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1.
方平 《学海》2007,(2):107-113
清朝末年,随着报刊业的发展和社会思潮的流转,报人对报刊的社会角色和功用提出了自己的理解,始曰“耳目”、“喉舌”,继之言“第四种族”与“舆论之母”,再则称“政监”与“向导”,愈转愈进,愈转愈激。由于立意于作为“政监”和“向导”,报刊特重“主观”之“言论”,遂由“代言”而逐渐转向“灌输”,甚至直接“制造舆论”。因此,尽管报人与报刊仍以代表“公意”、“公益”而自期,但主观之“言论”究竟在多大程度表达了“一般国民之公共意志”而于“民主政治”建设有所贡献,不免令人生疑。  相似文献   
2.
大鼠作业成绩与脑内亮氨酸脑啡肽含量变化的相关性研究   总被引:1,自引:0,他引:1  
本工作采用穿梭式电击回避反应法和脑啡肽的放射免疫测定法,分析比较了大鼠作业成绩与脑内壳氨酸脑啡肽(Leu-enkephalin,LEK)含量的关系,在本实验条件下,观察到作业成绩不良组纹状体内LEK含量显著高于成绩优良组和对照组,并由实验证明,它们之间的差异不是由于在实验中接受电击的次数或电击总量不同造成的。这一结果提示,内源性亮氨酸脑啡肽可能参与记忆获得的调制。  相似文献   
3.
Children and their families have been significantly impacted by the unfolding of the COVID-19 syndemic. We sought to identify (1) groups of families with distinct profiles of joint trajectories of parental anxiety and child emotional distress and (2) protective and risk factors associated with these dual-trajectory profiles. A sample of 488 parents (65% White; 77% mothers) with 3- to 8-year-old children (MAge = 5.04, SDAge = 1.59) was followed from late March to early July in 2020. Survey data on parent (i.e., anxiety symptoms) and child (i.e., emotional distress) adjustment were collected at three time points. Using multivariate growth mixture modeling, we identified one group with low parental anxiety and child emotional distress (42.7%) and three other distinct groups with varying risk levels among parents and/or children. We also identified protective (e.g., positive parenting) and risk (e.g., child negative affect, negative parenting, perceived stress with racism) factors in predicting parent and child adjustment. It can be concluded that, overall, our sample (mostly middle- and high-socioeconomic status families) demonstrated family resilience amid COVID-19, consistent with prior disaster coping literature. At the same time, our findings also indicated the need to identify at-risk families and modifiable factors for post-disaster public health interventions.  相似文献   
4.
注意缺陷多动障碍(attentiondeficit/hyperactivitydisorder,ADHD)行为控制不足与决策冲动密切相关,后者受内侧前额皮层(medial prefrontal cortex, mPFC)与伏隔核(nucleus accumbens, NAc)调节。为调查ADHD决策冲动与m PFC-NAc间功能耦合的关系,研究采用ADHD模型SHR (spontaneously hypertensive rat, SHR)大鼠,结合延迟折扣任务和在体电生理,研究发现,与对照Wistar (WIS)大鼠相比, SHR大鼠对延迟大奖赏的选择百分比降低; WIS大鼠m PFC-NAc的Theta频段相干值表现为延迟选择时显著大于立即选择时、首次选择时大于连续选择时、转换试次时大于连续试次时,而SHR大鼠在上述条件均低于WIS大鼠。回归分析发现m PFC-NAc的相干差值与延迟大奖赏选择率显著正相关。结果表明m PFC-NAc间功能联系减弱是ADHD决策冲动缺陷的重要环路基础,该缺陷与其深度信息加工以及策略转换能力受损有关,扩展了ADHD决策冲动的认知和神经机制的认识。  相似文献   
5.
Three experiments with 60 native Chinese speakers were conducted to examine the temporal structure of spoken sentence comprehension in Chinese. In the two sentence-gating experiments, listeners heard sentence fragments of various sizes, either successively or individually, and decided on the agent role of the sentence. In the agent-naming experiment, listeners repeated aloud the sentence agent upon hearing the sentence. Converging evidence was derived from these experiments indicating the usefulness of sentence gating in tapping into the temporal structure of comprehension and in evaluating listeners’ comprehension on the basis of partial information. Results from these experiments show that partial sentence information plays a very important role in Chinese sentence comprehension, and that Chinese listeners integrate incomplete and ungrammatical sentence fragments by reference to complete and grammatical models in the language. It is argued that these processing characteristics reflect properties of the Chinese language in which few morphological, grammatical, and syntactic constraints are placed on the relationships between sentence constituents.  相似文献   
6.
情绪活动和某些生理机能或心理过程的关系很久以来就已进行过大量的研究。外科手术前患者的情绪状态及其相应的生理机能的变化,也曾受到注意。患者在意识清醒状态下进行针麻手术,他的情绪状态对针麻过程及其效果的作用如何,这种情绪状态和某些心理、生理机能有什么联系?这是针麻临床上和理论上应予探讨的问题之一。本工作试图综合分析患者的情绪状态和与之伴随的某些生理生化指标变化,以探讨  相似文献   
7.
Computerized classification testing (CCT) aims to classify persons into one of two or more possible categories to make decisions such as mastery/non-mastery or meet most/meet all/exceed. A defining feature of CCT is its stopping criterion: the test terminates when there is enough confidence to make a decision. There is abundant research on CCT with a single cut-off, and two common stopping criteria are the sequential probability ratio test (SPRT) statistic and the generalized likelihood ratio statistic (GLR). However, there is a relative scarcity of research extending the SPRT to the multi-hypothesis case for when there is more than one cut-off. In this paper, we propose a new multi-category GLR (mGLR) statistic as well as a stochastically curtailed version of the CCT with three or more categories. A simulation study was conducted to show that the mGLR statistic outperformed the existing stopping rules by generating shorter average test length without sacrificing classification accuracy. Results also revealed that the stochastically curtailed mGLR successfully increased test efficiency in certain testing conditions.  相似文献   
8.
Chen  Ping  Wang  Chun 《Psychometrika》2021,86(1):299-326
Psychometrika - This study revisits the parameter estimation issues in multidimensional item response theory more thoroughly and investigates some computation details that have seldom been...  相似文献   
9.
为明确述情障碍与中学生人际关系间关系的内在机制,采用中学生人际关系量表、多伦多述情障碍量表、社交焦虑量表及领悟社会支持量表调查了北京市、石家庄市、佳木斯市三所中学7至11年级共998名学生,根据述情障碍的筛查标准,最终获得218份有效数据。结论如下:(1)述情障碍与社交焦虑呈显著正相关,与人际关系、社会支持呈显著负相关;人际关系与社交焦虑呈显著负相关,而与社会支持呈显著正相关;社交焦虑与社会支持呈显著负相关;(2)社交焦虑在述情障碍与中学生人际关系间起中介作用;社会支持在述情障碍与中学生人际关系间起调节作用;(3)"述情障碍→社交焦虑→中学生人际关系"这一中介路径的前半段,受到社会支持的调节。与高社会支持个体相比,述情障碍对低社会支持个体的社交焦虑影响更大。  相似文献   
10.
为探讨父母学业参与和学业压力与青少年早期学业投入之间的关系,考察成就目标取向的中介作用,以及学业成就水平在该中介过程中的调节作用,对2487名初一学生进行测查,结果发现:(1)父母学业参与正向预测青少年早期个体的学业投入、负向预测学业抽离,父母学业压力正向预测学业抽离;(2)掌握目标取向在父母学业参与和青少年早期的学业投入之间起正向中介作用,在父母学业参与和学业抽离间发挥负向中介作用;表现回避目标取向在父母学业压力和学业抽离间具有正向中介作用;(3)掌握目标取向的中介作用受到学业成就水平的调节。研究结果揭示了父母学业参与和学业压力对青少年早期的学业投入的共同作用,为从家庭层面提高青少年的学业投入水平提供了参考。  相似文献   
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