A Review on the Role of Token Frequency in the Acquisition of Argument Structures

The role of frequency in second language acquisition has become an important focus among second language acquisition researchers. Argument structure, as one of the core topics of verbs, has always been the focus of academic attention. Frequency has a certain influence on second language construction acquisition, and the corresponding research is abundant. This paper reviews the research on the acquisition of argument structure construction with token frequency and its enlightenment to teaching, and puts forward some suggestions for future research

Palladium nanosheets as highly stable and effective contrast agents for in vivo photoacoustic molecular imaging

电子邮件地址:[email protected],[email protected] stable and efficient contrast agent is highly desirable for photoacoustic (PA) imaging applications. Recently gold nanostructures have been widely reported and studied for PA imaging and photothermal therapy. However, the structures of the nonspherical gold nanoparticles are easily destroyed after laser irradiation and thus may fail to complete the intended tasks. In this study, we propose to apply palladium nanosheets (PNSs), with strong optical absorption in the near-infrared (NIR) region, as a new class of exogenous PA contrast agents. PA and ultrasound (US) images were acquired sequentially by a portable and fast photoacoustic tomography (PAT) system with a hand-held transducer. Significant and long-lasting imaging enhancement in SCC7 head and neck squamous cell carcinoma was successfully observed in mice by PAT over time after tail vein administration of PNSs. The morphology and functional perfusion of the tumors were delineated in PA images due to the nanoparticle accumulation. PAT of the main organs was also conducted ex vivo to trace the fate of PNSs, which was further validated by inductively coupled plasma atomic emission spectrometry (ICP-AES). No obvious toxic effect was observed by in vitro MTT assay and ex vivo histological examination 7 days after PNS administration. With the combination of a portable imaging instrument and signal specificity, PNSs might be applied as stable and effective agents for photoacoustic cancer detection, diagnosis and treatment guidance.National Science Foundation of China 81301257 81371596 National Basic Research Program of China (973 program) 2013CB733802 2014CB744503 intramural research program of the National Institute of Biomedical Imaging and Bioengineerin

Characteristics and potential biomarkers of flavor compounds in four Chinese indigenous chicken breeds

Chinese indigenous chickens have a long history of natural and artificial selection and are popular for their excellent meat quality and unique flavor. This study investigated six meat quality-related traits in Ningdu yellow, Baier yellow, Kangle, and Shengze 901 chickens. Two-dimensional gas chromatography-time-of-flight mass spectrometry was used to detect unique flavors in 24 breast muscle samples from the same phenotyped chickens. Overall, 685, 618, 502, and 487 volatile organic compounds were identified in Ningdu yellow, Baier yellow, Kangle, and Shengze 901 chickens, respectively. The flavor components were separated into eight categories, including hydrocarbons and aldehydes. Multivariate analyses of the identified flavor components revealed some outstanding features of these breeds. For example, the hydrocarbons (22.09%) and aldehydes (14.76%) were higher in Ningdu yellow chickens and the highest content of N, N-dimethyl-methylamine was in Ningdu yellow, Baier yellow, and Shengze 901 chickens, indicating the maximum attribution to the overall flavor (ROAV = 439.57, 289.21, and 422.80). Furthermore, we found that 27 flavor compounds differed significantly among the four Chinese breeds, including 20 (e.g., 1-octen-3-ol), two (e.g., 2-methyl-naphthalene), four (e.g., 2,6-lutidine), and one (benzophenone) flavor components were showed significant enrichment in Ningdu yellow, Baier yellow, Kangle, and Shengze 901 chickens, respectively. The flavor components enriched in each breed were key biomarkers distinguishing breeds and most were significantly correlated with meat quality trait phenotypes. These results provide novel insights into indigenous Chinese chicken meat flavors

Biosynthesized Ag/alpha-Al2O3 catalyst for ethylene epoxidation: the influence of silver precursors

NSFC [21206140, 21036004]; State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals [SKL-SPM-201210]Biosynthesized Ag/alpha-Al2O3 catalysts toward ethylene epoxidation were prepared with Cinnamomum camphoratrees (CC) extract using AgNO3, silver-ammonia complex ([Ag (NH3)(2)](+)) and silver-ethylenediamine complex ([Ag(en)(2)](+)) as the silver precursors. The catalyst from [Ag(en)(2)](+) demonstrated better activity compared to the catalysts from the other two precursors, 1.41% EO concentration with EO selectivity of 79.1% and 12.0% ethylene conversion were achieved at 250 degrees C. To investigate the influence of silver precursors on the catalytic performance, three catalysts were characterized by XRD, UV-Vis, XPS, SEM and O-2-TPD techniques. The results indicated that [Ag(en)(2)](+) precursors could be reduced more effectively by CC extract, and Ag particles were successfully immobilized onto the alpha-Al2O3 support under mild conditions. Moreover, a silver defects surface on the Ag/alpha-Al2O3 catalyst from [Ag(en)(2)](+) precursors had the best oxygen activation ability, playing an important role in the generation of electrophilic oxygen species which were responsible for the epoxidation reaction of C=C to EO

Biosynthesized Ag/α-Al2O3 catalyst for ethylene epoxidation: The influence of silver precursors

Biosynthesized Ag/α-Al2O3 catalysts toward ethylene epoxidation were prepared with Cinnamomum camphoratrees (CC) extract using AgNO3, silver-ammonia complex ([Ag (NH3) 2]+) and silver-ethylenediamine complex ([Ag(en) 2]+) as the silver precursors. The catalyst from [Ag(en)2]+ demonstrated better activity compared to the catalysts from the other two precursors, 1.41% EO concentration with EO selectivity of 79.1% and 12.0% ethylene conversion were achieved at 250 °C. To investigate the influence of silver precursors on the catalytic performance, three catalysts were characterized by XRD, UV-Vis, XPS, SEM and O 2-TPD techniques. The results indicated that [Ag(en) 2]+ precursors could be reduced more effectively by CC extract, and Ag particles were successfully immobilized onto the α-Al 2O3 support under mild conditions. Moreover, a silver defects surface on the Ag/α-Al2O3 catalyst from [Ag(en)2]+ precursors had the best oxygen activation ability, playing an important role in the generation of electrophilic oxygen species which were responsible for the epoxidation reaction of CC to EO. ? 2014 the Partner Organisations

New perspectives on microbiome and nutrient sequestration in soil aggregates during long-term grazing exclusion

15 páginas.- 5 figuras.- referencias.-Grazing exclusion alters grassland soil aggregation, microbiome composition, and biogeochemical processes. However, the long-term effects of grazing exclusion on the microbial communities and nutrient dynamics within soil aggregates remain unclear. We conducted a 36-year exclusion experiment to investigate how grazing exclusion affects the soil microbial community and the associated soil functions within soil aggregates in a semiarid grassland. Long-term (36 years) grazing exclusion induced a shift in microbial communities, especially in the 2 mm aggregates, and reduced carbon (C) sequestration potential thus revealing a negative impact of long-term GE. In contrast, 11–26 years of grazing exclusion greatly increased C sequestration and promoted nutrient cycling in soil aggregates and associated microbial functional genes. Moreover, the environmental characteristics of microhabitats (e.g., soil pH) altered the soil microbiome and strongly contributed to C sequestration. Our findings reveal new evidence from soil microbiology for optimizing grazing exclusion duration to maintain multiple belowground ecosystem functions, providing promising suggestions for climate-smart and resource-efficient grasslands.This work was financially supported by the National Natural Science Foundation of China (32061123007, 41977031), the Strategic Priority Research Program of Chinese Academy of Sciences (XDB40020202), and the Natural Science Foundation of Hubei Province, China (2020CFA013). Manuel Delgado-Baquerizo acknowledges support from the Spanish Ministry of Science and Innovation for the I+D+i project PID2020-115813RA-I00 and TED2021-130908B-C41 funded by MCIN/AEI/10.13039/501100011033.Peer reviewe