51 research outputs found
A meta-analysis examining technology-assisted L2 vocabulary learning
This meta-analysis examines the effectiveness of technology-assisted second language (L2) vocabulary learning as well as identifies factors that may play a role in their effectiveness. We found 34 studies with 2,511 participants yielding 49 separate effect sizes. Following the procedure developed by Hunter and Schmidt (2004), we corrected for sample size bias and measurement error. The overall effect size for using technology to learn L2 vocabulary was d = 0.64, which is a moderate effect size. The Q statistic indicated a significant variability in effect size, so we followed up with a theory-driven moderator analysis. The results of the moderator analysis revealed that learners benefited more from technology-assisted L2 vocabulary learning with incidental instruction than with intentional instruction; types of assessment were not significant moderators of the effect on technology-assisted L2 vocabulary learning; technology-assisted L2 vocabulary learning is more effective when the target language is close to the learner’s first language; college students benefited more from technology-assisted L2 vocabulary learning than K–12 students; and, finally, mobile-assisted L2 vocabulary learning was more effective than computer-assisted L2 vocabulary learning
Experimental study on flue gas foam-assisted steam flooding: investigating characteristics of enhanced oil recovery and gas storage
Steam flooding is one of the most widely used heavy oil thermal recovery technologies. Steam transfers heat to heavy oil to reduce viscosity and improve fluidity. The current problem is that steam loses a lot of heat in the formation, and there are serious carbon emissions in the whole production process. In this paper, flue gas and steam were combined to drive heavy oil in the form of composite thermal fluid, and foam was added on this basis. With the help of one-dimensional sandpack model, both single-model and parallel dual-model with permeability ratio experiments were conducted to investigate key characteristics such as steam heat transfer, heavy oil production and flue gas retention during the displacement process. The experimental results indicated that flue gas effectively inhibited steam condensation and reduced heat loss during the flow process. Compared to steam flooding, the sandpack model exhibited temperature rises of 4.4°C and 9.1°C at the middle and end, respectively. While flue gas foam fell slightly short of flue gas in terms of enhanced heat transfer, it outperforms in recovery factor, achieving a 10.4% improvement over flue gas-assisted steam flooding. The foam blocked gas channeling by accumulating and capturing along the flow path, resulting in a gas retention volume of 389 mL within the model. Furthermore, the flue gas foam facilitated steam flow to previously unswept low-permeability areas, thus enhancing oil recovery. In the parallel double-model experiment, the low-permeability model exhibited significantly improved oil displacement efficiency compared to flue gas-assisted steam flooding, and the remaining oil content in the end of the high permeability model was increased by 1.9%, while the remaining oil content in the front and end of the low-permeability model was reduced by 3.5% and 3.8% respectively
Production status and research advancement on root rot disease of faba bean (Vicia faba L.) in China
China is the largest producer of faba bean with a total harvested area of 8.11Ă—105 ha and a total production of 1.69 Ă—106 tons (dry beans) in 2020, accounting for 30% of the world production. Faba bean is grown in China for both fresh pods and dry seed. East China cultivates large seed cultivars for food processing and fresh vegetables, while northwestern and southwestern China grow cultivars for dry seeds, with an increased production of fresh green pods. Most of the faba bean is consumed domestically, with limited exports. The absence of unified quality control measures and simple traditional cultivation practices contributes to the lower competitiveness of the faba bean industry in international markets. Recently, new cultivation methods have emerged with improved weed control, as well as better water and drainage management, resulting in higher quality and income for producers. Root rot disease in faba bean is caused by multiple pathogens, including Fusarium spp., Rhizoctonia spp., and Pythium spp. Fusarium spp. is the most prevalent species causing root rot in faba bean crops and is responsible for severe yield loss, with different species causing the disease in different regions in China. The yield loss ranges from 5% to 30%, up to 100% in severely infected fields. The management of faba bean root rot disease in China involves a combination of physical, chemical, and bio-control methods, including intercropping with non-host crops, applying rational nitrogen, and treating seeds with chemical or bio-seed treatments. However, the effectiveness of these methods is limited due to the high cost, the broad host range of the pathogens, and potential negative impacts on the environment and non-targeted soil organisms. Intercropping is the most widely utilized and economically friendly control method to date. This review provides an overview of the current status of faba bean production in China, the challenges faced by the industry due to root rot disease, and the progress in identifying and managing this disease. This information is critical for developing integrated management strategies to effectively control root rot in faba bean cultivation and facilitating the high-quality development of the faba bean industry
Integrated transcriptomics and metabolomics analysis provide insight into the resistance response of rice against brown planthopper
IntroductionThe brown planthopper (Nilaparvata lugens StĂĄl, BPH) is one of the most economically significant pests of rice. The Bph30 gene has been successfully cloned and conferred rice with broad-spectrum resistance to BPH. However, the molecular mechanisms by which Bph30 enhances resistance to BPH remain poorly understood.MethodsHere, we conducted a transcriptomic and metabolomic analysis of Bph30-transgenic (BPH30T) and BPH-susceptible Nipponbare plants to elucidate the response of Bph30 to BPH infestation.ResultsTranscriptomic analyses revealed that the pathway of plant hormone signal transduction enriched exclusively in Nipponbare, and the greatest number of differentially expressed genes (DEGs) were involved in indole 3-acetic acid (IAA) signal transduction. Analysis of differentially accumulated metabolites (DAMs) revealed that DAMs involved in the amino acids and derivatives category were down-regulated in BPH30T plants following BPH feeding, and the great majority of DAMs in flavonoids category displayed the trend of increasing in BPH30T plants; the opposite pattern was observed in Nipponbare plants. Combined transcriptomics and metabolomics analysis revealed that the pathways of amino acids biosynthesis, plant hormone signal transduction, phenylpropanoid biosynthesis and flavonoid biosynthesis were enriched. The content of IAA significantly decreased in BPH30T plants following BPH feeding, and the content of IAA remained unchanged in Nipponbare. The exogenous application of IAA weakened the BPH resistance conferred by Bph30.DiscussionOur results indicated that Bph30 might coordinate the movement of primary and secondary metabolites and hormones in plants via the shikimate pathway to enhance the resistance of rice to BPH. Our results have important reference significance for the resistance mechanisms analysis and the efficient utilization of major BPH-resistance genes
Identification and validation of G protein-coupled receptors modulating flow-dependent signaling pathways in vascular endothelial cells
Vascular endothelial cells are exposed to mechanical forces due to their presence at the interface between the vessel wall and flowing blood. The patterns of these mechanical forces (laminar vs. turbulent) regulate endothelial cell function and play an important role in determining endothelial phenotype and ultimately cardiovascular health. One of the key transcriptional mediators of the positive effects of laminar flow patterns on endothelial cell phenotype is the zinc-finger transcription factor, krĂĽppel-like factor 2 (KLF2). Given its importance in maintaining a healthy endothelium, we sought to identify endothelial regulators of the KLF2 transcriptional program as potential new therapeutic approaches to treating cardiovascular disease. Using an approach that utilized both bioinformatics and targeted gene knockdown, we identified endothelial GPCRs capable of modulating KLF2 expression. Genetic screening using siRNAs directed to these GPCRs identified 12 potential GPCR targets that could modulate the KLF2 program, including a subset capable of regulating flow-induced KLF2 expression in primary endothelial cells. Among these targets, we describe the ability of several GPCRs (GPR116, SSTR3, GPR101, LGR4) to affect KLF2 transcriptional activation. We also identify these targets as potential validated targets for the development of novel treatments targeting the endothelium. Finally, we highlight the initiation of drug discovery efforts for LGR4 and report the identification of the first known synthetic ligands to this receptor as a proof-of-concept for pathway-directed phenotypic screening to identify novel drug targets
Understanding Information Technology Acceptance and Effectiveness in College Students\u27 English Learning in China
The current research aims to collect facts to reveal an objective and a general understanding about the factors that predict Chinese college students\u27 technology use in learning English and the correlation between the technology use and students\u27 English learning achievement. Based on the research objectives, a quantitative correlational methodological approach is chosen to explore critical factors of technology use behavior of Chinese college students in learning English. The current study adopted the UTAUT model to explore the acceptance of digital technology in English learning by college students in mainland China and adopted the CET4 and CET6 score to demonstrate Chinese college students\u27 English learning performance. Structural Equation Modeling was used in the current research. This research found that Perceived Usefulness and Social Norms predict students\u27 technology use intention. Students\u27 use intentions and Teachers\u27 Technology Use significantly impact students technology use. Teachers\u27 technology use positively correlates with students\u27 English proficiency score in CET4 and CET6. Students autonomous technology use positively correlates students\u27 English proficiency score in CET6. These findings highlighted the importance of technology use in College English teaching and learning
Understanding Information Technology Acceptance and Effectiveness in College Students\u27 English Learning in China
The current research aims to collect facts to reveal an objective and a general understanding about the factors that predict Chinese college students\u27 technology use in learning English and the correlation between the technology use and students\u27 English learning achievement. Based on the research objectives, a quantitative correlational methodological approach is chosen to explore critical factors of technology use behavior of Chinese college students in learning English. The current study adopted the UTAUT model to explore the acceptance of digital technology in English learning by college students in mainland China and adopted the CET4 and CET6 score to demonstrate Chinese college students\u27 English learning performance. Structural Equation Modeling was used in the current research. This research found that Perceived Usefulness and Social Norms predict students\u27 technology use intention. Students\u27 use intentions and Teachers\u27 Technology Use significantly impact students technology use. Teachers\u27 technology use positively correlates with students\u27 English proficiency score in CET4 and CET6. Students autonomous technology use positively correlates students\u27 English proficiency score in CET6. These findings highlighted the importance of technology use in College English teaching and learning
Association between sunlight exposure and risk of age-related macular degeneration: a meta-analysis
Abstract Background A substantial number of epidemiological studies have investigated the possible associations between sunlight exposure and Age-related Macular Degeneration (AMD), but the results from studies are inconsistent. The aim of this meta-analysis was to evaluate the association between sunlight exposure and the risk of AMD. Methods Relevant studies were searched using databases including PubMed, EMBASE, and Web of Science database. Two authors independently extracted data and assessed study quality. The random-effects model was used to calculate the pooled covariates-adjusted odds ratio (OR). Subgroup analyses based on study design, stage of AMD, method of exposure assessment, and study latitude were carried out. The heterogeneity across the studies was tested, as was publication bias. Results Fourteen eligible studies including 43,934 individuals based on the inclusion criteria were analyzed. The pooled OR for sunlight exposure and AMD was 1.10 (95% CI = 0.98–1.23). In addition, similar insignificant results were observed in further subgroup analyses based on stage of AMD, method of exposure assessment, and study latitude. Sun-avoidance behavior did not decrease the risk of AMD (OR = 1.12, 95% CI = 0.76–1.67). Moderate heterogeneity was observed in most of analyses. Conclusion The results indicate that sunlight exposure may not be associated with increased risk of AMD based on current published data
Achieving High Performance Molecular Rectification through Fast Screening Alkanethiol Carboxylate-Metal Complexes Electro-Active Unites
Achieving high rectifying performance of molecular scale diode devices through synthetic chemistry and device construction remain a formidable challenge due to the complexity of the charge transport process and the device structure. We demonstrated here high-performance molecular rectification realized in self-assembled monolayer (SAM) based device by low-cost and fast screening the electroactive units. SAMs of commercial available carboxylate terminated alkane thiols on gold substrate, coordinated with a variety of metal ions, structures denoting as Au-S-(CH2)n-1COO-Mm+ (Cn+Mm+), where n=11, 12, 13, 14, 16, 18 and Mm+=Ca2+, Mn2+, Fe2+,
Fe3+, Co2+, Ni2+, Cu2+, Zn2+, were prepared and junctions were measured using a eutectic indiumgallium alloy top contact (EGaIn). The C18+Ca2+ and C18+Zn2+ junctions were found to afford a record high rectification ratio (RR) of 756 at ±1.5 V. Theoretical analysis based on single level
tunneling model shows that optimized combination of the asymmetry voltage division, energy barrier and the coupling of carboxylate-metal complex with electrode. Our method described here represent a general strategy for fast, cheap and effective exploration of the metal complex chemical space for high-performance molecular diodes devices
The Water Status in China and an Adaptive Governance Frame for Water Management
China is increasingly facing water-related problems, such as water scarcity, pollution, and overexploitation of groundwater. This paper discusses the water status in China and claims that governance is the cause of water-related problems. The structure of the current water management is analyzed to conclude that the control-command is a static approach which is less capable of dealing with the uncertainty in the water resources system. An adaptive governance frame is introduced, which highlights the learning process and participation. The learning process avoids making the same mistake twice and the participation ensures the diversity of information, which are both necessary for water resources management
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