437 research outputs found
The Process of English Language Teaching and Learning experienced by Teachers and Students in Two Contexts: China and New Zealand
This study investigated the process of tertiary English language teaching and learning as experienced by teachers of English as a foreign language (EFL) and English as a second language (ESL) and their Chinese EFL and ESL students in the two contexts: China and New Zealand. Specifically, it explored classroom practice in terms of six key perspectives: instructional approaches, language pedagogy, use of textbooks, student modalities, error correction and classroom tasks by means of questionnaires, the Adapted Communicative Orientation of Language Teaching (COLT) Observation Scheme, stimulated recall interviews (SRIs) and interviews.
Data for this study were collected from six regular scheduled lessons randomly selected and videotaped in the two tertiary contexts, as well as from the perspectives of 120 Chinese students (104 EFL and 16 ESL) and their 6 teachers (3 in each context) who experienced and/or viewed these videotaped lessons.
This thesis uses three theoretical strands: (1) English language teaching (ELT) contexts - definitions and distinguishing EFL and ESL; (2) ELT approaches - the Grammar-Translation method (GTM), Communicative Language Teaching (CLT) and the Task-Based Language Teaching (TBLT); and (3) ELT classroom practice - instructional approaches, language pedagogy, use of textbooks, student modality, error correction and classroom tasks. It revisits the background of Chinese traditional educational culture and its influences on Chinese English education, discusses the GTM and CLT in the Chinese EFL context, and covers the literature on ELT classroom practice in both contexts. These strands are used in theorizing the current research.
This research aims to enable the views of Chinese EFL and ESL tertiary students and their EFL and ESL teachers on ELT in these two contexts to be heard or studied. It is an attempt to better comprehend the various factors which might aid or hinder the development of Chinese EFL and ESL students' English communicative competence in these English language classes. This includes addressing how EFL and ESL teachers might best help their Chinese students to achieve communicative competence in the classroom setting and which teaching approaches are the most effective in doing so.
The findings showed that a conventional teacher-centred instructional approach continues to have considerable purchase for Chinese EFL and ESL students in both contexts. The findings suggest that it is important and also necessary, to some extent, to have teacher-centred instruction and grammar teaching according to students' needs and students' language levels. Nonetheless, it also revealed that the Chinese ESL students who shared the same Chinese culture and English education background as the Chinese EFL students had different perspectives on classroom tasks conducted in the Chinese EFL context after they experienced the Western English education for a short time in New Zealand. Another finding of this study was that age-appropriateness should be taken into consideration by ESL teachers when they design their classroom tasks for Chinese ESL tertiary students
Catalytic oxidation of phenol in wastewater — A new application of the amorphous Fe78Si9B13 alloy
Identification and characterization of two critical sequences in SV40PolyA that activate the green fluorescent protein reporter gene
Alu repeats or Line-1-ORF2 (ORF2) inhibit expression of the green fluorescent protein (GFP) gene when inserted downstream of this gene in the vector pEGFP-C1. In this work, we studied cis-acting elements that eliminated the repression of GFP gene expression induced by Alu and ORF2 and sequence characteristics of these elements. We found that sense and antisense PolyA of simian virus 40 (SV40PolyA, 240 bp) eliminated the repression of GFP gene expression when inserted between the GFP gene and the Alu (283 bp) repeats or ORF2 (3825 bp) in pAlu14 (14 tandem Alu repeats were inserted downstream of the GFP gene in the vector pEGFP-C1) or pORF2. Antisense SV40PolyA (PolyAas) induced stronger gene expression than its sense orientation (PolyA). Of four 60-bp segments of PolyAas (1F1R, 2F2R, 3F3R and 4F4R) inserted independently into pAlu14, only two (2F2R and 3F3R) eliminated the inhibition of GFP gene expression induced by Alu repeats. Deletion analysis revealed that a 17 nucleotide AT repeat (17ntAT; 5′-AAAAAAATGCTTTATTT-3′) in 2F2R and the fragment 3F38d9 (5′-ATAAACAAGTTAACAACA ACAATTGCATT-3′) in 3F3R were critical sequences for activating the GFP gene. Sequence and structural analyses showed that 17ntAT and 3F38d9 included imperfect palindromes and may form a variety of unstable stem-loops. We suggest that the presence of imperfect palindromes and unstable stem-loops in DNA enhancer elements plays an important role in GFP gene activation
Why Does Advice Discounting Occur? The Combined Roles of Confidence and Trust
Judges tend to discount the opinions of others even though advice is often helpful in improving their accuracy. The present research proposes that this phenomenon of advice discounting results from the judges’ confidence in their initial decision and little trust in advice. Furthermore, the degree of advice discounting may be predicted by the combined roles of confidence and trust. Three studies provide evidence for these hypotheses. Participants were very confident in their initial estimation and had little trust in the advice (study 1). The degree of advice discounting decreased when participants felt less confidence in performing difficult tasks compared with easy tasks (study 2) or when participants placed more trust in advice because the advice was from an expert rather than from a novice (study 3). In addition, confidence and trust predicted the degree of advice discounting across three studies. These findings shed new light on the mechanism underlying advice discounting and advice taking by indicating the combined roles of confidence and trust
Transpositional reactivation of the Dart transposon family in rice lines derived from introgressive hybridization with Zizania latifolia
<p>Abstract</p> <p>Background</p> <p>It is widely recognized that interspecific hybridization may induce "genome shock", and lead to genetic and epigenetic instabilities in the resultant hybrids and/or backcrossed introgressants. A prominent component involved in the genome shock is reactivation of cryptic transposable elements (TEs) in the hybrid genome, which is often associated with alteration in the elements' epigenetic modifications like cytosine DNA methylation. We have previously reported that introgressants derived from hybridization between <it>Oryza sativa </it>(rice) and <it>Zizania latifolia </it>manifested substantial methylation re-patterning and rampant mobilization of two TEs, a <it>copia </it>retrotransposon <it>Tos17 </it>and a MITE <it>mPing</it>. It was not known however whether other types of TEs had also been transpositionally reactivated in these introgressants, their relevance to alteration in cytosine methylation, and their impact on expression of adjacent cellular genes.</p> <p>Results</p> <p>We document in this study that the <it>Dart </it>TE family was transpositionally reactivated followed by stabilization in all three studied introgressants (RZ1, RZ2 and RZ35) derived from introgressive hybridization between rice (cv. Matsumae) and <it>Z. latifolia</it>, while the TEs remained quiescent in the recipient rice genome. Transposon-display (TD) and sequencing verified the element's mobility and mapped the excisions and re-insertions to the rice chromosomes. Methylation-sensitive Southern blotting showed that the <it>Dart </it>TEs were heavily methylated along their entire length, and moderate alteration in cytosine methylation patterns occurred in the introgressants relative to their rice parental line. Real-time qRT-PCR quantification on the relative transcript abundance of six single-copy genes flanking the newly excised or inserted <it>Dart</it>-related TE copies indicated that whereas marked difference in the expression of all four genes in both tissues (leaf and root) were detected between the introgressants and their rice parental line under both normal and various stress conditions, the difference showed little association with the presence or absence of the newly mobilized <it>Dart-</it>related TEs.</p> <p>Conclusion</p> <p>Introgressive hybridization has induced transpositional reactivation of the otherwise immobile <it>Dart</it>-related TEs in the parental rice line (cv. Matsumae), which was accompanied with a moderate alteration in the element's cytosine methylation. Significant difference in expression of the <it>Dart</it>-adjacent genes occurred between the introgressants and their rice parental line under both normal and various abiotic stress conditions, but the alteration in gene expression was not coupled with the TEs.</p
Collaborative Camouflaged Object Detection: A Large-Scale Dataset and Benchmark
In this paper, we provide a comprehensive study on a new task called
collaborative camouflaged object detection (CoCOD), which aims to
simultaneously detect camouflaged objects with the same properties from a group
of relevant images. To this end, we meticulously construct the first
large-scale dataset, termed CoCOD8K, which consists of 8,528 high-quality and
elaborately selected images with object mask annotations, covering 5
superclasses and 70 subclasses. The dataset spans a wide range of natural and
artificial camouflage scenes with diverse object appearances and backgrounds,
making it a very challenging dataset for CoCOD. Besides, we propose the first
baseline model for CoCOD, named bilateral-branch network (BBNet), which
explores and aggregates co-camouflaged cues within a single image and between
images within a group, respectively, for accurate camouflaged object detection
in given images. This is implemented by an inter-image collaborative feature
exploration (CFE) module, an intra-image object feature search (OFS) module,
and a local-global refinement (LGR) module. We benchmark 18 state-of-the-art
models, including 12 COD algorithms and 6 CoSOD algorithms, on the proposed
CoCOD8K dataset under 5 widely used evaluation metrics. Extensive experiments
demonstrate the effectiveness of the proposed method and the significantly
superior performance compared to other competitors. We hope that our proposed
dataset and model will boost growth in the COD community. The dataset, model,
and results will be available at: https://github.com/zc199823/BBNet--CoCOD.Comment: Accepted by IEEE Transactions on Neural Networks and Learning Systems
(TNNLS
Association of Base Excision Repair Gene Polymorphisms with ESRD Risk in a Chinese Population
The base excision repair (BER) pathway, containing OGG1, MTH1 and MUTYH, is a major protector from oxidative DNA damage in humans, while 8-oxoguanine (8-OHdG), an index of DNA oxidation, is increased in maintenance hemodialysis (HD) patients. Four polymorphisms of BER genes, OGG1 c.977C > G (rs1052133), MTH1 c.247G > A (rs4866), MUTYH c.972G > C (rs3219489), and AluYb8MUTYH (rs10527342), were examined in 337 HD patients and 404 healthy controls. And the 8-OHdG levels in leukocyte DNA were examined in 116 HD patients. The distribution of MUTYH c.972 GG or AluYb8MUTYH differed between the two groups and was associated with a moderately increased risk for end-stage renal disease (ESRD) (P = 0.013 and 0.034, resp.). The average 8-OHdG/106 dG value was significantly higher in patients with the OGG1 c.977G, MUTYH c.972G or AluYb8MUTYH alleles (P < 0.001 via ANOVA). Further analysis showed that combination of MUTYH c.972GG with OGG1 c.977GG or AluYb8MUTYH increased both the risk for ESRD and leukocyte DNA 8-OHdG levels in HD patients. Our study showed that MUTYH c.972GG, AluYb8MUTYH, and combination of OGG1 c.977GG increased the risk for ESRD development in China and suggested that DNA oxidative damage might be involved in such process
Monolayer Excitonic Laser
Recently, two-dimensional (2D) materials have opened a new paradigm for
fundamental physics explorations and device applications. Unlike gapless
graphene, monolayer transition metal dichalcogenide (TMDC) has new optical
functionalities for next generation ultra-compact electronic and
opto-electronic devices. When TMDC crystals are thinned down to monolayers,
they undergo an indirect to direct bandgap transition, making it an outstanding
2D semiconductor. Unique electron valley degree of freedom, strong light matter
interactions and excitonic effects were observed. Enhancement of spontaneous
emission has been reported on TMDC monolayers integrated with photonic crystal
and distributed Bragg reflector microcavities. However, the coherent light
emission from 2D monolayer TMDC has not been demonstrated, mainly due to that
an atomic membrane has limited material gain volume and is lack of optical mode
confinement. Here, we report the first realization of 2D excitonic laser by
embedding monolayer tungsten disulfide (WS2) in a microdisk resonator. Using a
whispering gallery mode (WGM) resonator with a high quality factor and optical
confinement, we observed bright excitonic lasing in visible wavelength. The
Si3N4/WS2/HSQ sandwich configuration provides a strong feedback and mode
overlap with monolayer gain. This demonstration of 2D excitonic laser marks a
major step towards 2D on-chip optoelectronics for high performance optical
communication and computing applications.Comment: 15 pages, 4 figure
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