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1.
Adv Mater ; : e2403489, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38556648

RESUMO

Rechargeable aqueous proton batteries with small organic molecule anodes are currently considered promising candidates for large-scale energy storage due to their low cost, stable safety, and environmental friendliness. However, the practical application is limited by the poor cycling stability caused by the shuttling of soluble organic molecules between electrodes. Herein, a cell separator is modified by a GO-casein-Cu2+ layer with a brick-and-mortar structure to inhibit the shuttling of small organic molecules. Experimental and calculation results indicate that, attributed to the synergistic effect of physical blocking of casein molecular chains and electrostatic and coordination interactions of Cu2+, bulk dissolution and shuttling of multiple small molecules can be inhibited simultaneously, while H+ transfer across the separators is not almost affected. With the protection of the GO-casein-Cu2+ separator, soluble small molecules, such as diquinoxalino[2,3-a:2',3'-c]phenazine,2,3,8,9,14,15-hexacyano (6CN-DQPZ) exhibit a high reversible capacity of 262.6 mA h g-1 and amazing stability (capacity retention of 92.9% after 1000 cycles at 1 A g-1). In addition, this strategy is also proved available to other active conjugated small molecules, such as indanthrone (IDT), providing a general green sustainable strategy for advancing the use of small organic molecule electrodes in proton cells.

2.
Nanomaterials (Basel) ; 14(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38607147

RESUMO

Field emission (FE) necessitates cathode materials with low work function and high thermal and electrical conductivity and stability. To meet these requirements, we developed FE cathodes based on high-quality wrinkled multilayer graphene (MLG) prepared using the bubble-assisted chemical vapor deposition (B-CVD) method and investigated their emission characteristics. The result showed that MLG cathodes prepared using the spin-coating method exhibited a high field emission current density (~7.9 mA/cm2), indicating the excellent intrinsic emission performance of the MLG. However, the weak adhesion between the MLG and the substrate led to the poor stability of the cathode. Screen printing was employed to prepare the cathode to improve stability, and the influence of a silver buffer layer was explored on the cathode's performance. The results demonstrated that these cathodes exhibited better emission stability, and the silver buffer layer further enhanced the comprehensive field emission performance. The optimized cathode possesses low turn-on field strength (~1.5 V/µm), low threshold field strength (~2.65 V/µm), high current density (~10.5 mA/cm2), and good emission uniformity. Moreover, the cathode also exhibits excellent emission stability, with a current fluctuation of only 6.28% during a 4-h test at 1530 V.

3.
Natl Sci Rev ; 11(4): nwae045, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38545446

RESUMO

Organic materials with rich active sites are good candidates of high-capacity anodes in aqueous batteries, but commonly low utilization of active sites limits their capacity. Herein, two isomers, symmetric and asymmetric hexaazatribenzanthraquinone (s-HATBAQ and a-HATBAQ), with rich active sites have been synthesized in a controllable manner. It has been revealed for the first time that a sulfuric acid catalyst can facilitate the stereoselective formation of s-HATBAQ. Attributed to the reduced steric hindrance in favor of proton insertion as well as the amorphous structure conducive to electrochemical dynamics, s-HATBAQ exhibits 1.5 times larger specific capacity than a-HATBAQ. Consequently, the electrode of s-HATBAQ with 50% reduced graphene oxide (s-HATBAQ-50%rGO) delivers a record high specific capacity of 405 mAh g-1 in H2SO4 electrolyte. Moreover, the assembled MnO2//s-HATBAQ-50%rGO aqueous proton full batteries show an exceptional cycling stability at 25°C and can maintain ∼92% capacity after 1000 cycles at 0.5 A g-1 at -80°C. This work demonstrates the controllable synthesis of isomers, showcases a wide-temperature-range prototype proton battery and highlights the significance of precise molecular structure modulation in organic energy storage.

4.
bioRxiv ; 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38328192

RESUMO

Eight of the 24 integrin heterodimers bind to the tripeptide Arg-Gly-Asp (RGD) motif in their extracellular ligands, and play essential roles in cell adhesion, migration, and homeostasis. Despite similarity in recognizing the RGD motif and some redundancy, these integrins can selectively recognize RGD-containing ligands including fibronectin, vitronectin, fibrinogen, nephronectin and the prodomain of the transforming growth factors to fulfill specific functions in cellular processes. Subtype-specific antibodies against RGD-binding integrins are desirable for investigating their specific functions. In this study, we discovered 11 antibodies that exhibit high specificity and affinity towards integrins αVß3, αVß5, αVß6, αVß8, and α5ß1 from a synthetic yeast-displayed Fab library. Of these, 6 are function-blocking antibodies containing an R(G/L/T) D motif in their CDR3 sequences. We report antibody binding specificity, kinetics, and binding affinity for purified integrin ectodomains as well as intact integrins on the cell surface. We further employed these antibodies to reveal binding preferences of the αV subunit for its 5 ß-subunit partners: ß6=ß8>ß3>ß1=ß5.

5.
Front Microbiol ; 15: 1328177, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38419627

RESUMO

African swine fever (ASF) caused by the African swine fever virus (ASFV) is a fatal and highly contagious disease of domestic pigs characterized by rapid disease progression and death within 2 weeks. How the immune cells respond to acute ASFV infection and contribute to the immunopathogenesis of ASFV has not been completely understood. In this study, we examined the activation, apoptosis, and functional changes of distinct immune cells in domestic pigs following acute infection with the ASFV CADC_HN09 strain using multicolor flow cytometry. We found that ASFV infection induced broad apoptosis of DCs, monocytes, neutrophils, and lymphocytes in the peripheral blood of pigs over time. The expression of MHC class II molecule (SLA-DR/DQ) on monocytes and conventional DCs as well as CD21 expression on B cells were downregulated after ASFV infection, implying a potential impairment of antigen presentation and humoral response. Further examination of CD69 and ex vivo expression of IFN-γ on immune cells showed that T cells were transiently activated and expressed IFN-γ as early as 5 days post-infection. However, the capability of T cells to produce cytokines was significantly impaired in the infected pigs when stimulated with mitogen. These results suggest that the adaptive cellular immunity to ASFV might be initiated but later overridden by ASFV-induced immunosuppression. Our study clarified the cell types that were affected by ASFV infection and contributed to lymphopenia, improving our understanding of the immunopathogenesis of ASFV.

6.
Proc Natl Acad Sci U S A ; 120(48): e2309506120, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37983498

RESUMO

African swine fever virus (ASFV), a devastating pathogen to the worldwide swine industry, mainly targets macrophage/monocyte lineage, but how the virus enters host cells has remained unclear. Here, we report that ASFV utilizes apoptotic bodies (ApoBDs) for infection and cell-cell transmission. We show that ASFV induces cell apoptosis of primary porcine alveolar macrophages (PAMs) at the late stage of infection to productively shed ApoBDs that are subsequently swallowed by neighboring PAMs to initiate a secondary infection as evidenced by electron microscopy and live-cell imaging. Interestingly, the virions loaded within ApoBDs are exclusively single-enveloped particles that are devoid of the outer layer of membrane and represent a predominant form produced during late infection. The in vitro purified ApoBD vesicles are capable of mediating virus infection of naive PAMs, but the transmission can be significantly inhibited by blocking the "eat-me" signal phosphatidyserine on the surface of ApoBDs via Annexin V or the efferocytosis receptor TIM4 on the recipient PAMs via anti-TIM4 antibody, whereas overexpression of TIM4 enhances virus infection. The same treatment however did not affect the infection by intracellular viruses. Importantly, the swine sera to ASFV exert no effect on the ApoBD-mediated transmission but can partially act on the virions lacking the outer layer of membrane. Thus, ASFV has evolved to hijack a normal cellular pathway for cell-cell spread to evade host responses.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Vesículas Extracelulares , Suínos , Animais , Vírus da Febre Suína Africana/fisiologia , Macrófagos/metabolismo , Monócitos/metabolismo , Vesículas Extracelulares/metabolismo
8.
Animals (Basel) ; 13(7)2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37048502

RESUMO

African swine fever (ASF) is a devastating infectious disease in domestic pigs caused by African swine fever virus (ASFV) with a mortality rate of about 100%. However, the understanding of the interaction between ASFV and host is still not clear. In this study, the expression differences and functional analysis of microRNA (miRNA) in porcine peripheral blood lymphocytes of ASFV infected pigs and healthy pigs were compared based on Illumina high-throughput sequencing, then the GO and KEGG signal pathways were analyzed. The miRNA related to immunity and inflammation were screened, and the regulatory network of miRNA-mRNA was drawn. A total of 70 differentially expressed miRNAs were found (p ≤ 0.05). Of these, 45 were upregulated and 25 were downregulated in ASFV-infected pigs vs. healthy pigs. A total of 8179 mRNA genes targeted by these 70 differentially expressed miRNA were predicted, of which 1447 mRNA genes were targeted by ssc-miR-2320-5p. Five differentially expressed miRNA were validated by RT-qPCR, which were consistent with the RNA-Seq results. The GO analysis revealed that a total of 30 gene functions were significantly enriched, including 7 molecular functions (MF), 13 cellular components (CC), and 10 biological processes (BP). The KEGG enrichment analysis revealed that the differentially expressed genes were significantly enriched in pathways related to immunity, inflammation, and various metabolic processes, in which a total of two downregulated miRNAs after infection and eight upregulated miRNAs related to immunity and inflammation were screened in ASFV-infected pigs vs. healthy pigs. The network of miRNA-mRNA showed that the mRNA target genes were strongly regulated by ssc-miR-214, ssc-miR-199b-3p, and ssc-miR-199a-3p. The mRNA target genes were enriched into the MAPK signaling pathway, Toll-like receptor signaling pathway, TNF signaling pathway, and IL-17 signaling pathway by using a KEGG enrichment analysis. Therefore, ASFV could regulate immunity and metabolism-related pathways in infected pigs by inducing differential expression of miRNAs. These results provided a new basis for further elucidating the interactions between ASFV and the host as well as the immunity regulation mechanisms of ASFV, which will be conducive to better controlling ASF.

9.
Brain Res ; 1803: 148230, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36608758

RESUMO

This event-related potentials study explored the processing of Mandarin short passives. We used a syntactic violation paradigm to compare the processing of two auxiliary phrases (i.e., a verb-modifier di-phrase and a noun-modifier de-phrase). In the control condition, the syntactic hierarchy of the di-phrase was lower than that of the de-phrase. In the violation condition, the low-level violation was created by replacing di with de in the auxiliary phrase, while the high-level violation was created by replacing de with di in the auxiliary phrase. The ERP data showed that the noun-modifier elicited the greater left anterior negativity (LAN) and the P600 than the verb-modifier, in both the control condition and the violation condition. We also observed that the LAN induced by the verb-modifier phrase was greater in the control condition than that in the violation condition, while the LAN induced by the noun-modifier was greater in the violation condition than that in the control condition. These results suggested that the greater cortical LAN-P600 might differentiate the high-level hierarchy from the low-level hierarchy. In addition, we tentatively claimed that given the same predicate argument structure, long passives might be the default representational mode of short passives (generally, a constructional alternation might be activated during the processing of the target structure).


Assuntos
Compreensão , Semântica , Compreensão/fisiologia , Idioma , Potenciais Evocados/fisiologia , Inibidores de Proteínas Quinases , Eletroencefalografia
10.
Environ Sci Pollut Res Int ; 30(15): 45295-45314, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36705829

RESUMO

Low-cost and underutilized plant fibers can affect the mechanical behavior of cementitious materials such as cemented tailings backfill (CTB). This paper attempts to explore the mechanical properties and damage evolution characteristics of rice straw fiber (RFS)-reinforced CTB (RSFCTB) from the perspective of energy. A series of mechanical and microscopic tests were carried out on CTB and RSFCTB samples. On this basis, the energy evolution law and of the filling body under different stress paths were analyzed. Meanwhile, a damage variable based on dissipation energy was established, and the damage evolution process of the filling body was discussed. The results show that uniaxial compressive strength (UCS) of filling body first grew and then dropped with the enhancement of RSF content, and indirect tensile strength (ITS) was positively correlated with RSF content. Scanning electron microscope showed that RSF was encapsulated by hydration products, which promoted the bridging effect of RSF. The bridging effect of RSF improved the integrity of RSFCTB after compression failure and resulted in bending and asymmetric tensile cracks after tensile failure. The energy storage limit and dissipation energy of the filling body under different stress paths were enhanced due to the incorporation of RSF. The damage curve based on dissipation energy showed three stages of slow, steady, and fast damage under compressive loading. The damage curve of RSFCTB was located below CTB depending on the crack arresting effect of RSF. Moreover, the damage curve under tensile load shows three stages: slow, stable damage, and sudden increase in damage. The damage value of RSFCTB at the mutation point was increased, and the ability of RSFCTB to resist tensile damage was enhanced. The energy evolution and acoustic emission parameters were combined, and their development trends were similar, which proved that it was reasonable to characterize the damage of filling body based on the dissipated energy.


Assuntos
Oryza , Acústica , Força Compressiva , Mutação , Estruturas Vegetais
11.
Small ; 19(16): e2207487, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36693783

RESUMO

Benefiting from the proton's small size and ultrahigh mobility in water, aqueous proton batteries are regarded as an attractive candidate for high-power and ultralow-temperature energy storage devices. Herein, a new-type C4 N polymer with uniform micropores and a large specific surface area is prepared by sulfuric acid-catalyzed ketone amine condensation reaction and employed as the electrode of proton batteries. Multi-walled carbon nanotubes (MWCNT) are introduced to induce the in situ growth of C4 N, and reaped significantly enhanced porosity and conductivity, and thus better both room- and low-temperature performance. When coupled with MnO2 @Carbon fiber (MnO2 @CF) cathode, MnO2 @CF//C4 N-50% MWCNT full battery shows unprecedented cycle stability with a capacity retention of 98% after 11 000 cycles at 10 A g-1 and even 100% after 70 000 cycles at 20 A g-1 . Additionally, a novel anti-freezing electrolyte (5 m H2 SO4  + 0.5 m MnSO4 ) is developed and showed a high ionic conductivity of 123.2 mS cm-1 at -70 °C. The resultant MnO2 @CF//C4 N-50% MWCNT battery delivers a specific capacity of 110.5 mAh g-1 even at -70 °C at 1 A g-1 , the highest in all reported proton batteries under the same conditions. This work is expected to offer a package solution for constructing high-performance ultralow-temperature aqueous proton batteries.

12.
Environ Sci Pollut Res Int ; 30(9): 24687-24707, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36346525

RESUMO

The mechanical characteristics of cemented paste backfill (CPB) are significantly influenced by the loading rate (LR) and initial defects. Therefore, the CPB with prefabricated fracture (PF, PFCPB) was prepared, and uniaxial compressive strength (UCS) tests considering LR and acoustic emission (AE) monitoring were performed. The particle flow code (PFC2D) was introduced to analyze the mesoscopic crack evolution of the filling body, and the moment tensor theory was used to invert the AE signals characteristics. The results show that as the PF angle increased, the UCS and elastic modulus (EM) of PFCPB decreased and then increased, and the 30° PF was the turning point. The mechanical properties of PFCPB were deteriorated by the presence of PF. Meanwhile, the mechanical properties of PFCPB were positively correlated with the LR. The stress-strain curve of PFCB (excluding 90°) showed bimodal curves. After the UCS test, the macro crack of PFCPB sprouted at the tip of PF or converged toward PF. PFCPB mainly suffered from shear failure, accompanied by a few tensile failures. Numerical simulation results showed that the crack initiation stress of PFCPB was reduced by the PF. The number of cracks first dropped and then gradually increased when the PF angle was enhanced, while gradually increased with the LR increased. Meanwhile, the mesoscopic AE characteristics of CPB were strongly in line with the test results. The AE events of 0 ~ 60° PFCPB experienced two slow rising periods and rapid rising periods. The temporal and spatial distribution characteristics of AE corresponded to the crack evolution trend. The PF was prone to stress concentration, especially at the tip and upper and lower surfaces of 0 ~ 45° PF, resulting in rapid crack initiation and reducing the energy storage limit and mechanical behavior of 0 ~ 45° PFCPB. The increasing LR (within a certain range) was in favor of improving the mechanical behavior of the filling body. The research results can provide a basic reference for the stability evaluation of the filling body with initial defects.


Assuntos
Acústica , Ansiedade , Força Compressiva
13.
Nat Commun ; 13(1): 7471, 2022 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463259

RESUMO

Although integrins are known to be mechanosensitive and to possess many subtypes that have distinct physiological roles, single molecule studies of force exertion have thus far been limited to RGD-binding integrins. Here, we show that integrin α4ß1 and RGD-binding integrins (αVß1 and α5ß1) require markedly different tension thresholds to support cell spreading. Furthermore, actin assembled downstream of α4ß1 forms cross-linked networks in circularly spread cells, is in rapid retrograde flow, and exerts low forces from actin polymerization. In contrast, actin assembled downstream of αVß1 forms stress fibers linking focal adhesions in elongated cells, is in slow retrograde flow, and matures to exert high forces (>54-pN) via myosin II. Conformational activation of both integrins occurs below 12-pN, suggesting that post-activation subtype-specific cytoskeletal remodeling imposes the higher threshold for spreading on RGD substrates. Multiple layers of single integrin mechanics for activation, mechanotransduction and cytoskeleton remodeling revealed here may underlie subtype-dependence of diverse processes such as somite formation and durotaxis.


Assuntos
Actinas , Integrina beta1 , Mecanotransdução Celular , Integrina alfa4beta1 , Oligopeptídeos
14.
Environ Sci Pollut Res Int ; 29(60): 90686-90702, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35870070

RESUMO

The cemented paste backfill (CPB) has a significant loading rate (LR) effect. The damage evolution process of CPB is closely related to the characteristics of acoustic emission (AE). This paper analyzes the damage evolution law of the filling body under different loading rates using indoor test and numerical simulations. We introduce the moment tensor theory to simulate the AE characteristics of the whole process of filling loading and explore the LR effect of the backfill with the help of the energy conservation. The results indicate the following: (1) when LR increases from 0.1 to 2 mm/min, the UCS of the backfill first increases and then decreases, contributing to the occurance of the critical LR. (2) There are no microcracks occurred in the backfill at the initial stage of loading, and the microcracks increase slowly, which is not obviously affected by LR. After the peak value, the microcracks in backfill expand and propagat rapidly to form mesoscopic cracks. (3) The mesoscopic AE events based on the moment tensor theory are in good agreement with the laboratory tests results, which can be divided into the initial period, quiet period, slow raising period, rapid raising period, and rapid falling period. (4) The temporal and spatial distribution characteristics of AE are consistent with the evolution law of microcracks. There are fewer AE events before the peak value, and AE events increase significantly and frequently with large magnitude events after the peak value. AE events dense zone and AE events with larger magnitude increase under higher LR. (5) Besides, the boundary energy and dissipation energy also gradually increased; at the same time, the strain energy first increased and then decreased. The results can provide a reference for understanding the damage evolution characteristics of backfill by different LR and AE mesoscopic simulation.


Assuntos
Acústica
15.
Viruses ; 14(6)2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35746813

RESUMO

The CD69 molecule, as an early activation marker of lymphocytes, is often used to assess the activation of cellular immunity. However, for pigs, an anti-pig CD69 antibody is not yet available for this purpose after infection or vaccination. In this study, a monoclonal antibody (mAb) against pig CD69 was produced by peptide immunization and hybridoma technique. One mAb (5F12) showed good reactivity with pig CD69 that was expressed in transfected-HEK-293T cells and on mitogen-activated porcine peripheral blood mononuclear cells (PBMCs) by indirect immunofluorescence assay and flow cytometry. This mAb did not cross-react with activated lymphocytes from mouse, bovine, and chicken. Epitope mapping showed that the epitope recognized by this mAb was located at amino acid residues 147-161 of pig CD69. By conjugating with fluorochrome, this mAb was used to detect the early activation of lymphocytes in PRRSV- and ASFV-infected pigs by flow cytometry. The results showed that PRRSV infection induced the dominant activation of CD4 T cells in mediastinal lymph nodes and CD8 T cells in the spleen at 14 days post-infection, in terms of CD69 expression. In an experiment on ASFV infection, we found that ASFV infection resulted in the early activation of NK cells, B cells, and distinct T cell subsets with variable magnitude in PBMCs, spleen, and submandibular lymph nodes. Our study revealed an early event of lymphocyte and T cell activation after PRRSV and ASFV infections and provides an important immunological tool for the in-depth analysis of cellular immune response in pigs after infection or vaccination.


Assuntos
Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Animais , Anticorpos Monoclonais/metabolismo , Bovinos , Leucócitos Mononucleares , Ativação Linfocitária , Camundongos , Síndrome Respiratória e Reprodutiva Suína/metabolismo , Suínos
16.
Brain Sci ; 12(5)2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35624911

RESUMO

Previous studies on the neural cognitive mechanisms of aspectual processing in second language (L2) learners have focused on Indo-European languages with rich inflectional morphology. These languages have aspects which are equipped with inflected verb forms combined with auxiliary or modal verbs. Meanwhile, little attention has been paid to Mandarin Chinese, which has limited morphological inflection, and its aspect is equipped with aspectual particles (e.g., le, zhe, guo). The present study explores the neurocognitive mechanism of Mandarin Chinese aspect processing among two groups of late Mandarin Chinese proficient learners with Thai (with Mandarin Chinese-like aspect markers) and Indonesian (lack of Mandarin Chinese-like aspect markers) as their first language (L1). We measured event-related potentials (ERPs) time locked to the aspect marker le in two different conditions (the aspect violation sentences and the correct sentences). A triphasic ELAN-LAN-P600 effect was produced by the Mandarin Chinese native speakers. However, there was no ELAN and LAN in Indonesian native speakers and Thai native speakers, except a 300-500 ms negativity widely distributed in the right hemisphere and P600-like effect. This suggests that both groups of Mandarin Chinese learners cannot reach the same level as Mandarin Chinese native speakers to process Mandarin Chinese aspect information, probably due to the complex feature of Mandarin Chinese aspect maker, the participants' L2 proficiency and age of L2 acquisition.

17.
Methods Mol Biol ; 2394: 485-498, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35094342

RESUMO

Mutations in protein kinases are often associated with the development of cancer, and application of mutant-specific inhibitors as therapeutic measures have shown a remarkable improvement in prolonging patient survival. However, it has also been observed that tumors bearing certain mutation types are more resistant to current approved drugs. Importantly, many resistant mutations are located in regions outside substrate or inhibitor binding sites, indicating allosteric effects. Understanding how mutations trigger effects over a distant site of the protein requires a deeper investigation of the molecular origin of allosteric regulation networks in kinases. In this chapter, we show the application of single-molecule optical tweezers to selectively manipulate specific regions of proteins to trace allosteric signals, thereby allowing the elucidation of allosteric communication networks. We illustrate this approach using as model system the regulatory subunit of protein kinase A. This single-molecule optical tweezers approach, however, can be readily applicable to study other kinases, and can be further expanded to screen potential allosteric drugs for future therapeutics.


Assuntos
Pinças Ópticas , Proteínas Quinases , Regulação Alostérica , Sítios de Ligação , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Quinases/metabolismo
18.
Front Psychol ; 13: 1071906, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36655024

RESUMO

In recent years, quantitative methods have been increasingly used in interlanguage studies, but these studies have mostly focused on the micro level with an emphasis on certain syntactic structures, rather than the macro where interlanguage is perceived as a whole. There remains a paucity of quantitative studies on interlanguage from the typological perspective. With the majority of the studies focused on the written interlanguage, there is also a lack of sufficient research on its spoken modality. Based on a syntactically annotated corpus and using the quantitative linguistic metric of dependency direction, we have investigated the typological changes in the Chinese interlanguage in both written and spoken modalities. The findings are as follows: (1) the typological features of interlanguage vary across modalities at both macro and micro levels; (2) dependency direction is proved to be an inappropriate indicator to measure the general typological characteristics of interlanguage development due to its failure to reflect the changes in the spoken modality; (3) both macro and micro perspectives taken into consideration, typological errors in the interlanguage is more likely to occur in the spoken modality than in the written one, in which learners may be restricted by greater time pressure and cognitive load in utterance. These factors may affect the distribution of dependency direction in the oral modality, and may be the reason why it is not appropriate to use dependency direction as a measure of changes in mediated language typological features in the oral modality. It is expected that our study will bring insight into second language research with more objective and holistic evidence.

19.
Brain Sci ; 11(9)2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34573255

RESUMO

This is a study of the collocation of Chinese verbs with different lexical aspects and aspect markers. Using event-related potentials (ERPs), we explored the processing of aspect violation sentences. In the experiment, we combined verbs of various lexical aspect types with the progressive aspect marker zhe, and the combination of the achievement verbs and the progressive aspect marker zhe constituted the sentence's aspect violation. The participants needed to judge whether a sentence was correct after it was presented. Finally, we observed and analyzed the components of ERPs. The results suggest that when the collocation of aspect markers and lexical aspect is ungrammatical, the N400-like and P600 are elicited on aspect markers, while the late AN is elicited by the word after the aspect marker. P600 and N400-like show that the collocation of Chinese verbs with various lexical aspects and aspect markers involve not only syntactic processing, but also the semantic processing; and the late AN may have been due to the syntax revision and the conclusion at the end of sentences.

20.
Front Psychol ; 12: 643120, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335361

RESUMO

Over time, interlanguage studies have shifted from early qualitative to quantitative studies of specific linguistic structures. However, the focus of these studies is usually on one aspect of an interlanguage instead of the whole system. The ideal object of interlanguage research is a second language (L2) learner language system, for only in this way can the entire L2 learning process can be examined. As a self-organizing and self-regulated system, the panorama of interlanguage can be revealed objectively through a complex network approach. In this study, we construct eight interlanguage dependency syntactic networks of varying proficiency levels and modalities, and conduct a quantitative study of respective network parameters. We find that all syntactic networks of Chinese L2 learners (English native speakers) initially present scale-free and small-world properties. Additionally, there is no sudden syntactic emergence in interlanguage with different modalities. This suggests varying regularities in the development of a syntactic network between interlanguage and native language acquisition. Moreover, the first language plays an important role in L2 development. The network parameters (), L, C, ND, and NC can differentiate interlanguage modalities, and five quantitative parameters, , C, ND, γ', and NC, can indicate L2 proficiency.

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