pyrrole. Fe-N-C demonstrated a good electrocatalytic performance with a half-wave potential (E 1/2) of 0.82 V (vs reversible hydrogen electrode (RHE)) higher than Fe/NP (0.76 V) and close to Pt/C, with a superior long stability of 85% in alkaline media after 40000 s.

Time-lapse live cell imaging of a growing cell population is routine in many biological investigations. A major challenge in imaging analysis is accurate segmentation, a process to define the boundaries of cells based on raw image data. Current segmentation methods relying on single boundary features have problems in robustness when dealing with inhomogeneous foci which invariably happens in cell population imaging. Here, we demonstrated that combined with multi-layer training set strategy, a neural-network-based algorithm Cellbow can achieve accurate and robust segmentation of cells in broad and general settings. It can also facilitate long-term tracking of cell growth and division. Furthermore, Cellbow is customizable and generalizable. It is broadly applicable to segmenting fluorescent images of diverse cell types with no further training needed. For bright-field images, only a small set of sample images of the specific cell type from the user may be needed for training. To facilitate the application of Cellbow, we provide a website on which one can online test the software, as well as an ImageJ plugin for the user to visualize the performance before software installation.

CO2-based mixture is a potential working fluid choice of combined cooling and power cycle (CCP) due to its superior thermodynamic performances and the removal of the limit of CO2 critical temperature. This study proposes a CCP system using CO2-based mixtures, loaded on a refrigerated truck, to realize multi-mode transformations for diverse cooling and power demands. The components of mixtures are strictly screened and key parameter analyses and optimization in terms of energy, exergy, adjustability, and economic performance are conducted to find the general laws and the best composition of the mixtures. The results show CO2-based mixtures have better energy-saving potential, adaptability, adjustability, and compactness than CO2. By comparison, CO2/R32 is recommended for superior output capacity, lower operation parameters, remarkable adjustability, and cheaper investment cost. CCP using CO2/R32 can maximally achieve 6.9% power enhancement or 5.9 times cooling enhancement relative to the refrigerated truck using a stand-alone refrigerator, and 19% power increase or 80% cooling increase relative to the CO2 system. It can realize smooth and steady mode transformation to achieve complex and diverse allocation of refrigeration and power in actual operation.

Practical, high-yield mesoporous organic polymer (MOP) spheres were successfully synthesized by a novel self-template method, which can be used as fillers to prepare poly (ethylene oxide) (PEO)-based polymer electrolytes membranes. The result shows that both the electrical conductivity and lithium-ion conductivity of PEO-based electrolytes can be improved effectively by adding the MOP filler. The electrolyte membranes are mechanically robust, thermally stable to over 270 °C, and can effectively block dendrites penetrating from metallic-lithium anode to cathode. The Li+ transfer conductivity of composite electrolyte membrane increases to 4.4 × 10−4 S cm−1 at 63 °C. All-solid-state LiFePO4/MOP-PEO-LiTFSI/Li cell shows excellent cycling (144 mAh g−1 after 300 cycles) and rate (167 mAh g−1 at 0.2 C, 170 mAh g−1 at 0.5 C, 160 mAh g−1 at 1 C and 145 mAh g−1 at 2 C) performance.

Root endophytic fungi that live with plants in a mutualistic fashion could be promising biological agents to improve biotic resistance and plant growth. In this study, 71 endophytic fungi isolates were obtained from blueberry roots, and they were grouped into 2 phyla, 6 classes, 8 orders, and 16 genera based on characterization of morphological features and variances of ITS1, ITS2, and 5.8s nrDNA sequences. Diaporthe and Fusarium were the most abundant genera. Among them, 16 strains exhibited various levels of antagonicstic abilities against five blueberry pathogens including Botrytis cinerea, Phomopsis sp., Botryosphaeria dothidea, Pestalotiopsis sp., and Fusarium oxysporum. The isolate FLR13, which was classified as Pezicula sp., exhibited the strongest level of antifungal effect (>60%) against these five pathogens and displayed potential biological control effect against Botrytis cinerea in blueberry seedlings. In addition, FLR13 could form typical microsclerotia of dark septate endophyte (DSE) in blueberry root cells to evidently enhance blueberry growth, resulting in the significant increases of 24.13% in height, 88.10% in leaf size, 43.32% in stem diameter, and 54.19% in fresh plant weight as compared with non-FLR13 colonized seedlings. Those results suggest that FLR13 should have potential application in disease control and plant growth enhancement.

The gel polymer electrolytes have attracted great attention due to their potential in uniform deposition of lithium, formation of stable SEI, nontoxicity, non-flammability and no leakage. In this work, the PVdF-HFP based gel polymer electrolytes are synthesized by UV-curing method, and the PEGMA and PEGDA are employed to enhance the mechanical properties of the electrolyte by forming 3D semi-interpenetrating polymer network. The PVdF-based gel polymer electrolyte with high ionic conductivity of 4.13 × 10−3 s/cm at room temperature shows superior cycling (140mAh g−1 at 0.5C after 200 cycles) and rate performance (142 mAh g−1 at 0.1C, 123 mAh g−1 at 1C and 90 mAh g−1 at 2C) when LiFePO4 is used as cathode materials. Moreover, the PVdF-based gel polymer electrolyte displays promising performance under high voltage when the NCM523 is selected as cathode materials (136mAh g−1 at 0.5C after 50 cycles). The excellent electrochemical performance as well as high ionic conductivity of the electrolyte may be ascribed to the remarkable liquid absorbing ratio of PVdF-HFP and the 3D cross-linking structure with semi-interpenetrating polymer network formed during UV-curing process.