Nonlinear Predictive Models for Multiple Mediation Analysis: With an Application to Explore Ethnic Disparities in Anxiety and Depression Among Cancer Survivors

Mediation analysis allows the examination of effects of a third variable (mediator/confounder) in the causal pathway between an exposure and an outcome. The general multiple mediation analysis method (MMA), proposed by Yu et al., improves traditional methods (e.g., estimation of natural and controlled direct effects) to enable consideration of multiple mediators/confounders simultaneously and the use of linear and nonlinear predictive models for estimating mediation/confounding effects. Previous studies find that compared with non-Hispanic cancer survivors, Hispanic survivors are more likely to endure anxiety and depression after cancer diagnoses. In this paper, we applied MMA on MY-Health study to identify mediators/confounders and quantify the indirect effect of each identified mediator/confounder in explaining ethnic disparities in anxiety and depression among cancer survivors who enrolled in the study. We considered a number of socio-demographic variables, tumor characteristics, and treatment factors as potential mediators/confounders and found that most of the ethnic differences in anxiety or depression between Hispanic and non-Hispanic white cancer survivors were explained by younger diagnosis age, lower education level, lower proportions of employment, less likely of being born in the USA, less insurance, and less social support among Hispanic patients.     

Outliers and Influential Observations in Exponential Random Graph Models

We discuss measuring and detecting influential observations and outliers in the context of exponential family random graph (ERG) models for social networks. We focus on the level of the nodes of the network and consider those nodes whose removal would result in changes to the model as extreme or “central” with respect to the structural features that “matter”. We construe removal in terms of two case-deletion strategies: the tie-variables of an actor are assumed to be unobserved, or the node is removed resulting in the induced subgraph. We define the difference in inferred model resulting from case deletion from the perspective of information theory and difference in estimates, in both the natural and mean-value parameterisation, representing varying degrees of approximation. We arrive at several measures of influence and propose the use of two that do not require refitting of the model and lend themselves to routine application in the ERGM fitting procedure. MCMC p values are obtained for testing how extreme each node is with respect to the network structure. The influence measures are applied to two well-known data sets to illustrate the information they provide. From a network perspective, the proposed statistics offer an indication of which actors are most distinctive in the network structure, in terms of not abiding by the structural norms present across other actors.     

<Emphasis Type="Italic">Wh</Emphasis>-Questions,Universal Statements and Free Choice Inferences in Child Mandarin

This study investigated 5-year-old Mandarin-speaking children’s comprehension of wh-questions, universal statements and free choice inferences. Previous research has found that Mandarin-speaking children assign a universal interpretation to sentences with a wh-word (e.g., shei ‘who’) followed by the adverbial quantifier dou ‘all’ (Zhou in Appl Psycholinguist 36:411–435, 2013). Children also compute free choice inferences in sentences that contain a modal verb in addition to a wh-word and dou (Zhou, in: Nakayama, Su, Huang (eds.) Studies in Chinese and Japanese language acquisition: in honour of Stephen Crain. John Benjamins Publishing Company, Amsterdam, pp 223–235, 2017). The present study used a Question-Statement Task to assess children’s interpretation of sentences containing shei + dou, both with and without the modal verb beiyunxu ‘was allowed to’, as well as the contrast between sentences with shei + dou, which are statements for adults, versus ones with dou + shei, which are wh-questions for adults. The 5-year-old Mandarin-speaking child participants exhibited adult-like linguistic knowledge of the semantics and pragmatics of wh-words, the adverbial quantifier dou, and the deontic modal verb beiyunxu.     

Differences in Scope Assignments for Child and Adult Speakers of Mandarin

The present study used a Truth Value Judgment Task to investigate whether changes in sentence structure lead to corresponding changes in the assignment of scope relations by Mandarin-speaking children and adults. In one condition, participants were presented with ordinary negative sentences containing disjunction; this condition was designed to verify the existing claim that disjunction is a positive polarity item for adult speakers of Mandarin, but not for child speakers. In a second condition, participants were presented with negative sentences where the disjunction phrase was preposed from object position; this condition was designed to examine the extent to which changes in sentence structure can result in changes in scope assignments to negated disjunctions. The results indicate that the preposed disjunction phrase undergoes reconstruction for children, whereas reconstruction is blocked for adults. This finding also suggests that Mandarin-speaking children and adults exhibit different scope preferences for negated disjunctions, regardless of where the disjunction phrase appears in the surface syntax.     

How Possessive Relations are Mapped onto Child Language: A View from Mandarin Chinese

The present studies sought to investigate the mapping relations between language and cognition by focusing on how Mandarin-speaking children acquire the mapping between their conceptual knowledge of possession and their linguistic expressions of possession. Two experiments were conducted. Experiment 1 used a comprehension task to explore whether young children are able to map their knowledge of possessive constructions onto their interpretation of possessive relations. Experiment 2 employed a production task to examine whether they are able to map their knowledge of possessive relations onto their linguistic expressions of possession. The findings were that 4-year-olds exhibited correct comprehension and production of possessive DE constructions, indicating that by age 4, Mandarin-speaking children have already established the mapping between their conceptual knowledge of possession and their linguistic expressions of possession. By contrast, 3-year-olds exhibited response patterns that suggest a developmental stage where they use noun–noun compounds to represent possessive relations before they map possessive relations onto possessive constructions.     

Motivated attention to fear-related stimuli: Evidence for the enhanced processing of fear in the late positive potential

Differences in the processing of emotions like fear and sadness have important implications for our understanding of many psychological phenomena (e.g., attentional biases, psychopathology). The late positive potential (LPP) is an established event-related potential that reflects motivated attention to emotional stimuli at the neural level with excellent temporal resolution, but has been infrequently used to study differences across emotions. Drawing on functional theories of emotion suggesting that the quick processing of fear-inducing stimuli increases chances of survival, we hypothesized that fear-inducing pictures would produce larger LPP amplitudes compared to other emotions (happy and sad) in the early time windows of the LPP (e.g., 400–700, 700–1000 ms). The results supported our hypothesis, offering new, albeit preliminary, evidence of the differential processing of threat-related stimuli on the LPP.     

抑郁在青少年核心自我评价与自杀意念间的中介作用:基于Bootstrap法和MCMC法的实证研究

考察抑郁在青少年核心自我评价与自杀意念间的中介作用。对502名高中生进行量表测评。通过偏差校正的Bootstrap法和有先验信息的MCMC法求出中介效应值的95%置信区间分别为[-.030,-.011]和[-.024,-.014],提示抑郁的中介效应显著。效应量k2、R2med分别为.124、.104,偏差校正的Bootstrap法抽样5000次后,构建的效应量的95%置信区间分别为[.070,.178]、[.063,.156],两种指标共同验证效应量为中等。研究结果说明抑郁在核心自我评价与自杀意念间起部分中介作用,效应量中等。     

反应抑制的训练:内容、效果与机制

近期的研究发现,个体的反应抑制能力具有一定的可塑性。研究者多采用双盲随机对照实验设计,训练的对象包括儿童、成人和特殊群体,研究者通过Go/Nogo、Stop-signal等任务进行为期1周至3周,45至7200试次不等的抑制控制能力训练,并结合行为、脑电以及脑成像等技术对训练效果进行评估,研究结果发现,接受了抑制控制训练的个体其抑制能力得到提升,并伴随脑神经活动的变化。另外,研究者发现,抑制控制能力的训练效果还可以迁移至个体日常生活中的表现。但是,也有些研究并未发现抑制控制训练的效果。训练任务的设置,评估任务的选择以及被试反应策略的差异等因素可能会影响训练的效果。抑制控制训练引发行为与大脑活动的变化可能是由于训练导致了个体建立了自上而下有意识的抑制控制模式和自下而上的自动抑制模式。反应抑制和冲突抑制可塑性的比较,儿童与老年人抑制功能的训练以及训练效果的追踪研究将成为该领域日后研究的重点问题。     

Counterfactual comparison modulates fairness consideration in the mini‐ultimatum game: An event‐related potentials study

Existing literature on the mini‐ultimatum game indicates that counterfactual comparison between chosen and unchosen alternatives is of great importance for individual's fairness consideration. However, it is still unclear how counterfactual comparison influences the electrophysiological responses to unfair chosen offers. In conjunction with event‐related potentials’ (ERPs) technique, the current study aimed to explore the issue by employing a modified version of the mini‐ultimatum game where a fixed set of two alternatives (unfair offer vs. fair alternative, unfair vs. hyperfair alternative, unfair offer vs. hyperunfair alternative) was presented before the chosen offer. The behavioral results showed that participants were more likely to accept unfair chosen offers when the unchosen alternative was hyperunfair than when the unchosen alternative was fair or hyperfair. The ERPs results showed that the feedback‐related negativity (FRN) elicited by unfair chosen offers was insensitive to the type of unchosen alternative when correcting for possible overlap with other components. In contrast, unfair chosen offers elicited larger P300 amplitudes when the unchosen alternative was hyperunfair than when the unchosen alternative was fair or hyperfair. These findings suggest that counterfactual comparison may take effect at later stages of fairness consideration as reflected by the P300.     

Atomic imaging of the interface between M23C6-type carbide and matrix in a long-term ageing polycrystalline Ni-based superalloy

Besides the well-known cube-on-cube orientation relationship (OR) between M₂₃C₆ carbide and matrix, we have determined a new OR named as the twin-related OR in a long-term ageing Ni-based superalloy on the basis of the extensive and detailed electron diffraction analyses. Furthermore, by means of atomic-resolution high angle annular dark-field imaging technique which is implemented in the aberration-corrected scanning transmission electron microscope, we elucidated the interfacial characteristics between M₂₃C₆ and matrix for above two types of ORs. Taking into account of the interfacial characteristics, we propose that the twin-related OR possesses a higher total interfacial energy. Thus, its frequency of occurrence is lower than that of the cube-on-cube OR though both ORs are usually seen in the long-term ageing samples.