149 elementary school pupils were selected as the subjects for this study, to whom five tracking assessments of their verbal vocabulary knowledge were given over a period of three years. In addition, a latent variable...149 elementary school pupils were selected as the subjects for this study, to whom five tracking assessments of their verbal vocabulary knowledge were given over a period of three years. In addition, a latent variable growth model was adopted to explore grades 1-3 elementary school pupil's developmental trajectory for verbal Chinese vocabulary knowledge. The phonological awareness, homomorphic morpheme awareness, compound morpheme awareness and family socioeconomic status(SES) on the students' verbal vocabulary knowledge were also investigated. The ndings are: 1, grades 1-3 elementary school pupils verbal Chinese vocabulary knowledge developmental trajectory shows a curvilinear form, of which linear development is trended in the first two years, and as of the third year the developmental rate doubles the previous two years, whereas individual di erences are remarkable in both the initial level and the growth rate; 2, awareness of phonetics, homomorphic morphemes and complex morphemes as well as the family socioeconomic status can be referred to for a positive forecast of the students' initial level of verbal vocabulary knowledge; 3, only the awareness of homomorphic morphemes and the family socioeconomic status can be applied to a positive prediction of the students' verbal vocabulary knowledge growth rate..展开更多
Latent fingerprints(LFPs)at the crime scene are served as important clues to locate the trajectory of criminal behavior and portray the characteristics of the suspect.Therefore,visualizing LFPs is of considerable sign...Latent fingerprints(LFPs)at the crime scene are served as important clues to locate the trajectory of criminal behavior and portray the characteristics of the suspect.Therefore,visualizing LFPs is of considerable significance.In this work,the europium metal-organic framework(Eu-MOF)sensor was successfully constructed for sensitive detection of gallic acid(3,4,5-trihydroxybenzoic acid,GA)and visualization of the sweat LFPs.The boric-acid-modified Eu-MOF was prepared by using the simple one-pot solvothermal method using Eu as the metal i ion center and 3,5-dicarboxybenzeneboronic acid(BBDC)as the organic ligand.The sensor showed desirable photoluminescent performance through the chelating of BBDC with Eu3+.The sensor exhibited the satisfactory linear relationship to GA in the range of 1 nM to 20 nM with a low detection limit of 0.34 nM under the optimized conditions.The prepared sensor with ideal selectivity to GA was successfully applied for visualizing LFPs on porous substrates with the high contrast and superior stability.Given the good performance of the sensor,all fingerprint images obtained from 1200 samples presented clear friction ridges and met the identification criteria.Notably,the sensor had less impact on the subsequent deoxyribonucleic acid(DNA)detection,displaying a promising perspective for applications in extracting physical evidence of site investigation.展开更多
基金project No.17NDJC120YB of philosophy and social sciences under the planning of Zhejiang provincea Youth Fund research project No.16YJC190002 of humanities and social sciences under the planning of the Ministry of Educationa key research project No.13&ZD188 of the of the National Social Science Fund of China
文摘149 elementary school pupils were selected as the subjects for this study, to whom five tracking assessments of their verbal vocabulary knowledge were given over a period of three years. In addition, a latent variable growth model was adopted to explore grades 1-3 elementary school pupil's developmental trajectory for verbal Chinese vocabulary knowledge. The phonological awareness, homomorphic morpheme awareness, compound morpheme awareness and family socioeconomic status(SES) on the students' verbal vocabulary knowledge were also investigated. The ndings are: 1, grades 1-3 elementary school pupils verbal Chinese vocabulary knowledge developmental trajectory shows a curvilinear form, of which linear development is trended in the first two years, and as of the third year the developmental rate doubles the previous two years, whereas individual di erences are remarkable in both the initial level and the growth rate; 2, awareness of phonetics, homomorphic morphemes and complex morphemes as well as the family socioeconomic status can be referred to for a positive forecast of the students' initial level of verbal vocabulary knowledge; 3, only the awareness of homomorphic morphemes and the family socioeconomic status can be applied to a positive prediction of the students' verbal vocabulary knowledge growth rate..
基金The work was supported by the People's Public Security University of China Double Class Innovative Research Special Project on Criminal Science and Technology(Grant No.2023SYL06).
文摘Latent fingerprints(LFPs)at the crime scene are served as important clues to locate the trajectory of criminal behavior and portray the characteristics of the suspect.Therefore,visualizing LFPs is of considerable significance.In this work,the europium metal-organic framework(Eu-MOF)sensor was successfully constructed for sensitive detection of gallic acid(3,4,5-trihydroxybenzoic acid,GA)and visualization of the sweat LFPs.The boric-acid-modified Eu-MOF was prepared by using the simple one-pot solvothermal method using Eu as the metal i ion center and 3,5-dicarboxybenzeneboronic acid(BBDC)as the organic ligand.The sensor showed desirable photoluminescent performance through the chelating of BBDC with Eu3+.The sensor exhibited the satisfactory linear relationship to GA in the range of 1 nM to 20 nM with a low detection limit of 0.34 nM under the optimized conditions.The prepared sensor with ideal selectivity to GA was successfully applied for visualizing LFPs on porous substrates with the high contrast and superior stability.Given the good performance of the sensor,all fingerprint images obtained from 1200 samples presented clear friction ridges and met the identification criteria.Notably,the sensor had less impact on the subsequent deoxyribonucleic acid(DNA)detection,displaying a promising perspective for applications in extracting physical evidence of site investigation.
