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This study investigated the influence of microbead dosages (0, 5, 10, 15, and 20%) on the frost resistance of expanded polystyrene (EPS) concrete. Five groups of EPS concrete specimens were prepared and subjected to rapid freeze–thaw tests. The freeze–thaw deterioration of EPS concrete was assessed using macroscopic indicators, including mass loss, strength loss, and dynamic elastic modulus loss. The underlying deterioration mechanism was revealed through the analysis of the EPS particle–matrix interface. A concrete damage plasticity model of EPS concrete based on damage mechanics theory was established. The results indicate that the addition of microbeads increased the strength of EPS concrete by 38–53%, reduced the strength attenuation after freeze–thaw damage by 8.1%, and improved the frost resistance level by 10–60 grades. The optimal dosage of microbeads is 15% of the cementitious material. The interfacial transition zone gaps in EPS concrete with added microbeads after freeze–thaw cycles are smaller, contributing to a more complete hydration reaction. The freeze–thaw damage model established in this study accurately reflects the freeze–thaw damage law of EPS concrete and provides a reference for studying the mechanical properties of EPS concrete under freeze–thaw cycles. The research findings of this study can enhance the strength and service life of EPS concrete, expanding its application scope as a structural material. The study provides valuable insights for future research and engineering applications related to the frost resistance of EPS concrete.

ObjectiveChlorophyll fluorescence (ChlF) emission from photosystem II (PSII) is closely coupled with photochemical reactions. As an efficient and non-destructive means of obtaining plant photosynthesis efficiency and physiological state information, the collection of fluorescence signals is often used in many fields such as plant physiological research, smart agricultural information sensing, etc. Chlorophyll fluorescence imaging systems, which is the experimental device for collecting the fluorescence signal, have difficulties in application due to their high price and complex structure. In order to solve the issues, this paper investigates and constructs a low-cost chlorophyll fluorescence imaging system based on a micro complementary metal oxide semiconductor (CMOS) camera and a smartphone, and carries out experimental verifications and applications on it.MethodThe chlorophyll fluorescence imaging system is mainly composed of three parts: excitation light, CMOS camera and its control circuit, and a upper computer based on a smartphone. The light source of the excitation light group is based on the principle and characteristics of chlorophyll fluorescence, and uses a blue light source of 460 nm band to achieve the best fluorescence excitation effect. In terms of structure, the principle of integrating sphere was borrowed, the bowl-shaped light source structure was adopted, and the design of the LED surface light source was used to meet the requirements of chlorophyll fluorescence signal measurement for the uniformity of the excitation light field. For the adjustment of light source intensity, the control scheme of pulse width modulation was adopted, which could realize sequential control of different intensities of excitation light. Through the simulation analysis of the light field, the light intensity and distribution characteristics of the light field were stuidied, and the calibration of the excitation light group was completed according to the simulation results. The OV5640 micro CMOS camera was used to collect fluorescence images. Combined with the imaging principle of the CMOS camera, the fluorescence imaging intensity of the CMOS camera was calculated, and its ability to collect chlorophyll fluorescence was analyzed and discussed. The control circuit of the CMOS camera uses an STM32 microcontroller as the microcontroller unit, and completes the data communication between the synchronous light group control circuit and the smartphone through the RS232 to TTL serial communication module and the full-speed universal serial bus, respectively. The smartphone upper computer software is the operating software of the chlorophyll fluorescence imaging system user terminal and the overall control program for fluorescence image acquisition. The overall workflow could be summarized as the user sets the relevant excitation light parameters and camera shooting instructions in the upper computer as needed, sends the instructions to the control circuit through the universal serial bus and serial port, and completes the control of excitation light and CMOS camera image acquisition. After the chlorophyll fluorescence image collection was completed, the data would be sent back to the smart phone or server for analysis, processing, storage, and display. In order to verify the design of the proposed scheme, a prototype of the chlorophyll fluorescence imaging system based on this scheme was made for experimental verification. Firstly, the uniformity of the light field was measured on the excitation light to test the actual performance of the excitation light designed in this article. On this basis, a chlorophyll fluorescence imaging experiment under continuous light excitation and modulated pulse light protocols was completed. Through the analysis and processing of the experimental results and comparison with mainstream chlorophyll fluorometers, the fluorescence imaging capabilities and low-cost advantages of this chlorophyll fluorometer were further verified.Results and DiscussionsThe maximum excitation light intensity of the chlorophyll fluorescence imaging system designed in this article was 6250 µmol/(m2·s). Through the simulation analysis of the light field and the calculation and analysis of the fluorescence imaging intensity of the CMOS camera, the feasibility of collecting chlorophyll fluorescence images by the OV5640 micro CMOS camera was demonstrated, which provided a basis for the specific design and implementation of the fluorometer. In terms of hardware circuits, it made full use of the software and hardware advantages of smartphones, and only consisted of the control circuits of the excitation light and CMOS camera and the corresponding communication modules to complete the fluorescence image collection work, simplifying the circuit structure and reducing hardware costs to the greatest extent. The final fluorescence instrument achieved a collection resolution of 5 million pixels, a spectral range of 400~1000 nm, and a stable acquisition frequency of up to 42 f/s. Experimental results showed that the measured data was consistent with theoretical analysis and simulation, which could meet the requirements of fluorescence detection. The instrument was capable of collecting images of chlorophyll fluorescence under continuous light excitation or the protocol of modulated pulsed light. The acquired chlorophyll fluorescence images could reflect the two-dimensional heterogeneity of leaves and could effectively distinguish the photosynthetic characteristics of different leaves. Typical chlorophyll fluorescence parameter images of Fv/Fm, Rfd, etc. were in line with expectations. Compared with the existing chlorophyll fluorescence imaging system, the chlorophyll fluorescence imaging system designed in this article has obvious cost advantages while realizing the rapid detection function of chlorophyll fluorescence.ConclusionsThe instrument is with a simple structure and low cost, and has good application value for the detection of plant physiology and environmental changes. The system is useful for developing other fluorescence instruments.

To meet the requirements of miniaturization and low power consumption of portable instruments, a set of lower computer control system of portable quadrupole mass spectrometry was designed. The new control system was developed based on Xilinx spartan-6 series field programmable gate array (FPGA) platform. A single FPGA chip was used to replace the cumbersome architecture of traditional multiple chip combinations. The original W5500\MCU\DSP\DDR and other functional chips on the main control circuit board were removed, and the scanning, control, acquisition, storage, data processing, high-speed transmission and other functions realized by these chips were integrated into the same FPGA chip. The control system mainly communicated with the lower computer through the upper computer. The lower computer controlled the DAC voltage to scan the quadrupole, and at the same time linked the 16 bit ADC to collect data. The collected data was processed by some columns of algorithms, and then a large amount of data was accumulated and compressed, stored in the chip. Finally, the whole spectrum data was integrated according to the frame format and uploaded to the upper computer for displaying. The lower computer control system also integrated tuning control, feedback control, high voltage control and other functional modules. The difficulty in the design of the whole system lied in the high utilization of chip resources, which required a reasonable allocation of various chip resources and a balance in performance, speed and area. Compared with the existing miniaturized quadrupole mass spectrometry control system, the new control system not only saved the chip cost on the premise of unchanged function and performance, but also saved about 2.7 W in the power consumption of the master hardware board, which was about 37% of the power consumption of the original board, and reduced about 20 cm2 in the area of the master hardware board, which was about 10% of the area of the original board. The performance of the portable quadrupole mass spectrometer lower computer control system was fully verified by the 25 volatile organic compounds (VOCs) mixed standard test experiment, and was successfully applied in the portable quadrupole mass spectrometer. This design has high technology portability and practical value for similar miniaturized instruments. At this stage of the design, it is not possible to integrate all the functions of the instrument and realize a real single-chip lower computer control system, and the integrated functional modules need to be further optimized. Under the demand of miniaturization and low power consumption of portable instruments, the concept and design of integration will go further and further, and will slowly and truly achieve simple substitution for cumbersome, single substitution for combination, so as to make the concept of portability to the extreme and obtain the maximum value with the least consumption.

The traditional named entity disambiguation technology usually relies on rich context and knowledge of external entities. However, many emerging entities lack knowledge bases and the text containing entities is short. These limitations make traditional algorithms unable to make full use of contextual semantic information. At the same time,due to the limitation of the number of effective samples, the final application scenarios of the algorithm are very limited. Based on the above defects, this paper proposes a deep learning-based entity disambiguation method combining bidirectional encoder representation from transformers(BERT) model and long short-term memory neural network.The main work are the following parts: 1) A word vector based on the BERT model is designed to obtain more information through fewer data samples. 2) In order to allow the long short-term memory neural networks to retain useful information and verify that the short text applies to the method of this article, this method segments the sentence samples. 3) This article uses the neural network intelligence(NNI) technology proposed by Microsoft, which makes it possible to quickly and efficiently obtain the optimal neural network hyperparameter. This study compares other different types of word vectors and neural network technology, confirming that the F-Measure value of the entity disambiguation technology based on deep learning used in this paper is higher.

ABSTRACT Anopheles mosquitoes are the primary vectors for the transmission of malaria parasites, which poses a devastating burden on global public health and welfare. The recent invasion of Anopheles stephensi in Africa has made malaria eradication more challenging due to its outdoor biting behavior and widespread resistance to insecticides. To address this issue, we developed a new approach for mosquito larvae control using gut microbiota-mediated RNA interference (RNAi). We engineered a mosquito symbiotic gut bacterium, Serratia fonticola, by deleting its RNase III gene to produce double-stranded RNAs (dsRNAs) in the mosquito larval gut. We found that the engineered S. fonticola strains can stably colonize mosquito larval guts and produce dsRNAs dsMet or dsEcR to activate RNAi and effectively suppress the expression of methoprene-tolerant gene Met and ecdysone receptor gene EcR, which encode receptors for juvenile hormone and ecdysone pathways in mosquitoes, respectively. Importantly, the engineered S. fonticola strains markedly inhibit the development of A. stephensi larvae and leads to a high mortality, providing an effective dsRNA delivery system for silencing genes in insects and a novel RNAi-mediated pest control strategy. Collectively, our symbiont-mediated RNAi (smRNAi) approach offers an innovative and sustainable method for controlling mosquito larvae and provides a promising strategy for combating malaria. IMPORTANCE Mosquitoes are vectors for various diseases, imposing a significant threat to public health globally. The recent invasion of A. stephensi in Africa has made malaria eradication more challenging due to its outdoor biting behavior and widespread resistance to insecticides. RNA interference (RNAi) is a promising approach that uses dsRNA to silence specific genes in pests. This study presents the use of a gut symbiotic bacterium, Serratia fonticola, as an efficient delivery system of dsRNA for RNAi-mediated pest control. The knockout of RNase III, a dsRNA-specific endonuclease gene, in S. fonticola using CRISPR-Cas9 led to efficient dsRNA production. Engineered strains of S. fonticola can colonize the mosquito larval gut and effectively suppress the expression of two critical genes, Met and EcR, which inhibit mosquito development and cause high mortality in mosquito larvae. This study highlights the potential of exploring the mosquito microbiota as a source of dsRNA for RNAi-based pest control.

Purpose This study explores the achievements and process of a group of Chinese primary school teachers learning from a research-based school–university collaborative project. Design/Approach/Methods We used qualitative methods to construct our research design, collecting data through participatory observations of weekly meetings, teacher interviews, and participants’ reflective journals. Both thematic analysis and discursive analysis were employed as strategies to scrutinize the data. Findings We categorize teachers’ learning into five achievements: outcome, processual, democratic, catalytic, and dialogic achievement. A further examination highlights seven successive learning actions composing an implicit mechanism to facilitate these achievements: questioning, analyzing, modeling, examining, implementing, reflecting, and consolidating. Originality/Value Through this longitudinal study, we more comprehensively record details about teachers’ learning as they conduct their own research. Although school–university heterogeneous collaboration has potential conflicts, teachers can improve their problem-solving and knowledge creation and sharing abilities, promoting a sense of professional accomplishment. These findings also suggest the need to reconsider the authentic process of teacher research, a task equally significant for international educators.

Abstract Background Microparticles (MPs) are extracellular vesicles that are associated with cancer development and progression. Advanced non-small cell lung cancer (NSCLC) still shows disease progression after multiple lines of treatment. Therefore, the objective of this study was to explore the correlation between circulating MPs and disease progression in advanced NSCLC, and to find a new method for concise and rapid determination of disease progression. Methods Patients with advanced NSCLC admitted to hospital between October 2019 and October 2020 were included and divided into objective remission (OR) and progressive disease (PD) groups. The morphology of MPs was observed using transmission electron microscopy. The circulating total MPs, neutrophil MPs (NMPs), and platelet MPs (PMPs) before and after treatment were detected by flow cytometry, and a predictive model for disease progression in advanced NSCLC was developed. Results Eighty-six patients were included; 60 in the OR group and 26 in the PD group. There was no significant difference in total MPs, NMPs, or PMPs at baseline between the two groups. After treatment, total MPs, NMPs, and PMPs were significantly higher in the PD than those in the OR group. Multivariate regression analysis showed that post-treatment NMPs≥160 events/μL(OR,3.748;95%CI,1.147–12.253,p = 0.029), PMPs≥80 events/μL(OR,10.968;95%CI,2.973–40.462,p < 0.0001) and neutrophil/lymphocyte ratio (NLR) ≥3.3 (OR,4.929;95%CI,1.483–16.375,p = 0.009) were independently associated with progression of advanced NSCLC. Post-treatment NMPs and PMPs combined with NLR were used to build a predictive model for progression of advanced NSCLC. The area under the curve was 0.825 (95%CI,0.715–0.934, p < 0.0001), optimal cut-off value was 16, sensitivity was 80.8%, and specificity was 88.3%. Conclusion NMPs and PMPs are associated with progression of advanced NSCLC. The predictive model for progression of advanced NSCLC, established combining NMPs, PMPs, and NLR, can screen out 80.8% of patients with PD. This is helpful for real-time accurate, concise and rapid assessment of disease progression and timely adjustment of drug therapy. Trial registration Chinese Clinical Trial Registry, ChiCTR1800020223 . Registered 20 December 2018, http://www.chictr.org.cn/index.aspx .

This study was to explore the bibliometric characteristics of TPACK from 2011 to 2020. By using the keyword “TPACK,” the bibliographic references have been retrieved from the Scopus databases (date of search: March 7, 2021). The VOSviewr software tool and Bibliometrix R package were used for information analysis. The results confirmed that there are 700 articles, representing 63 countries and 159 journals scanned. Articles in 2013 were cited the most times, and since 2016, the number of articles is on the rise every year. The United States, Turkey, and Australia were the three leading countries in this field. Most of the articles were published in educational technology journals. The total articles published by American institutions are more than the others, followed by Asian institutions. The most prolific authors are all Asians, followed by Americans. Core themes from the highly cited articles have been surrounding PCK, teacher education, skill, and pedagogy. The development of TPACK has gradually turned to practical strategies and tried to find strategic ways to facilitate teachers to implement technology-assisted teaching.

This narrative inquiry explores three Chinese university leaders' intercultural competence as a key dimension of their leadership that overseas leadership development programmes enabled them to develop. The leaders visited three different countries -- namely, the United States, the United Kingdom and Canada -- storied their experiences in the programmes and connected their reflections to leadership in the Chinese higher education system. Our narrative analyses show that the overseas leadership development programmes were mediators in the construction of leadership, for which there were two focal themes: (1) leadership as a personal and contextual construction process and (2) intercultural competence as a key dimension of university leaders' leadership. Betwixt and between different higher education systems in different cultural contexts, the reconceptualisation of leadership with intercultural competence is unfurled in the liminal space, which goes beyond the functionalist paradigm of leadership and is also of international interest and value in the global communication of higher education.

Abstract Many biology-based precision drugs are available that neutralize aberrant molecular pathways in cancer. Molecular heterogeneity and the lack of reliable companion diagnostic biomarkers for many drugs makes targeted treatment of cancer inaccurate for many individuals. Identifying actionable hyperactive biological pathways in individual cancers may improve this situation. To achieve this we applied a novel targeted RNA next generation sequencing (t/RNA-NGS) technique to surgically obtained glioma tissues. The test combines mutation detection with analysis of biological pathway activities that are involved in tumour behavior in many cancer types (e.g. tyrosine kinase signaling, angiogenesis signaling, immune response, metabolism), via quantitative measurement of transcript levels and splice variants of hundreds of genes. We here present proof of concept that the technique, which uses molecular inversion probes, generates a histology-independent molecular diagnosis and identifies classifiers that are strongly associated with conventional histopathology diagnoses and even with patient prognosis. The test not only confirmed known glioma-associated molecular aberrations but also identified aberrant expression levels of actionable genes and mutations that have so far been considered not to be associated with glioma, opening up the possibility of drug repurposing for individual patients. Its cost-effectiveness makes t/RNA-NGS to an attractive instrument to aid oncologists in therapy decision making.

Abstract Acute pancreatitis (AP) is a common acute abdominal disease, 10–20% of which can evolve into severe AP (SAP) causing significant morbidity and mortality. Bone marrow-derived mesenchymal stem cells (BMSCs) have the potential of repairing SAP, but the detailed mechanism remains unknown. We demonstrate here that microRNA-9 (miR-9) modified BMSCs (pri-miR-9-BMSCs) can significantly reduce the pancreatic edema, infiltration, hemorrhage, necrosis, the release of amylase and lipase. Meanwhile, decreased local/systemic inflammatory response (TNF-α↓, IL-1β↓, IL-6↓, HMGB1↓, MPO↓, CD68↓, IL-4↑, IL-10↑, and TGF-β↑) and enhanced regeneration of damaged pancreas (Reg4↑, PTF1↑, and PDX1↑) are also promoted. But these effects diminish or disappear after antagonizing miR-9 (TuD). Besides, we find that miR-9 is negatively correlated with AP and miR-9 agomir which can mimic the effects of pri-miR-9-BMSCs and protect injured pancreas. Furthermore, we investigate that BMSCs deliver miR-9 to the injured pancreas or peripheral blood mononuclear cell (PBMC), which can target the NF-κB1/p50 gene and inhibit the NF-κB signaling pathway (p-P65↓, NF-κB1/p50↓, IκBα↑, IκBβ↑). Taken together, these results show that miR-9 is a key paracrine factor of BMSCs attenuating SAP targeting the NF-κB1/p50 gene and suppressing the NF-κB signaling pathway.

This study aims to discuss and analyze Finnish and Chinese primary school teachers’ practices when digital storytelling is the teaching method, aiming for student-generated stories in video format. To meet this end, teachers introduce digital storytelling in their practices and guide and support students into building and sharing digital stories in video format with peers in the classroom and online. In addition, they introduce the use of web-based environments and digital technologies, adapt their teaching plan accordingly, and enrich existing instructional material. As a result, teacher’s practices of organizing and facilitating student work and development change. In order to investigate how teaching practices change, this study draws from Chinese and Finnish teachers’ interviews and observation data and uses inductive analysis and constant comparison for more abstract themes and categories. The findings show that the teachers use formal and informal, natural and technological environments to organize student work and aim for freer learning in digital storytelling activities. Also, different aspects of collaborative work are used to facilitate and, mainly, structure student work and development.

OBJECTIVE:To evaluate the effect of ShenQi FuZheng Injection (SFI) on cellular immunity and clinical efficacy in patients with advanced non small cell lung cancer(NSCLC) when combined with chemotherapy. METHODS:Electronic databases including EMBASE, PUBMED, the conference proceedings of the American Society of Clinical Oncology (ASCO), Cochrane, Chinese National Knowledge Infrastructure (CNKI), and Chinese Biological Medical disc(CBM) were searched, until July, 2015. The randomized controlled clinical studies reporting results of efficacy and immune function were collected according to the inclusion criteria. Cochrane handbook 5.1.0 was applied to assess the quality of included trials and Revman 5 software was used for data analysis. RESULTS:Fifteen studies including 1006 cases of advanced NSCLC were included based on the inclusion criteria. The results of meta-analysis showed that there were significant differences in percentages of CD3+ cells (SMD = 13.48; 95%CI: 8.11-18.85; p