Abstract Exploring English intelligibility in linguistically diverse environments, such as China, is crucial for improving cross-cultural dialog and tailoring language instruction to address the ...phonetic hurdles of non-native speakers. This research employed a phonetic experimental methodology to assess the intelligibility of English spoken by college students from the Bashu dialect region of Southwest China to an international audience. Data from 40 intermediate English-proficient students in Sichuan and Chongqing were analyzed using open-ended questionnaires and evaluative scales. The findings revealed that the influence of the Bashu dialect significantly impeded the accurate articulation of specific English phonemes, thereby exerting an impact on the international intelligibility of their spoken English. Notably, notwithstanding their conspicuous accents, the research concluded that the English enunciated by these students generally retained intelligibility for global audiences. The study identified a spectrum of pronunciation challenges, encompassing issues with phonetic sounds, recurrent mispronunciations, and variances in accent and prosody, collectively contributing to an overarching influence on intelligibility. Grounded in international listener feedback, this study proffers strategies to augment the intelligibility of spoken English among Chinese learners originating from dialect-specific regions, thereby fostering the amelioration of their communicative skills and bolstering their confidence when engaging with global audiences.
As a 100% atom-economy process, direct oxidation of methane into methanol remains as a grand challenge due to the dilemma between activation of methane and over-oxidation of methanol. Here, we report ...that water enabled mild oxidation of methane into methanol with >99% selectivity over Au single atoms on black phosphorus (Au
/BP) nanosheets under light irradiation. The mass activity of Au
/BP nanosheets reached 113.5 μmol g
in water pressured with 33 bar of mixed gas (CH
:O
= 10:1) at 90 °C under light irradiation (1.2 W), while the activation energy was 43.4 kJ mol
. Mechanistic studies revealed that water assisted the activation of O
to generate reactive hydroxyl groups and •OH radicals under light irradiation. Hydroxyl groups reacted with methane at Au single atoms to form water and CH
* species, followed by oxidation of CH
* via •OH radicals into methanol. Considering the recycling of water during the whole process, we can also regard water as a catalyst.
Abstract
Development of excellent and cheap electrocatalysts for water electrolysis is of great significance for application of hydrogen energy. Here, we show a highly efficient and stable oxygen ...evolution reaction (OER) catalyst with multilayer-stacked hybrid structure, in which vertical graphene nanosheets (VGSs), MoS
2
nanosheets, and layered FeCoNi hydroxides (FeCoNi(OH)
x
) are successively grown on carbon fibers (CF/VGSs/MoS
2
/FeCoNi(OH)
x
). The catalyst exhibits excellent OER performance with a low overpotential of 225 and 241 mV to attain 500 and 1000 mA cm
−2
and small Tafel slope of 29.2 mV dec
−1
. Theoretical calculation indicates that compositing of FeCoNi(OH)
x
with MoS
2
could generate favorable electronic structure and decrease the OER overpotential, promoting the electrocatalytic activity. An alkaline water electrolyzer is established using CF/VGSs/MoS
2
/FeCoNi(OH)
x
anode for overall water splitting, which generates a current density of 100 mA cm
−2
at 1.59 V with excellent stability over 100 h. Our highly efficient catalysts have great prospect for water electrolysis.
Antimicrobial efficacy, which is central to many aspects of medicine, is being rapidly eroded by bacterial resistance. Since new resistance can be induced by antimicrobial action, highly lethal ...agents that rapidly reduce bacterial burden during infection should help restrict the emergence of resistance. To improve lethal activity, recent work has focused on toxic reactive oxygen species (ROS) as part of the bactericidal activity of diverse antimicrobials. We report that when Escherichia coli was subjected to antimicrobial stress and the stressor was subsequently removed, both ROS accumulation and cell death continued to occur. Blocking ROS accumulation by exogenous mitigating agents slowed or inhibited poststressor death. Similar results were obtained with a temperature-sensitive mutational inhibition of DNA replication. Thus, bacteria exposed to lethal stressors may not die during treatment, as has long been thought; instead, death can occur after plating on drug-free agar due to poststress ROS-mediated toxicity. Examples are described in which (i) primary stress-mediated damage was insufficient to kill bacteria due to repair; (ii) ROS over-came repair (i.e., protection from anti-ROS agents was reduced by repair deficiencies); and (iii) killing was reduced by anti-oxidative stress genes acting before stress exposure. Enzymatic suppression of poststress ROS-mediated lethality by exogenous catalase supports a causal rather than a coincidental role for ROS in stress-mediated lethality, thereby countering challenges to ROS involvement in anti-microbial killing. We conclude that for a variety of stressors, lethal action derives, at least in part, from stimulation of a self-amplifying accumulation of ROS that overwhelms the repair of primary damage.
Single-atom catalysts (SACs) exhibit intriguing catalytic performance owing to their maximized atom utilizations and unique electronic structures. However, the reported strategies for synthesizing ...SACs generally have special requirements for either the anchored metals or the supports. Herein, we report a universal approach of electrochemical deposition that is applicable to a wide range of metals and supports for the fabrication of SACs. The depositions were conducted on both cathode and anode, where the different redox reactions endowed the SACs with distinct electronic states. The SACs from cathodic deposition exhibited high activities towards hydrogen evolution reaction, while those from anodic deposition were highly active towards oxygen evolution reaction. When cathodically- and anodically-deposited Ir single atoms on Co
Fe
Se
@Ni foam were integrated into a two-electrode cell for overall water splitting, a voltage of 1.39 V was required at 10 mA cm
in alkaline electrolyte.
Numerous studies have highlighted that long non-coding RNAs (lncRNAs) can bind to microRNA (miRNA) sites as competing endogenous RNAs (ceRNAs), thereby affecting and regulating the expression of ...mRNAs and target genes. These lncRNA-associated ceRNAs have been theorized to play a significant role in cancer initiation and progression. However, the roles and functions of the lncRNA-miRNA-mRNA ceRNA network in squamous cell carcinoma of the tongue (SCCT) are still unclear.
The miRNA, mRNA and lncRNA expression profiles from 138 patients with SCCT were downloaded from The Cancer Genome Atlas database. We identified the differential expression of miRNAs, mRNAs, and lncRNAs using the limma package of R software. We used the clusterProfiler package for GO and KEGG pathway annotations. The survival package was used to estimate survival analysis according to the Kaplan-Meier curve. Finally, the GDCRNATools package was used to construct the lncRNA-miRNA-mRNA ceRNA network.
In total, 1943 SCCT-specific mRNAs, 107 lncRNAs and 100 miRNAs were explored. Ten mRNAs (CSRP2, CKS2, ADGRG6, MB21D1, GMNN, RIPOR3, RAD51, PCLAF, ORC1, NAGS), 9 lncRNAs (LINC02560, HOXC13 - AS, FOXD2 - AS1, AC105277.1, AC099850.3, STARD4 - AS1, SLC16A1 - AS1, MIR503HG, MIR100HG) and 8 miRNAs (miR - 654, miR - 503, miR - 450a, miR - 379, miR - 369, miR - 190a, miR - 101, and let-7c) were found to be significantly associated with overall survival (log-rank p < 0.05). Based on the analysis of the lncRNA-miRNA-mRNA ceRNA network, one differentially expressed (DE) lncRNA, five DEmiRNAs, and three DEmRNAs were demonstrated to be related to the pathogenesis of SCCT.
In this study, we described the gene regulation by the lncRNA-miRNA-mRNA ceRNA network in the progression of SCCT. We propose a new lncRNA-associated ceRNA that could help in the diagnosis and treatment of SCCT.
We have evaluated the catalytic properties of Au-based nanostructures (including nanocages, nanoboxes, and solid nanoparticles) using a model reaction based on the reduction of p-nitrophenol by ...NaBH4. From the average reaction rate constants at three different temperatures, we determined the activation energy, the entropy of activation, and the pre-exponential factor for each type of Au nanostructure. The kinetic data indicate that the Au-based nanocages are catalytically more active than both the nanoboxes and nanoparticles probably due to their extremely thin but electrically continuous walls, the high content of Au, and the accessibility of both inner and outer surfaces through the pores in the walls. In addition, a compensation effect was observed in this Au-based catalytic system, which can be primarily interpreted by a model based on kinetic regime switching.
The homogeneity of single-atom catalysts is only to the first-order approximation when all isolated metal centers interact identically with the support. Since the realistic support with various ...topologies or defects offers diverse coordination environments, realizing real homogeneity requires precise control over the anchoring sites. In this work, we selectively anchor Ir single atoms onto the three-fold hollow sites (Ir
/T
-CoOOH) and oxygen vacancies (Ir
/V
-CoOOH) on defective CoOOH surface to investigate how the anchoring sites modulate catalytic performance. The oxygen evolution activities of Ir
/T
-CoOOH and Ir
/V
-CoOOH are improved relative to CoOOH through different mechanisms. For Ir
/T
-CoOOH, the strong electronic interaction between single-atom Ir and the support modifies the electronic structure of the active center for stronger electronic affinity to intermediates. For Ir
/V
-CoOOH, a hydrogen bonding is formed between the coordinated oxygen of single-atom Ir center and the oxygenated intermediates, which stabilizes the intermediates and lowers the energy barrier of the rate-determining step.
Professional identity has become a central topic in teacher education research and a crucial factor in shaping teachers' self-perception and perspectives on various aspects of their profession, ...including teacher roles, scholarly research, curriculum design, classroom instruction, instructional methods, and strategies, as well as their interactions within the educational context. Despite the considerable scholarly interest in teacher identity development, relatively few studies have considered how to measure teacher professional identity. This study developed and validated a new measurement of professional identity among Chinese pre-service teachers from an English language education program. A total of 560 pre-service teachers majoring in English language education were invited to participate in a survey and 542 questionnaires were deemed valid and subjected to analysis. Through this analysis, a scale with 17 items was developed, focusing on three different dimensions: professional self-efficacy, career commitment, and professional knowledge. After excluding items with a relatively poor correlation with factor loading, the final scale consisted of 13 items. The results showed that the developed scale has relatively good reliability (α = 0.939) and structural validity (χ2/df = 2.46, p < .001, CFI = 0.978, TLI = 0.971, SRMR = 0.033, RMSEA (90% CI) = 0.071 0.054, 0.089). This study may provide a quantitative instrument for future research to measure professional identity among pre-service teachers, both in Chinese and other contexts.
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