Models of child–parent attachment in attention deficit hyperactivity disorder: Links to executive functions

This study explored multiple attachment relationships and examined four conceptual models of child–mother/father attachment—monotropy, hierarchy, independence, integration—to explain executive functioning (EF) in attention deficit hyperactivity disorder (ADHD) versus typical development (TD; n = 50 each; age: M = 11.45, SD = .50). Significant ADHD versus TD differences emerged on all EF measures and on distribution into four clusters (secure attachment to both parents, neither parent, only father, only mother). For both groups, results supported two attachment models: (a) monotropy: child–mother attachment predicted all EF measures; child–father attachment predicted none and (b) integration: clusters differed significantly on all EF measures. Children with ADHD comprised ～74% of the high‐risk cluster (concordant insecure attachment, highest EF difficulties). Discussion focused on unique risk/protective roles played by each parental attachment for understanding EF in children with ADHD or TD.     

A Model‐Based Cluster Analysis of Maternal Emotion Regulation and Relations to Parenting Behavior

In a diverse community sample of mothers (N = 108) and their preschool‐aged children (M_age = 3.50 years), this study conducted person‐oriented analyses of maternal emotion regulation (ER) based on a multimethod assessment incorporating physiological, observational, and self‐report indicators. A model‐based cluster analysis was applied to five indicators of maternal ER: maternal self‐report, observed negative affect in a parent–child interaction, baseline respiratory sinus arrhythmia (RSA), and RSA suppression across two laboratory tasks. Model‐based cluster analyses revealed four maternal ER profiles, including a group of mothers with average ER functioning, characterized by socioeconomic advantage and more positive parenting behavior. A dysregulated cluster demonstrated the greatest challenges with parenting and dyadic interactions. Two clusters of intermediate dysregulation were also identified. Implications for assessment and applications to parenting interventions are discussed.     

Effect of Al-Zr clusters on the thermal stability of Cu-Zr-rich Cu-Zr-Al bulk metallic glasses

The Gibbs free energy of formation, ?G^a, of the amorphous phase of Cu–Zr-rich Cu–Zr–Al bulk metallic glasses (BMGs) has been calculated over a broad composition region to re-evaluate their thermal stability, based on the efficient cluster packing model. It is found that Al–Zr clusters have an important effect on the thermal stability of the Cu–Zr–Al BMGs with the same Cu/Zr content ratio. The crystallisation of the BMGs involves crystallisation of both Al–Zr and Cu–Zr clusters. The results could be useful for predicting the thermal stability and understanding the underlying mechanism of crystallisation of multicomponent metallic glasses.     

Determination of parent β-phase orientation from inherited orthorhombic phase in β → O + B2 phase transformation of Ti–22Al–25Nb alloy

We propose and describe a method for determining the orientation of parent body-centred cubic (bcc) β grains at high temperatures from the orientations of the orthorhombic variants observed at room temperature as applied to the case of high-Nb-containing Ti₃Al-based alloys. The method is based on knowledge of the orientation relationship between the parent and inherited phase. By averaging, the procedure enables determination of the most probable parent orientation using an approximate orientation relationship. The β?→?O transformation in Ti₃Al-based Ti–22Al–25Nb alloy is very suitable for checking the relevance and effectiveness of the method because, in this case, after certain processing, some β-phase is retained at room temperature.     

Optimal Partitioning of a Data Set Based on the p-Median Model

Although the K-means algorithm for minimizing the within-cluster sums of squared deviations from cluster centroids is perhaps the most common method for applied cluster analyses, a variety of other criteria are available. The p-median model is an especially well-studied clustering problem that requires the selection of p objects to serve as cluster centers. The objective is to choose the cluster centers such that the sum of the Euclidean distances (or some other dissimilarity measure) of objects assigned to each center is minimized. Using 12 data sets from the literature, we demonstrate that a three-stage procedure consisting of a greedy heuristic, Lagrangian relaxation, and a branch-and-bound algorithm can produce globally optimal solutions for p-median problems of nontrivial size (several hundred objects, five or more variables, and up to 10 clusters). We also report the results of an application of the p-median model to an empirical data set from the telecommunications industry.     

Constrained k‐means on cluster proportion and distances among clusters for longitudinal data analysis

Clustering individuals by measures of similarity or dissimilarity at trajectories of changes in longitudinal data enables determination of typical patterns of development and growth. The present research proposes a new constrained k‐means method with lower bound constraints on cluster proportions and distances among clusters at focused variables and time points to fulfill various needs in clustering longitudinal data. The method assumes a large number of clusters at the onset and iteratively deletes and combines clusters according to these constraints. An additional property of the proposed constrained k‐means includes direct estimation of the unknown number of clusters. Simulation results clearly show the usefulness of the method for extracting clusters in plausible, real‐life analysis including non‐normality within clusters, and the proposed algorithm works well and convergence of the estimates is satisfactory. An actual example using Japanese longitudinal data regarding sleep habits and mental health is presented to verify the utility of the proposed constrained k‐means.     

The Role of Parents in Emerging Adults’ Psychological Well‐Being: A Person‐Oriented Approach

The purpose of this study was to gain an overview of Spanish emerging adults’ family relationships and their link with psychological well‐being and psychological distress. The sample comprised 1502 undergraduate students (903 women and 599 men) aged between 18 and 29 (M = 20.32 and SD = 2.13), recruited from two universities in Spain. A cluster analysis identified three groups of families based on the centrality of five family variables: parental involvement, parental support for autonomy, parental warmth, behavioral control, and psychological control. The three groups or clusters were labeled high‐quality family relationships (HQ), intermediate‐quality family relationships (IQ), and low‐quality family relationships (LQ). Women were overrepresented in the HQ cluster, whereas men were overrepresented in the IQ cluster. Moreover, emerging adults who perceived better family relationships (high levels of parental involvement, parental support for autonomy and parental warmth, and low levels of behavioral and psychological control) were found to have a higher level of psychological adjustment. Thus, our results indicate that family plays a key role in the psychological well‐being of emerging adults. The discussion focuses on the implications of this finding for the parent‐child relationship, and explores how it extends our knowledge about family relationships during emerging adulthood.     

Posttraumatic Stress Disorder Symptom Clusters and Acquired Capability for Suicide: A Reexamination Using DSM-5 Criteria

This study used the interpersonal–psychological theory of suicide to explore the relationships among DSM-5 posttraumatic stress disorder (PTSD) symptom clusters derived from the six-factor anhedonia model and facets of acquired capability for suicide (ACS). In a sample of 373 trauma-exposed undergraduates, most PTSD symptom clusters were negatively associated with facets of ACS in bivariate correlations, but the anhedonia cluster was positively associated with ACS in regression models. Structure coefficients and commonality analysis indicated that anhedonia served as a suppressor variable for the other symptom clusters. Our findings further elucidate the complex relationship between specific PTSD symptom clusters and ACS.     

Parent Education for Migrant Mothers of Left‐Behind Children in China: A Pilot Randomized Controlled Trial

Although numerous studies have indicated the significance of parental support and parent–child communication in alleviating the adverse effects of parental departure on left‐behind children, researchers have rarely addressed the impact of parent education on migrant parents. On the basis of the results of a pilot randomized controlled trial, the study reported here involved examining the possible outcomes and feasibility of a parent education program for rural‐to‐urban migrant mothers of left‐behind children in China. Informed by an existential–narrative approach to parent education, the program was composed of six 2.5‐hour sessions. The sample included 56 migrant mothers recruited from a social service center in Shenzhen, China, who were randomly assigned to either the immediate group (n = 28, M = 34.82 years, SD = 4.12, aged 23–43) or the waitlist control group (n = 28, M = 34.68 years, SD = 4.53, aged 28–43). The hypotheses of the trial were twofold: that the program would positively affect participants’ parental identity and that it would improve mother–child relationships and parenting practices. The results revealed no significant difference in parental identity between the intervention group and the waitlist control group at the post‐test assessment after ruling out the effects of pretest survey scores. However, significant differences did emerge in parent–child relationships and parenting practices. Overall, the results corroborate the feasibility of examining the current program for migrant mothers in China in a full trial. The findings also offer insights into developing empirically supported parent education programs for migrant parents.     

Profiles and Correlates of Children’s Self-Reported Coping Strategies Using a Cluster Analytic Approach

We used cluster analysis to identify children’s coping profiles and to examine self- and parent-reported correlates of coping in a community sample. Participants included 135 children (M age = 11.27, s.d. = .59) recruited from local public elementary and junior high schools and 116 of their parents. Analyses included hierarchical cluster analysis (Ward’s method), followed by non-hierarchical (k-means) cluster analysis to confirm the cluster solution. Results yielded four clusters reflecting high, active, low, and indiscriminant patterns of coping strategies. Members of the active coping group self-reported the fewest symptoms of distress and the greatest number of prosocial competencies after controlling for social desirability. No differences emerged for parent-reported psychosocial functioning across coping profiles. Our results suggest that a combination of active coping strategies may be associated with better psychosocial functioning than a combination of active and avoidant coping strategies.     

Understanding the impact of attachment insecurity on PTSD symptoms among male Veterans and military personnel

ABSTRACT

Attachment insecurity (i.e., attachment anxiety and attachment avoidance) has been found to contribute to PTSD symptom severity in Veterans. However, little is known of the unique contribution of attachment insecurity on individual PTSD symptom clusters. In a community sample of 106 combat-deployed Veterans, active duty service members, and reservists, this study examined: (1) the relationships between childhood family experience, combat experience, attachment insecurity, and PTSD symptom clusters, and (2) the influence of attachment insecurity on PTSD symptom clusters. Results revealed significant correlations between attachment anxiety and all PTSD symptom clusters (rs = .22 –.43) and attachment avoidance and PTSD symptom clusters, except the avoidance cluster (rs = .21 ?.36). Four multiple regression analyses were employed to address the second study aim. Childhood family experiences predicted negative alterations in cognitions and mood (β = –.30) and alterations in arousal and reactivity (β = –.20). Further, combat experience significantly predicted each symptom cluster of PTSD (βs = .03 –.44). In the second step, attachment anxiety and attachment avoidance were added to each model. Attachment anxiety and attachment avoidance predicted negative alterations in cognitions and mood (βs = .22 and .35) and alterations in arousal and reactivity (βs = .27 and .17). Inconsistent with previous research, attachment insecurity did not predict symptoms of avoidance. These results highlight the impact of attachment among a diverse sample of trauma exposed individuals and may provide insights for clinical implications and therapeutic approaches when working with Veterans and military personnel high in attachment insecurity.     

Multilevel mediation analysis: The effects of omitted variables in the 1–1–1 model

Multilevel mediation analysis examines the indirect effect of an independent variable on an outcome achieved by targeting and changing an intervening variable in clustered data. We study analytically and through simulation the effects of an omitted variable at level 2 on a 1–1–1 mediation model for a randomized experiment conducted within clusters in which the treatment, mediator, and outcome are all measured at level 1. When the residuals in the equations for the mediator and the outcome variables are fully orthogonal, the two methods of calculating the indirect effect (ab, c – c′) are equivalent at the between‐ and within‐cluster levels. Omitting a variable at level 2 changes the interpretation of the indirect effect and will induce correlations between the random intercepts or random slopes. The equality of within‐cluster ab and c – c′ no longer holds. Correlation between random slopes implies that the within‐cluster indirect effect is conditional, interpretable at the grand mean level of the omitted variable.     

Parent–child interaction: Does parental language matter?

Although parental language and behaviour have been widely investigated, few studies have examined their unique and interactive contribution to the parent–child relationship. The current study explores how parental behaviour (sensitivity and non‐intrusiveness) and the use of parental language (exploring and control languages) correlate with parent–child dyadic mutuality. Specifically, we investigated the following questions: (1) ‘Is parental language associated with parent–child dyadic mutuality above and beyond parental behaviour?’ (2) ‘Does parental language moderate the links between parental behaviour and the parent–child dyadic mutuality?’ (3) ‘Do these differences vary between mothers and fathers?’ The sample included 65 children (M_age = 1.97 years, SD = 0.86) and their parents. We observed parental behaviour, parent–child dyadic mutuality, and the type of parental language used during videotaped in‐home observations. The results indicated that parental language and behaviours are distinct components of the parent–child interaction. Parents who used higher levels of exploring language showed higher levels of parent–child dyadic mutuality, even when accounting for parental behaviour. Use of controlling language, however, was not found to be related to the parent–child dyadic mutuality. Different moderation models were found for mothers and fathers. These results highlight the need to distinguish parental language and behaviour when assessing their contribution to the parent–child relationship.     

Exploring Different Forms of Job (Dis)Satisfaction and Their Relationship with Well‐Being,Motivation and Performance

Job satisfaction is often treated as a one‐dimensional construct. In contrast, Bruggemann ( 1974 ) postulated six distinct forms of (dis)satisfaction: four types of satisfaction (progressive, stabilised, resigned, pseudo) and two types of dissatisfaction (constructive, fixated). Despite her theory's practical relevance, few researchers have explored its assumptions or applications. The current study aimed to characterise a German‐speaking employee sample (n = 892) according to Bruggemann's theory using mixture modelling. We investigated stability of the (dis)satisfaction forms over a five‐month period, as well as their relationship with well‐being, motivation and (self‐reported) performance. We found latent clusters corresponding to most Bruggemann types, though no distinction between progressive and stabilised satisfaction was possible. While cluster membership varied over time, some clusters (e.g. resigned satisfaction) were more stable than others (e.g. constructive dissatisfaction). Overall satisfaction level explained 25–51 per cent variance in well‐being and motivation, and 13–16 per cent variance in performance. Including forms of satisfaction improved cross‐sectional prediction by 2–6 per cent explained variance. Results suggest that unfavourable consequences of job dissatisfaction may be limited to fixated—not constructive—dissatisfaction, though no consistent longitudinal effects emerged. We argue that exploring qualitative differences in job satisfaction promotes a more nuanced and potentially useful understanding of the relationship between satisfaction and work outcomes.     

A new orthorhombic approximant of the icosahedral Al–Cu–Fe quasicrystal

We report on the formation of a new crystalline approximant phase of the icosahedral (i-)Al–Cu–Fe quasicrystal. This phase is formed during sintering of Al-based composites reinforced with i-AlCuFeB quasicrystalline particles. The structure of this phase has been characterized by transmission electron microscopy (TEM) and high-resolution electron microscopy (HREM). TEM revealed that it is a B-centred orthorhombic phase with lattice parameters a = 1.166 nm, b = 1.195 nm and c = 3.44 nm. Its chemical composition, as determined by electron energy loss spectroscopy (EELS), is close to Al_76.9Cu_2.7Fe_20.4, with an average number of valence electrons per atom e/a of 1.92, similar to the value in all other approximants of the i-phase discovered thus far. Initial results on local atomic arrangements along one of its pseudo-5-fold axes are also presented.     

Rural Chinese youth during the transition into adulthood: Family dynamics and psychological adjustment

Rural youth in China experience numerous challenges during their transition into adulthood. Yet, research on this transition and its relevant influential factors is rare. Through the lens of family systems theory, this study examined the impacts of family dynamics (i.e., interparental and parent–adolescent interactions) in adolescence on the psychological adjustment of youth as they transition into adulthood. Participants were 1330 youth and their mothers in rural Gansu. In 2004, mothers completed questionnaires of interparental and parent–adolescent interactions when youth were adolescents (M_age = 15.03, SD = 1.15). In 2009, youth completed questionnaires of depression and self-esteem when they were emerging adults (M_age = 20.03, SD = 1.15). Results of structural equation modelling suggested that while interparental interactions in adolescence were not associated with the psychological adjustment of youth in emerging adulthood, positive parent–adolescent interactions in adolescence predicted better psychological adjustment of youth in emerging adulthood. Furthermore, mediation analysis showed that although interparental interactions did not directly affect the psychological adjustment of youth, they were positively associated with parent–adolescent interactions, which in turn contributed to the psychological adjustment of youth. The results reveal an enduring influence of family dynamics on psychological adjustment among rural Chinese youth during the transition into adulthood.     

Structure of a cubic phase related to Cd?Mg?rare-earth quasicrystals

The structure of a Cd₆₈Mg₁₂Dy₂₀ crystalline phase denoted as the φ-phase, which has a composition close to that of the Cd₆₆Mg₂₁Dy₁₃ icosahedral quasicrystalline phase, has been investigated by electron diffraction and scanning transmission electron microscopy (STEM). The φ phase has a fcc lattice with a = 21.6Å. High-angle annular dark-field STEM with Z contrast confirms that the phase has the Cd₄₅Sm₁₁-type structure. The atomic cluster in the structure is shown to be characterized by a Friauf polyhedron with tetrahedral symmetry.     

A model-based cluster analysis of social experiences in clinically anxious youth: links to emotional functioning

Social difficulties are commonly associated with anxiety disorders in youth, yet are not well specified in the literature. The aim of this study was to identify patterns of social experiences in clinically anxious children and examine the associations with indices of emotional functioning. A model-based cluster analysis was conducted on parent-, teacher-, and child-reports of social experiences with 64 children, ages 7–12 years (M = 8.86 years, SD = 1.59 years; 60.3% boys; 85.7% Caucasian) with a primary diagnosis of separation anxiety disorder, social phobia, and/or generalized anxiety disorder. Follow-up analyses examined cluster differences on indices of emotional functioning. Findings yielded three clusters of social experiences that were unrelated to diagnosis: (1) Unaware Children (elevated scores on parent- and teacher-reports of social difficulties but relatively low scores on child-reports, n = 12), (2) Average Functioning (relatively average scores across all informants, n = 44), and (3) Victimized and Lonely (elevated child-reports of overt and relational victimization and loneliness and relatively low scores on parent- and teacher-reports of social difficulties, n = 8). Youth in the Unaware Children cluster were rated as more emotionally dysregulated by teachers and had a greater number of diagnoses than youth in the Average Functioning group. In contrast, the Victimized and Lonely group self-reported greater frequency of negative affect and reluctance to share emotional experiences than the Average Functioning cluster. Overall, this study demonstrates that social maladjustment in clinically anxious children can manifest in a variety of ways and assessment should include multiple informants and methods.     

Room temperature ferromagnetism and photoluminescence of nanocrystalline Zn1 − xCoxO thin films prepared by sol–gel MOD

Zn_1???xCo_xO (ZC) [x?=?0, 1, 3, 5, 7 and 9?mol%] thin films were prepared by sol–gel combined metallo-organic decomposition method. The films were deposited on the Si substrate with spin-coating technique and annealed at 600?°C for 3?h. X-ray diffraction pattern shows the formation hexagonal wurtzite phase and distortion (c/a) decreases with increasing Co concentration in ZnO. The average grain size is measured using Scherer relation. Atomic force microscopy is used to confirm the formation of nanograins resulted by the use of polyethylene glycol as surfactant. The photoluminescence was recorded by using He-Cd laser of excitation wavelength 325?nm in wavelength region of 350–650?nm which exhibits some influence of Co doping on the multiplication of defects such as O vacancies, Zn interstitials and grain boundary defects. All thin films show room temperature ferromagnetism except pure ZnO which is diamagnetic and 9?mol% of Co shows paramagnetism. This behaviour is interpreted as due to fluctuations in the magnetic ordering, depending on grain size and site location in grain boundaries or oxygen vacancies.     

What is Ubuntu,? Different Interpretations among South Africans of African Descent

Abstract

In this article, I describe and systematize the different answers to the question ‘What is ubuntu,?’ that I have been able to identify among South Africans of African descent (SAADs). I show that it is possible to distinguish between two clusters of answers. The answers of the first cluster all define ubuntu, as a moral quality of a person, while the answers of the second cluster all define ubuntu, as a phenomenon (for instance a philosophy, an ethic, African humanism, or, a worldview) according to which persons are interconnected. The concept of a person is of central importance to all the answers of both clusters, which means that to understand these answers, it is decisive to raise the question of who counts, as a person according to SAADs. I show that some SAADs define all Homo sapiens, as persons, whereas others hold the view that only some Homo sapiens, count as persons: only those who are black, only those who have been incorporated into personhood, or only those who behave in a morally acceptable manner.