NASA Astrophysics Data System (ADS)
Wu, Zhihao; Lin, Youfang; Zhao, Yiji; Yan, Hongyan
2018-02-01
Networks can represent a wide range of complex systems, such as social, biological and technological systems. Link prediction is one of the most important problems in network analysis, and has attracted much research interest recently. Many link prediction methods have been proposed to solve this problem with various techniques. We can note that clustering information plays an important role in solving the link prediction problem. In previous literatures, we find node clustering coefficient appears frequently in many link prediction methods. However, node clustering coefficient is limited to describe the role of a common-neighbor in different local networks, because it cannot distinguish different clustering abilities of a node to different node pairs. In this paper, we shift our focus from nodes to links, and propose the concept of asymmetric link clustering (ALC) coefficient. Further, we improve three node clustering based link prediction methods via the concept of ALC. The experimental results demonstrate that ALC-based methods outperform node clustering based methods, especially achieving remarkable improvements on food web, hamster friendship and Internet networks. Besides, comparing with other methods, the performance of ALC-based methods are very stable in both globalized and personalized top-L link prediction tasks.
Constrained Active Learning for Anchor Link Prediction Across Multiple Heterogeneous Social Networks
Zhu, Junxing; Zhang, Jiawei; Wu, Quanyuan; Jia, Yan; Zhou, Bin; Wei, Xiaokai; Yu, Philip S.
2017-01-01
Nowadays, people are usually involved in multiple heterogeneous social networks simultaneously. Discovering the anchor links between the accounts owned by the same users across different social networks is crucial for many important inter-network applications, e.g., cross-network link transfer and cross-network recommendation. Many different supervised models have been proposed to predict anchor links so far, but they are effective only when the labeled anchor links are abundant. However, in real scenarios, such a requirement can hardly be met and most anchor links are unlabeled, since manually labeling the inter-network anchor links is quite costly and tedious. To overcome such a problem and utilize the numerous unlabeled anchor links in model building, in this paper, we introduce the active learning based anchor link prediction problem. Different from the traditional active learning problems, due to the one-to-one constraint on anchor links, if an unlabeled anchor link a=(u,v) is identified as positive (i.e., existing), all the other unlabeled anchor links incident to account u or account v will be negative (i.e., non-existing) automatically. Viewed in such a perspective, asking for the labels of potential positive anchor links in the unlabeled set will be rewarding in the active anchor link prediction problem. Various novel anchor link information gain measures are defined in this paper, based on which several constraint active anchor link prediction methods are introduced. Extensive experiments have been done on real-world social network datasets to compare the performance of these methods with state-of-art anchor link prediction methods. The experimental results show that the proposed Mean-entropy-based Constrained Active Learning (MC) method can outperform other methods with significant advantages. PMID:28771201
Zhu, Junxing; Zhang, Jiawei; Wu, Quanyuan; Jia, Yan; Zhou, Bin; Wei, Xiaokai; Yu, Philip S
2017-08-03
Nowadays, people are usually involved in multiple heterogeneous social networks simultaneously. Discovering the anchor links between the accounts owned by the same users across different social networks is crucial for many important inter-network applications, e.g., cross-network link transfer and cross-network recommendation. Many different supervised models have been proposed to predict anchor links so far, but they are effective only when the labeled anchor links are abundant. However, in real scenarios, such a requirement can hardly be met and most anchor links are unlabeled, since manually labeling the inter-network anchor links is quite costly and tedious. To overcome such a problem and utilize the numerous unlabeled anchor links in model building, in this paper, we introduce the active learning based anchor link prediction problem. Different from the traditional active learning problems, due to the one-to-one constraint on anchor links, if an unlabeled anchor link a = ( u , v ) is identified as positive (i.e., existing), all the other unlabeled anchor links incident to account u or account v will be negative (i.e., non-existing) automatically. Viewed in such a perspective, asking for the labels of potential positive anchor links in the unlabeled set will be rewarding in the active anchor link prediction problem. Various novel anchor link information gain measures are defined in this paper, based on which several constraint active anchor link prediction methods are introduced. Extensive experiments have been done on real-world social network datasets to compare the performance of these methods with state-of-art anchor link prediction methods. The experimental results show that the proposed Mean-entropy-based Constrained Active Learning (MC) method can outperform other methods with significant advantages.
A link prediction approach to cancer drug sensitivity prediction.
Turki, Turki; Wei, Zhi
2017-10-03
Predicting the response to a drug for cancer disease patients based on genomic information is an important problem in modern clinical oncology. This problem occurs in part because many available drug sensitivity prediction algorithms do not consider better quality cancer cell lines and the adoption of new feature representations; both lead to the accurate prediction of drug responses. By predicting accurate drug responses to cancer, oncologists gain a more complete understanding of the effective treatments for each patient, which is a core goal in precision medicine. In this paper, we model cancer drug sensitivity as a link prediction, which is shown to be an effective technique. We evaluate our proposed link prediction algorithms and compare them with an existing drug sensitivity prediction approach based on clinical trial data. The experimental results based on the clinical trial data show the stability of our link prediction algorithms, which yield the highest area under the ROC curve (AUC) and are statistically significant. We propose a link prediction approach to obtain new feature representation. Compared with an existing approach, the results show that incorporating the new feature representation to the link prediction algorithms has significantly improved the performance.
Predicting missing links via correlation between nodes
NASA Astrophysics Data System (ADS)
Liao, Hao; Zeng, An; Zhang, Yi-Cheng
2015-10-01
As a fundamental problem in many different fields, link prediction aims to estimate the likelihood of an existing link between two nodes based on the observed information. Since this problem is related to many applications ranging from uncovering missing data to predicting the evolution of networks, link prediction has been intensively investigated recently and many methods have been proposed so far. The essential challenge of link prediction is to estimate the similarity between nodes. Most of the existing methods are based on the common neighbor index and its variants. In this paper, we propose to calculate the similarity between nodes by the Pearson correlation coefficient. This method is found to be very effective when applied to calculate similarity based on high order paths. We finally fuse the correlation-based method with the resource allocation method, and find that the combined method can substantially outperform the existing methods, especially in sparse networks.
NASA Astrophysics Data System (ADS)
Mushkin, I.; Solomon, S.
2017-10-01
We study the inverse contagion problem (ICP). As opposed to the direct contagion problem, in which the network structure is known and the question is when each node will be contaminated, in the inverse problem the links of the network are unknown but a sequence of contagion histories (the times when each node was contaminated) is observed. We consider two versions of the ICP: The strong problem (SICP), which is the reconstruction of the network and has been studied before, and the weak problem (WICP), which requires "only" the prediction (at each time step) of the nodes that will be contaminated at the next time step (this is often the real life situation in which a contagion is observed and predictions are made in real time). Moreover, our focus is on analyzing the increasing accuracy of the solution, as a function of the number of contagion histories already observed. For simplicity, we discuss the simplest (deterministic and synchronous) contagion dynamics and the simplest solution algorithm, which we have applied to different network types. The main result of this paper is that the complex problem of the convergence of the ICP for a network can be reduced to an individual property of pairs of nodes: the "false link difficulty". By definition, given a pair of unlinked nodes i and j, the difficulty of the false link (i,j) is the probability that in a random contagion history, the nodes i and j are not contaminated at the same time step (or at consecutive time steps). In other words, the "false link difficulty" of a non-existing network link is the probability that the observations during a random contagion history would not rule out that link. This probability is relatively straightforward to calculate, and in most instances relies only on the relative positions of the two nodes (i,j) and not on the entire network structure. We have observed the distribution of false link difficulty for various network types, estimated it theoretically and confronted it (successfully) with the numerical simulations. Based on it, we estimated analytically the convergence of the ICP solution (as a function of the number of contagion histories observed), and found it to be in perfect agreement with simulation results. Finally, the most important insight we obtained is that SICP and WICP are have quite different properties: if one in interested only in the operational aspect of predicting how contagion will spread, the links which are most difficult to decide about are the least influential on contagion dynamics. In other words, the parts of the network which are harder to reconstruct are also least important for predicting the contagion dynamics, up to the point where a (large) constant number of false links in the network (i.e. non-convergence of the network reconstruction procedure) implies a zero rate of the node contagion prediction errors (perfect convergence of the WICP). Thus, the contagion prediction problem (WICP) difficulty is very different from the network reconstruction problem (SICP), in as far as links which are difficult to reconstruct are quite harmless in terms of contagion prediction capability (WICP).
Graph regularized nonnegative matrix factorization for temporal link prediction in dynamic networks
NASA Astrophysics Data System (ADS)
Ma, Xiaoke; Sun, Penggang; Wang, Yu
2018-04-01
Many networks derived from society and nature are temporal and incomplete. The temporal link prediction problem in networks is to predict links at time T + 1 based on a given temporal network from time 1 to T, which is essential to important applications. The current algorithms either predict the temporal links by collapsing the dynamic networks or collapsing features derived from each network, which are criticized for ignoring the connection among slices. to overcome the issue, we propose a novel graph regularized nonnegative matrix factorization algorithm (GrNMF) for the temporal link prediction problem without collapsing the dynamic networks. To obtain the feature for each network from 1 to t, GrNMF factorizes the matrix associated with networks by setting the rest networks as regularization, which provides a better way to characterize the topological information of temporal links. Then, the GrNMF algorithm collapses the feature matrices to predict temporal links. Compared with state-of-the-art methods, the proposed algorithm exhibits significantly improved accuracy by avoiding the collapse of temporal networks. Experimental results of a number of artificial and real temporal networks illustrate that the proposed method is not only more accurate but also more robust than state-of-the-art approaches.
A novel time series link prediction method: Learning automata approach
NASA Astrophysics Data System (ADS)
Moradabadi, Behnaz; Meybodi, Mohammad Reza
2017-09-01
Link prediction is a main social network challenge that uses the network structure to predict future links. The common link prediction approaches to predict hidden links use a static graph representation where a snapshot of the network is analyzed to find hidden or future links. For example, similarity metric based link predictions are a common traditional approach that calculates the similarity metric for each non-connected link and sort the links based on their similarity metrics and label the links with higher similarity scores as the future links. Because people activities in social networks are dynamic and uncertainty, and the structure of the networks changes over time, using deterministic graphs for modeling and analysis of the social network may not be appropriate. In the time-series link prediction problem, the time series link occurrences are used to predict the future links In this paper, we propose a new time series link prediction based on learning automata. In the proposed algorithm for each link that must be predicted there is one learning automaton and each learning automaton tries to predict the existence or non-existence of the corresponding link. To predict the link occurrence in time T, there is a chain consists of stages 1 through T - 1 and the learning automaton passes from these stages to learn the existence or non-existence of the corresponding link. Our preliminary link prediction experiments with co-authorship and email networks have provided satisfactory results when time series link occurrences are considered.
ERIC Educational Resources Information Center
Waller, Rebecca; Dishion, Thomas J.; Shaw, Daniel S.; Gardner, Frances; Wilson, Melvin N.; Hyde, Luke W.
2016-01-01
Callous-unemotional (CU) behavior has been linked to behavior problems in children and adolescents. However, few studies have examined whether CU behavior in "early childhood" predicts behavior problems or CU behavior in "late childhood". This study examined whether indicators of CU behavior at ages 2-4 predicted aggression,…
Retweets as a Predictor of Relationships among Users on Social Media.
Tsugawa, Sho; Kito, Kosuke
2017-01-01
Link prediction is the problem of detecting missing links or predicting future link formation in a network. Application of link prediction to social media, such as Twitter and Facebook, is useful both for developing novel services and for sociological analyses. While most existing research on link prediction uses only the social network topology for the prediction, in social media, records of user activities such as posting, replying, and reposting are available. These records are expected to reflect user interest, and so incorporating them should improve link prediction. However, research into link prediction using the records of user activities is still in its infancy, and the effectiveness of such records for link prediction has not been fully explored. In this study, we focus in particular on records of reposting as a promising source that could be useful for link prediction, and investigate their effectiveness for link prediction on the popular social media platform Twitter. Our results show that (1) the prediction accuracy of techniques using reposting records is higher than that of popular topology-based techniques such as common neighbors and resource allocation for actively retweeting users, (2) the accuracy of link prediction techniques that use network topology alone can be improved by incorporating reposting records.
Retweets as a Predictor of Relationships among Users on Social Media
Kito, Kosuke
2017-01-01
Link prediction is the problem of detecting missing links or predicting future link formation in a network. Application of link prediction to social media, such as Twitter and Facebook, is useful both for developing novel services and for sociological analyses. While most existing research on link prediction uses only the social network topology for the prediction, in social media, records of user activities such as posting, replying, and reposting are available. These records are expected to reflect user interest, and so incorporating them should improve link prediction. However, research into link prediction using the records of user activities is still in its infancy, and the effectiveness of such records for link prediction has not been fully explored. In this study, we focus in particular on records of reposting as a promising source that could be useful for link prediction, and investigate their effectiveness for link prediction on the popular social media platform Twitter. Our results show that (1) the prediction accuracy of techniques using reposting records is higher than that of popular topology-based techniques such as common neighbors and resource allocation for actively retweeting users, (2) the accuracy of link prediction techniques that use network topology alone can be improved by incorporating reposting records. PMID:28107489
Exploiting Information Diffusion Feature for Link Prediction in Sina Weibo
NASA Astrophysics Data System (ADS)
Li, Dong; Zhang, Yongchao; Xu, Zhiming; Chu, Dianhui; Li, Sheng
2016-01-01
The rapid development of online social networks (e.g., Twitter and Facebook) has promoted research related to social networks in which link prediction is a key problem. Although numerous attempts have been made for link prediction based on network structure, node attribute and so on, few of the current studies have considered the impact of information diffusion on link creation and prediction. This paper mainly addresses Sina Weibo, which is the largest microblog platform with Chinese characteristics, and proposes the hypothesis that information diffusion influences link creation and verifies the hypothesis based on real data analysis. We also detect an important feature from the information diffusion process, which is used to promote link prediction performance. Finally, the experimental results on Sina Weibo dataset have demonstrated the effectiveness of our methods.
Exploiting Information Diffusion Feature for Link Prediction in Sina Weibo.
Li, Dong; Zhang, Yongchao; Xu, Zhiming; Chu, Dianhui; Li, Sheng
2016-01-28
The rapid development of online social networks (e.g., Twitter and Facebook) has promoted research related to social networks in which link prediction is a key problem. Although numerous attempts have been made for link prediction based on network structure, node attribute and so on, few of the current studies have considered the impact of information diffusion on link creation and prediction. This paper mainly addresses Sina Weibo, which is the largest microblog platform with Chinese characteristics, and proposes the hypothesis that information diffusion influences link creation and verifies the hypothesis based on real data analysis. We also detect an important feature from the information diffusion process, which is used to promote link prediction performance. Finally, the experimental results on Sina Weibo dataset have demonstrated the effectiveness of our methods.
A class-based link prediction using Distance Dependent Chinese Restaurant Process
NASA Astrophysics Data System (ADS)
Andalib, Azam; Babamir, Seyed Morteza
2016-08-01
One of the important tasks in relational data analysis is link prediction which has been successfully applied on many applications such as bioinformatics, information retrieval, etc. The link prediction is defined as predicting the existence or absence of edges between nodes of a network. In this paper, we propose a novel method for link prediction based on Distance Dependent Chinese Restaurant Process (DDCRP) model which enables us to utilize the information of the topological structure of the network such as shortest path and connectivity of the nodes. We also propose a new Gibbs sampling algorithm for computing the posterior distribution of the hidden variables based on the training data. Experimental results on three real-world datasets show the superiority of the proposed method over other probabilistic models for link prediction problem.
ERIC Educational Resources Information Center
Lewis, Gary J.; Asbury, Kathryn; Plomin, Robert
2017-01-01
Background: Childhood behavior problems predict subsequent educational achievement; however, little research has examined the etiology of these links using a longitudinal twin design. Moreover, it is unknown whether genetic and environmental innovations provide incremental prediction for educational achievement from childhood to adolescence.…
Revealing how network structure affects accuracy of link prediction
NASA Astrophysics Data System (ADS)
Yang, Jin-Xuan; Zhang, Xiao-Dong
2017-08-01
Link prediction plays an important role in network reconstruction and network evolution. The network structure affects the accuracy of link prediction, which is an interesting problem. In this paper we use common neighbors and the Gini coefficient to reveal the relation between them, which can provide a good reference for the choice of a suitable link prediction algorithm according to the network structure. Moreover, the statistical analysis reveals correlation between the common neighbors index, Gini coefficient index and other indices to describe the network structure, such as Laplacian eigenvalues, clustering coefficient, degree heterogeneity, and assortativity of network. Furthermore, a new method to predict missing links is proposed. The experimental results show that the proposed algorithm yields better prediction accuracy and robustness to the network structure than existing currently used methods for a variety of real-world networks.
Link prediction with node clustering coefficient
NASA Astrophysics Data System (ADS)
Wu, Zhihao; Lin, Youfang; Wang, Jing; Gregory, Steve
2016-06-01
Predicting missing links in incomplete complex networks efficiently and accurately is still a challenging problem. The recently proposed Cannistrai-Alanis-Ravai (CAR) index shows the power of local link/triangle information in improving link-prediction accuracy. Inspired by the idea of employing local link/triangle information, we propose a new similarity index with more local structure information. In our method, local link/triangle structure information can be conveyed by clustering coefficient of common-neighbors directly. The reason why clustering coefficient has good effectiveness in estimating the contribution of a common-neighbor is that it employs links existing between neighbors of a common-neighbor and these links have the same structural position with the candidate link to this common-neighbor. In our experiments, three estimators: precision, AUP and AUC are used to evaluate the accuracy of link prediction algorithms. Experimental results on ten tested networks drawn from various fields show that our new index is more effective in predicting missing links than CAR index, especially for networks with low correlation between number of common-neighbors and number of links between common-neighbors.
Conway, Anne; Modrek, Anahid; Gorroochurn, Prakash
2018-02-01
Theory underscores the importance of parenting in sleep development, but few studies have examined whether links vary by temperament. To address this gap, we tested whether potential links between early maternal sensitivity and early adolescent sleep problems varied by child negative emotionality and delay of gratification. Using data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development (N = 820), we found that high maternal sensitivity predicted fewer bedtime problems and longer sleep duration at 6th grade for toddlers with high negative emotionality, whereas low maternal sensitivity predicted the reverse. No differences were observed for low negative emotionality. Moreover, delay of gratification predicted fewer bedtime problems at 6th grade, but did not moderate associations between maternal sensitivity, negative emotionality, and sleep. Findings demonstrate that high, but not low, negative emotionality renders toddlers differentially susceptible and receptive to maternal sensitivity in relation to sleep.
Link Prediction in Criminal Networks: A Tool for Criminal Intelligence Analysis
Berlusconi, Giulia; Calderoni, Francesco; Parolini, Nicola; Verani, Marco; Piccardi, Carlo
2016-01-01
The problem of link prediction has recently received increasing attention from scholars in network science. In social network analysis, one of its aims is to recover missing links, namely connections among actors which are likely to exist but have not been reported because data are incomplete or subject to various types of uncertainty. In the field of criminal investigations, problems of incomplete information are encountered almost by definition, given the obvious anti-detection strategies set up by criminals and the limited investigative resources. In this paper, we work on a specific dataset obtained from a real investigation, and we propose a strategy to identify missing links in a criminal network on the basis of the topological analysis of the links classified as marginal, i.e. removed during the investigation procedure. The main assumption is that missing links should have opposite features with respect to marginal ones. Measures of node similarity turn out to provide the best characterization in this sense. The inspection of the judicial source documents confirms that the predicted links, in most instances, do relate actors with large likelihood of co-participation in illicit activities. PMID:27104948
Wagner, Nicholas J; Hastings, Paul D; Rubin, Kenneth H
2017-11-29
Callous-unemotional (CU) traits are one meaningful risk factor which helps to explain heterogeneity in the emergence of externalizing behavior problems. While the extant literature demonstrates links between early CU traits and later externalizing problems, there is a dearth of research examining for whom early CU traits confer risk. Data from a longitudinal study (n = 108) were used to examine the extent to which parasympathetic functioning moderated links between CU traits in toddlerhood (m age = 24.99 months) and externalizing behavior problems at preschool-age (m age = 51 months). Neither CU traits nor parasympathetic functioning at age 2 directly predicted later externalizing behaviors. However, results show that high levels of CU traits predict elevated externalizing behavior problems, but only for toddlers exhibiting either high baseline respiratory sinus arrhythmia (RSA) or little to no RSA suppression in response to a fear stimulus.
Predicting the evolution of complex networks via similarity dynamics
NASA Astrophysics Data System (ADS)
Wu, Tao; Chen, Leiting; Zhong, Linfeng; Xian, Xingping
2017-01-01
Almost all real-world networks are subject to constant evolution, and plenty of them have been investigated empirically to uncover the underlying evolution mechanism. However, the evolution prediction of dynamic networks still remains a challenging problem. The crux of this matter is to estimate the future network links of dynamic networks. This paper studies the evolution prediction of dynamic networks with link prediction paradigm. To estimate the likelihood of the existence of links more accurate, an effective and robust similarity index is presented by exploiting network structure adaptively. Moreover, most of the existing link prediction methods do not make a clear distinction between future links and missing links. In order to predict the future links, the networks are regarded as dynamic systems in this paper, and a similarity updating method, spatial-temporal position drift model, is developed to simulate the evolutionary dynamics of node similarity. Then the updated similarities are used as input information for the future links' likelihood estimation. Extensive experiments on real-world networks suggest that the proposed similarity index performs better than baseline methods and the position drift model performs well for evolution prediction in real-world evolving networks.
The degree-related clustering coefficient and its application to link prediction
NASA Astrophysics Data System (ADS)
Liu, Yangyang; Zhao, Chengli; Wang, Xiaojie; Huang, Qiangjuan; Zhang, Xue; Yi, Dongyun
2016-07-01
Link prediction plays a significant role in explaining the evolution of networks. However it is still a challenging problem that has been addressed only with topological information in recent years. Based on the belief that network nodes with a great number of common neighbors are more likely to be connected, many similarity indices have achieved considerable accuracy and efficiency. Motivated by the natural assumption that the effect of missing links on the estimation of a node's clustering ability could be related to node degree, in this paper, we propose a degree-related clustering coefficient index to quantify the clustering ability of nodes. Unlike the classical clustering coefficient, our new coefficient is highly robust when the observed bias of links is considered. Furthermore, we propose a degree-related clustering ability path (DCP) index, which applies the proposed coefficient to the link prediction problem. Experiments on 12 real-world networks show that our proposed method is highly accurate and robust compared with four common-neighbor-based similarity indices (Common Neighbors(CN), Adamic-Adar(AA), Resource Allocation(RA), and Preferential Attachment(PA)), and the recently introduced clustering ability (CA) index.
Link prediction based on local weighted paths for complex networks
NASA Astrophysics Data System (ADS)
Yao, Yabing; Zhang, Ruisheng; Yang, Fan; Yuan, Yongna; Hu, Rongjing; Zhao, Zhili
As a significant problem in complex networks, link prediction aims to find the missing and future links between two unconnected nodes by estimating the existence likelihood of potential links. It plays an important role in understanding the evolution mechanism of networks and has broad applications in practice. In order to improve prediction performance, a variety of structural similarity-based methods that rely on different topological features have been put forward. As one topological feature, the path information between node pairs is utilized to calculate the node similarity. However, many path-dependent methods neglect the different contributions of paths for a pair of nodes. In this paper, a local weighted path (LWP) index is proposed to differentiate the contributions between paths. The LWP index considers the effect of the link degrees of intermediate links and the connectivity influence of intermediate nodes on paths to quantify the path weight in the prediction procedure. The experimental results on 12 real-world networks show that the LWP index outperforms other seven prediction baselines.
NASA Astrophysics Data System (ADS)
Yasami, Yasser; Safaei, Farshad
2018-02-01
The traditional complex network theory is particularly focused on network models in which all network constituents are dealt with equivalently, while fail to consider the supplementary information related to the dynamic properties of the network interactions. This is a main constraint leading to incorrect descriptions of some real-world phenomena or incomplete capturing the details of certain real-life problems. To cope with the problem, this paper addresses the multilayer aspects of dynamic complex networks by analyzing the properties of intrinsically multilayered co-authorship networks, DBLP and Astro Physics, and presenting a novel multilayer model of dynamic complex networks. The model examines the layers evolution (layers birth/death process and lifetime) throughout the network evolution. Particularly, this paper models the evolution of each node's membership in different layers by an Infinite Factorial Hidden Markov Model considering feature cascade, and thereby formulates the link generation process for intra-layer and inter-layer links. Although adjacency matrixes are useful to describe the traditional single-layer networks, such a representation is not sufficient to describe and analyze the multilayer dynamic networks. This paper also extends a generalized mathematical infrastructure to address the problems issued by multilayer complex networks. The model inference is performed using some Markov Chain Monte Carlo sampling strategies, given synthetic and real complex networks data. Experimental results indicate a tremendous improvement in the performance of the proposed multilayer model in terms of sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios, F1-score, Matthews correlation coefficient, and accuracy for two important applications of missing link prediction and future link forecasting. The experimental results also indicate the strong predictivepower of the proposed model for the application of cascade prediction in terms of accuracy.
Plumlee, Geoffrey S.; Morman, Suzette A.
2011-01-01
Historical mining and mineral processing have been linked definitively to health problems resulting from occupational and environmental exposures to mine wastes. Modern mining and processing methods, when properly designed and implemented, prevent or greatly reduce potential environmental health impacts. However, particularly in developing countries, there are examples of health problems linked to recent mining. In other cases, recent mining has been blamed for health problems but no clear links have been found. The types and abundances of potential toxicants in mine wastes are predictably influenced by the geologic characteristics of the deposit being mined. Hence, Earth scientists can help understand, anticipate, and mitigate potential health issues associated with mining and mineral processing.
On the estimation of risk associated with an attenuation prediction
NASA Technical Reports Server (NTRS)
Crane, R. K.
1992-01-01
Viewgraphs from a presentation on the estimation of risk associated with an attenuation prediction is presented. Topics covered include: link failure - attenuation exceeding a specified threshold for a specified time interval or intervals; risk - the probability of one or more failures during the lifetime of the link or during a specified accounting interval; the problem - modeling the probability of attenuation by rainfall to provide a prediction of the attenuation threshold for a specified risk; and an accounting for the inadequacy of a model or models.
A new similarity measure for link prediction based on local structures in social networks
NASA Astrophysics Data System (ADS)
Aghabozorgi, Farshad; Khayyambashi, Mohammad Reza
2018-07-01
Link prediction is a fundamental problem in social network analysis. There exist a variety of techniques for link prediction which applies the similarity measures to estimate proximity of vertices in the network. Complex networks like social networks contain structural units named network motifs. In this study, a newly developed similarity measure is proposed where these structural units are applied as the source of similarity estimation. This similarity measure is tested through a supervised learning experiment framework, where other similarity measures are compared with this similarity measure. The classification model trained with this similarity measure outperforms others of its kind.
Improving personalized link prediction by hybrid diffusion
NASA Astrophysics Data System (ADS)
Liu, Jin-Hu; Zhu, Yu-Xiao; Zhou, Tao
2016-04-01
Inspired by traditional link prediction and to solve the problem of recommending friends in social networks, we introduce the personalized link prediction in this paper, in which each individual will get equal number of diversiform predictions. While the performances of many classical algorithms are not satisfactory under this framework, thus new algorithms are in urgent need. Motivated by previous researches in other fields, we generalize heat conduction process to the framework of personalized link prediction and find that this method outperforms many classical similarity-based algorithms, especially in the performance of diversity. In addition, we demonstrate that adding one ground node that is supposed to connect all the nodes in the system will greatly benefit the performance of heat conduction. Finally, better hybrid algorithms composed of local random walk and heat conduction have been proposed. Numerical results show that the hybrid algorithms can outperform other algorithms simultaneously in all four adopted metrics: AUC, precision, recall and hamming distance. In a word, this work may shed some light on the in-depth understanding of the effect of physical processes in personalized link prediction.
Link prediction in multiplex online social networks
NASA Astrophysics Data System (ADS)
Jalili, Mahdi; Orouskhani, Yasin; Asgari, Milad; Alipourfard, Nazanin; Perc, Matjaž
2017-02-01
Online social networks play a major role in modern societies, and they have shaped the way social relationships evolve. Link prediction in social networks has many potential applications such as recommending new items to users, friendship suggestion and discovering spurious connections. Many real social networks evolve the connections in multiple layers (e.g. multiple social networking platforms). In this article, we study the link prediction problem in multiplex networks. As an example, we consider a multiplex network of Twitter (as a microblogging service) and Foursquare (as a location-based social network). We consider social networks of the same users in these two platforms and develop a meta-path-based algorithm for predicting the links. The connectivity information of the two layers is used to predict the links in Foursquare network. Three classical classifiers (naive Bayes, support vector machines (SVM) and K-nearest neighbour) are used for the classification task. Although the networks are not highly correlated in the layers, our experiments show that including the cross-layer information significantly improves the prediction performance. The SVM classifier results in the best performance with an average accuracy of 89%.
Link prediction in multiplex online social networks.
Jalili, Mahdi; Orouskhani, Yasin; Asgari, Milad; Alipourfard, Nazanin; Perc, Matjaž
2017-02-01
Online social networks play a major role in modern societies, and they have shaped the way social relationships evolve. Link prediction in social networks has many potential applications such as recommending new items to users, friendship suggestion and discovering spurious connections. Many real social networks evolve the connections in multiple layers (e.g. multiple social networking platforms). In this article, we study the link prediction problem in multiplex networks. As an example, we consider a multiplex network of Twitter (as a microblogging service) and Foursquare (as a location-based social network). We consider social networks of the same users in these two platforms and develop a meta-path-based algorithm for predicting the links. The connectivity information of the two layers is used to predict the links in Foursquare network. Three classical classifiers (naive Bayes, support vector machines (SVM) and K-nearest neighbour) are used for the classification task. Although the networks are not highly correlated in the layers, our experiments show that including the cross-layer information significantly improves the prediction performance. The SVM classifier results in the best performance with an average accuracy of 89%.
A comprehensive comparison of network similarities for link prediction and spurious link elimination
NASA Astrophysics Data System (ADS)
Zhang, Peng; Qiu, Dan; Zeng, An; Xiao, Jinghua
2018-06-01
Identifying missing interactions in complex networks, known as link prediction, is realized by estimating the likelihood of the existence of a link between two nodes according to the observed links and nodes' attributes. Similar approaches have also been employed to identify and remove spurious links in networks which is crucial for improving the reliability of network data. In network science, the likelihood for two nodes having a connection strongly depends on their structural similarity. The key to address these two problems thus becomes how to objectively measure the similarity between nodes in networks. In the literature, numerous network similarity metrics have been proposed and their accuracy has been discussed independently in previous works. In this paper, we systematically compare the accuracy of 18 similarity metrics in both link prediction and spurious link elimination when the observed networks are very sparse or consist of inaccurate linking information. Interestingly, some methods have high prediction accuracy, they tend to perform low accuracy in identification spurious interaction. We further find that methods can be classified into several cluster according to their behaviors. This work is useful for guiding future use of these similarity metrics for different purposes.
Link-prediction to tackle the boundary specification problem in social network surveys
De Wilde, Philippe; Buarque de Lima-Neto, Fernando
2017-01-01
Diffusion processes in social networks often cause the emergence of global phenomena from individual behavior within a society. The study of those global phenomena and the simulation of those diffusion processes frequently require a good model of the global network. However, survey data and data from online sources are often restricted to single social groups or features, such as age groups, single schools, companies, or interest groups. Hence, a modeling approach is required that extrapolates the locally restricted data to a global network model. We tackle this Missing Data Problem using Link-Prediction techniques from social network research, network generation techniques from the area of Social Simulation, as well as a combination of both. We found that techniques employing less information may be more adequate to solve this problem, especially when data granularity is an issue. We validated the network models created with our techniques on a number of real-world networks, investigating degree distributions as well as the likelihood of links given the geographical distance between two nodes. PMID:28426826
Gershoff, Elizabeth T; Sattler, Kierra M P; Ansari, Arya
2018-01-01
Establishing causal links when experiments are not feasible is an important challenge for psychology researchers. The question of whether parents' spanking causes children's externalizing behavior problems poses such a challenge because randomized experiments of spanking are unethical, and correlational studies cannot rule out potential selection factors. This study used propensity score matching based on the lifetime prevalence and recent incidence of spanking in a large and nationally representative sample ( N = 12,112) as well as lagged dependent variables to get as close to causal estimates outside an experiment as possible. Whether children were spanked at the age of 5 years predicted increases in externalizing behavior problems by ages 6 and 8, even after the groups based on spanking prevalence or incidence were matched on a range of sociodemographic, family, and cultural characteristics and children's initial behavior problems. These statistically rigorous methods yield the conclusion that spanking predicts a deterioration of children's externalizing behavior over time.
McCoy, Allison B; Wright, Adam; Rogith, Deevakar; Fathiamini, Safa; Ottenbacher, Allison J; Sittig, Dean F
2014-04-01
Correlation of data within electronic health records is necessary for implementation of various clinical decision support functions, including patient summarization. A key type of correlation is linking medications to clinical problems; while some databases of problem-medication links are available, they are not robust and depend on problems and medications being encoded in particular terminologies. Crowdsourcing represents one approach to generating robust knowledge bases across a variety of terminologies, but more sophisticated approaches are necessary to improve accuracy and reduce manual data review requirements. We sought to develop and evaluate a clinician reputation metric to facilitate the identification of appropriate problem-medication pairs through crowdsourcing without requiring extensive manual review. We retrieved medications from our clinical data warehouse that had been prescribed and manually linked to one or more problems by clinicians during e-prescribing between June 1, 2010 and May 31, 2011. We identified measures likely to be associated with the percentage of accurate problem-medication links made by clinicians. Using logistic regression, we created a metric for identifying clinicians who had made greater than or equal to 95% appropriate links. We evaluated the accuracy of the approach by comparing links made by those physicians identified as having appropriate links to a previously manually validated subset of problem-medication pairs. Of 867 clinicians who asserted a total of 237,748 problem-medication links during the study period, 125 had a reputation metric that predicted the percentage of appropriate links greater than or equal to 95%. These clinicians asserted a total of 2464 linked problem-medication pairs (983 distinct pairs). Compared to a previously validated set of problem-medication pairs, the reputation metric achieved a specificity of 99.5% and marginally improved the sensitivity of previously described knowledge bases. A reputation metric may be a valuable measure for identifying high quality clinician-entered, crowdsourced data. Copyright © 2013 Elsevier Inc. All rights reserved.
McCoy, Allison B.; Wright, Adam; Rogith, Deevakar; Fathiamini, Safa; Ottenbacher, Allison J.; Sittig, Dean F.
2014-01-01
Background Correlation of data within electronic health records is necessary for implementation of various clinical decision support functions, including patient summarization. A key type of correlation is linking medications to clinical problems; while some databases of problem-medication links are available, they are not robust and depend on problems and medications being encoded in particular terminologies. Crowdsourcing represents one approach to generating robust knowledge bases across a variety of terminologies, but more sophisticated approaches are necessary to improve accuracy and reduce manual data review requirements. Objective We sought to develop and evaluate a clinician reputation metric to facilitate the identification of appropriate problem-medication pairs through crowdsourcing without requiring extensive manual review. Approach We retrieved medications from our clinical data warehouse that had been prescribed and manually linked to one or more problems by clinicians during e-prescribing between June 1, 2010 and May 31, 2011. We identified measures likely to be associated with the percentage of accurate problem-medication links made by clinicians. Using logistic regression, we created a metric for identifying clinicians who had made greater than or equal to 95% appropriate links. We evaluated the accuracy of the approach by comparing links made by those physicians identified as having appropriate links to a previously manually validated subset of problem-medication pairs. Results Of 867 clinicians who asserted a total of 237,748 problem-medication links during the study period, 125 had a reputation metric that predicted the percentage of appropriate links greater than or equal to 95%. These clinicians asserted a total of 2464 linked problem-medication pairs (983 distinct pairs). Compared to a previously validated set of problem-medication pairs, the reputation metric achieved a specificity of 99.5% and marginally improved the sensitivity of previously described knowledge bases. Conclusion A reputation metric may be a valuable measure for identifying high quality clinician-entered, crowdsourced data. PMID:24321170
Soft Computing Methods for Disulfide Connectivity Prediction.
Márquez-Chamorro, Alfonso E; Aguilar-Ruiz, Jesús S
2015-01-01
The problem of protein structure prediction (PSP) is one of the main challenges in structural bioinformatics. To tackle this problem, PSP can be divided into several subproblems. One of these subproblems is the prediction of disulfide bonds. The disulfide connectivity prediction problem consists in identifying which nonadjacent cysteines would be cross-linked from all possible candidates. Determining the disulfide bond connectivity between the cysteines of a protein is desirable as a previous step of the 3D PSP, as the protein conformational search space is highly reduced. The most representative soft computing approaches for the disulfide bonds connectivity prediction problem of the last decade are summarized in this paper. Certain aspects, such as the different methodologies based on soft computing approaches (artificial neural network or support vector machine) or features of the algorithms, are used for the classification of these methods.
ERIC Educational Resources Information Center
Lahey, Benjamin B.; Van Hulle, Carol A.; Rathouz, Paul J.; Rodgers, Joseph Lee; D'Onofrio, Brian M.; Waldman, Irwin D.
2009-01-01
Inattentive-hyperactive and oppositional behavior have been hypothesized to be developmental precursors to conduct problems. We tested these hypotheses using a longitudinal sample of 6,466 offspring of women selected from nationally representative US households. Conduct problems across 8-13 years were robustly predicted by conduct problems at 4-7…
Okado, Yuko; Bierman, Karen L
2015-05-01
To investigate the differential emergence of antisocial behaviors and mood dysregulation among children with externalizing problems, the present study prospectively followed 317 high-risk children with early externalizing problems from school entry (ages 5-7) to late adolescence (ages 17-19). Latent class analysis conducted on their conduct and mood symptoms in late adolescence revealed three distinct patterns of symptoms, characterized by: 1) criminal offenses, conduct disorder symptoms, and elevated anger ("conduct problems"), 2) elevated anger, dysphoric mood, and suicidal ideation ("mood dysregulation"), and 3) low levels of severe conduct and mood symptoms. A diathesis-stress model predicting the first two outcomes was tested. Elevated overt aggression at school entry uniquely predicted conduct problems in late adolescence, whereas elevated emotion dysregulation at school entry uniquely predicted mood dysregulation in late adolescence. Experiences of low parental warmth and peer rejection in middle childhood moderated the link between early emotion dysregulation and later mood dysregulation but did not moderate the link between early overt aggression and later conduct problems. Thus, among children with early externalizing behavior problems, increased risk for later antisocial behavior or mood dysfunction may be identifiable in early childhood based on levels of overt aggression and emotion dysregulation. For children with early emotion dysregulation, however, increased risk for mood dysregulation characterized by anger, dysphoric mood, and suicidality--possibly indicative of disruptive mood dysregulation disorder--emerges only in the presence of low parental warmth and/or peer rejection during middle childhood.
Mood instability as a precursor to depressive illness: A prospective and mediational analysis.
Marwaha, Steven; Balbuena, Lloyd; Winsper, Catherine; Bowen, Rudy
2015-06-01
Mood instability levels are high in depression, but temporal precedence and potential mechanisms are unknown. Hypotheses tested were as follows: (1) mood instability is associated with depression cross-sectionally, (2) mood instability predicts new onset and maintenance of depression prospectively and (3) the mood instability and depression link are mediated by sleep problems, alcohol abuse and life events. Data from the National Psychiatric Morbidity Survey 2000 at baseline (N = 8580) and 18-month follow-up (N = 2413) were used. Regression modeling controlling for socio-demographic factors, anxiety and hypomanic mood was conducted. Multiple mediational analyses were used to test our conceptual path model. Mood instability was associated with depression cross-sectionally (odds ratio: 5.28; 95% confidence interval: [3.67, 7.59]; p < 0.001) and predicted depression inception (odds ratio: 2.43; 95% confidence interval: [1.03-5.76]; p = 0.042) after controlling for important confounders. Mood instability did not predict maintenance of depression. Sleep difficulties and severe problems with close friends and family significantly mediated the link between mood instability and new onset depression (23.05% and 6.19% of the link, respectively). Alcohol abuse and divorce were not important mediators in the model. Mood instability is a precursor of a depressive episode, predicting its onset. Difficulties in sleep are a significant part of the pathway. Interventions targeting mood instability and sleep problems have the potential to reduce the risk of depression. © The Royal Australian and New Zealand College of Psychiatrists 2015.
Profiles of Observed Infant Anger Predict Preschool Behavior Problems: Moderation by Life Stress
ERIC Educational Resources Information Center
Brooker, Rebecca J.; Buss, Kristin A.; Lemery-Chalfant, Kathryn; Aksan, Nazan; Davidson, Richard J.; Goldsmith, H. Hill
2014-01-01
Using both traditional composites and novel profiles of anger, we examined associations between infant anger and preschool behavior problems in a large, longitudinal data set (N = 966). We also tested the role of life stress as a moderator of the link between early anger and the development of behavior problems. Although traditional measures of…
NASA Astrophysics Data System (ADS)
Daminelli, Simone; Thomas, Josephine Maria; Durán, Claudio; Vittorio Cannistraci, Carlo
2015-11-01
Bipartite networks are powerful descriptions of complex systems characterized by two different classes of nodes and connections allowed only across but not within the two classes. Unveiling physical principles, building theories and suggesting physical models to predict bipartite links such as product-consumer connections in recommendation systems or drug-target interactions in molecular networks can provide priceless information to improve e-commerce or to accelerate pharmaceutical research. The prediction of nonobserved connections starting from those already present in the topology of a network is known as the link-prediction problem. It represents an important subject both in many-body interaction theory in physics and in new algorithms for applied tools in computer science. The rationale is that the existing connectivity structure of a network can suggest where new connections can appear with higher likelihood in an evolving network, or where nonobserved connections are missing in a partially known network. Surprisingly, current complex network theory presents a theoretical bottle-neck: a general framework for local-based link prediction directly in the bipartite domain is missing. Here, we overcome this theoretical obstacle and present a formal definition of common neighbour index and local-community-paradigm (LCP) for bipartite networks. As a consequence, we are able to introduce the first node-neighbourhood-based and LCP-based models for topological link prediction that utilize the bipartite domain. We performed link prediction evaluations in several networks of different size and of disparate origin, including technological, social and biological systems. Our models significantly improve topological prediction in many bipartite networks because they exploit local physical driving-forces that participate in the formation and organization of many real-world bipartite networks. Furthermore, we present a local-based formalism that allows to intuitively implement neighbourhood-based link prediction entirely in the bipartite domain.
IJS: An Intelligent Junction Selection Based Routing Protocol for VANET to Support ITS Services.
Bhoi, Sourav Kumar; Khilar, Pabitra Mohan
2014-01-01
Selecting junctions intelligently for data transmission provides better intelligent transportation system (ITS) services. The main problem in vehicular communication is high disturbances of link connectivity due to mobility and less density of vehicles. If link conditions are predicted earlier, then there is a less chance of performance degradation. In this paper, an intelligent junction selection based routing protocol (IJS) is proposed to transmit the data in a quickest path, in which the vehicles are mostly connected and have less link connectivity problem. In this protocol, a helping vehicle is set at every junction to control the communication by predicting link failures or network gaps in a route. Helping vehicle at the junction produces a score for every neighboring junction to forward the data to the destination by considering the current traffic information and selects that junction which has minimum score. IJS protocol is implemented and compared with GyTAR, A-STAR, and GSR routing protocols. Simulation results show that IJS performs better in terms of average end-to-end delay, network gap encounter, and number of hops.
IJS: An Intelligent Junction Selection Based Routing Protocol for VANET to Support ITS Services
Khilar, Pabitra Mohan
2014-01-01
Selecting junctions intelligently for data transmission provides better intelligent transportation system (ITS) services. The main problem in vehicular communication is high disturbances of link connectivity due to mobility and less density of vehicles. If link conditions are predicted earlier, then there is a less chance of performance degradation. In this paper, an intelligent junction selection based routing protocol (IJS) is proposed to transmit the data in a quickest path, in which the vehicles are mostly connected and have less link connectivity problem. In this protocol, a helping vehicle is set at every junction to control the communication by predicting link failures or network gaps in a route. Helping vehicle at the junction produces a score for every neighboring junction to forward the data to the destination by considering the current traffic information and selects that junction which has minimum score. IJS protocol is implemented and compared with GyTAR, A-STAR, and GSR routing protocols. Simulation results show that IJS performs better in terms of average end-to-end delay, network gap encounter, and number of hops. PMID:27433485
Topic Models for Link Prediction in Document Networks
ERIC Educational Resources Information Center
Kataria, Saurabh
2012-01-01
Recent explosive growth of interconnected document collections such as citation networks, network of web pages, content generated by crowd-sourcing in collaborative environments, etc., has posed several challenging problems for data mining and machine learning community. One central problem in the domain of document networks is that of "link…
Boynton, Marcella H; O'Hara, Ross E; Covault, Jonathan; Scott, Denise; Tennen, Howard
2014-03-01
Racial discrimination has been identified as an important predictor of alcohol-related outcomes for African Americans. The goal of the current study was to extend previously found links between lifetime discrimination, alcohol use, and alcohol problems as well as to elucidate the affective mechanisms underlying these associations, as moderated by gender. A multiple-groups structural equation model was computed using survey data collected from 619 students from a historically Black college/university. The final model provided excellent fit to the data, explaining 6% of the variance in alcohol consumption and 37% of the variance in alcohol problems. Discrimination was a significant predictor of alcohol-related problems but not, by and large, level of use. For men, anger-but not discrimination-specific anger-was a significant partial mediator of the link between discrimination and both alcohol use and alcohol problems. Depression partially mediated the link between discrimination and alcohol problems for both men and women. The results suggest that, for African Americans whose drinking leads to drinking-related problems, discrimination and poor affective self-regulation are highly relevant and predictive factors, especially for men.
Conway, Anne; Miller, Alison L; Modrek, Anahid
2017-08-01
Sleep problems are associated with problematic adjustment in toddlers, but less is known regarding the direction of association between specific sleep problems and adjustment. To address this gap, we used data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development (N = 1001) to examine reciprocal associations between sleep problems and behavior problems from 24- to 36-months. Results from cross-lagged path models suggested specificity of associations between type of sleep problem and behavior problem. Specifically, there were reciprocal associations between trouble getting to sleep and internalizing problems, and unidirectional links between externalizing problems and bedtime resistance from 24- to 36-months. Internalizing and externalizing problems at 24 months, however, predicted increases in bedtime resistance from 24- to 36-months for boys, but not girls. Findings highlight specific relations between sleep problems and internalizing and externalizing problems during toddlerhood, and the importance of examining sex differences.
Marriage work in older couples: Disclosure of marital problems to spouses and friends over time.
Jensen, Jakob F; Rauer, Amy J
2015-10-01
This study examined the frequency and impact of "marriage work" (MW), or the act of discussing marital problems with spouses and friends, among a sample of older married couples (N = 64). Using actor-partner interdependence models, we examined how turning to one's spouse and one's friend was linked to changes in both spouses' marital satisfaction and conflict 1 year later. We also investigated whether satisfaction and conflict predicted change in MW for older spouses. Both wives and husbands engaged in more MW with spouses than with friends, and only husbands' MW with spouses decreased over time. Wives' MW with spouses was associated with decreased marital satisfaction for husbands, whereas husbands' MW with spouses was linked with increased satisfaction for husbands. Furthermore, wives' MW with spouses predicted increases in wives' marital conflict over time. When examining effects in the opposite direction, wives' marital satisfaction predicted decreases in wives' MW with spouse. Husbands' satisfaction was linked with increases in wives' MW with spouses, increases in wives' MW with friends, and decreases in husbands' MW with friends. Finally, husbands' conflict predicted increases in husbands' MW with friends. Findings suggest that openly engaging in discussions of marital problems may not be as uniformly helpful for aging couples as it is for their younger counterparts. Given that many older adults tend to actively avoid conflictual interactions in an attempt to maximize emotional rewards, researchers and clinicians should note that traditional approaches to working through romantic conflict may not be ideal for aging couples. (c) 2015 APA, all rights reserved).
Salzinger, Suzanne; Rosario, Margaret; Feldman, Richard S.; Ng-Mak, Daisy S.
2010-01-01
This study examines processes linking inner-city community violence exposure to subsequent internalizing and externalizing problems. Hypothesized risk and protective factors from three ecological domains -- children's parent and peer relationships and individual characteristics -- were examined for mediating, moderating or independent roles in predicting problem behavior among 667 children over three years of middle school. Mediation was not found. However, parent and peer variables moderated the association between exposure and internalizing problems. Under high exposure, normally protective factors (e.g., attachment to parents) were less effective in mitigating exposure's effects than under low exposure; attachment to friends was more effective. Individual competence was independently associated with decreased internalizing problems. Variables from all domains, and exposure, were independently associated with externalizing problems. Protective factors (e.g., parent attachment) predicted decreased problems; risk factors (e.g., friends' delinquency) predicted increased problems. Results indicate community violence reduction as essential in averting inner-city adolescents' poor behavioral outcomes. PMID:21643493
Bierman, Karen L.
2016-01-01
To investigate the differential emergence of antisocial behaviors and mood dysregulation among children with externalizing problems, the present study prospectively followed 317 high-risk children with early externalizing problems from school entry (ages 5–7) to late adolescence (ages 17–19). Latent class analysis conducted on their conduct and mood symptoms in late adolescence revealed three distinct patterns of symptoms, characterized by: 1) criminal offenses, conduct disorder symptoms, and elevated anger (“conduct problems”), 2) elevated anger, dysphoric mood, and suicidal ideation (“mood dysregulation”), and 3) low levels of severe conduct and mood symptoms. A diathesis-stress model predicting the first two outcomes was tested. Elevated overt aggression at school entry uniquely predicted conduct problems in late adolescence, whereas elevated emotion dysregulation at school entry uniquely predicted mood dysregulation in late adolescence. Experiences of low parental warmth and peer rejection in middle childhood moderated the link between early emotion dysregulation and later mood dysregulation but did not moderate the link between early overt aggression and later conduct problems. Thus, among children with early externalizing behavior problems, increased risk for later antisocial behavior or mood dysfunction may be identifiable in early childhood based on levels of overt aggression and emotion dysregulation. For children with early emotion dysregulation, however, increased risk for mood dysregulation characterized by anger, dysphoric mood, and suicidality – possibly indicative of disruptive mood dysregulation disorder – emerges only in the presence of low parental warmth and/or peer rejection during middle childhood. PMID:25183553
Academic Risk Among Inner-City Adolescents: The Role of Personal Attributes
Ripple, Carol H.; Luthar, Suniya S.
2012-01-01
In this 3-year prospective study, we explored antecedents of school-based adjustment among 134 inner-city high-school students. We examined the role of freshman-year risk and protective factors in relation to dropout status and senior-year adjustment indices among those who remained in school, including academic performance, psychological symptoms, and drug use. Although each single attribute included in this study has been linked to poor academic performance in previous investigations, the primary goal in this study was to determine which attributes were strongly related to academic problems when considered together. In addition, we sought to establish whether risk factors associated with dropout were the same as those that predicted academic problems among students who remained in school. Findings indicated that freshman-year attendance and demographic indices were most strongly predictive of dropout. Among adolescents who remained in school, freshman academic success was robustly linked to senior-year competence. Implications for identifying inner-city high-school students at high risk for academic problems are discussed. PMID:24839305
Frasquilho, Diana; de Matos, Margarida Gaspar; Marques, Adilson; Neville, Fergus G; Gaspar, Tânia; Caldas-de-Almeida, J M
2016-10-01
We investigated, in a sample of 112 unemployed parents of adolescents aged 10-19 years, the links between parental distress and change in youth emotional problems related to parental unemployment, and the moderation roles of parent-youth relationship and financial deprivation. Data were analyzed using descriptive statistics and correlations. Further, simple moderation, additive moderation, and moderated moderation models of regression were performed to analyze the effects of parental distress, parent-youth relationship and financial deprivation in predicting change in youth emotional problems related to parental unemployment. Results show that parental distress moderated by parent-youth relationship predicted levels of change in youth emotional problems related to parental unemployment. This study provides evidence that during job loss, parental distress is linked to youth emotional well-being and that parent-youth relationships play an important moderation role. This raises the importance of further researching parental distress impacts on youth well-being, especially during periods of high unemployment rates.
Lewis, Gary J; Asbury, Kathryn; Plomin, Robert
2017-03-01
Childhood behavior problems predict subsequent educational achievement; however, little research has examined the etiology of these links using a longitudinal twin design. Moreover, it is unknown whether genetic and environmental innovations provide incremental prediction for educational achievement from childhood to adolescence. We examined genetic and environmental influences on parental ratings of behavior problems across childhood (age 4) and adolescence (ages 12 and 16) as predictors of educational achievement at age 16 using a longitudinal classical twin design. Shared-environmental influences on anxiety, conduct problems, and peer problems at age 4 predicted educational achievement at age 16. Genetic influences on the externalizing behaviors of conduct problems and hyperactivity at age 4 predicted educational achievement at age 16. Moreover, novel genetic and (to a lesser extent) nonshared-environmental influences acting on conduct problems and hyperactivity emerged at ages 12 and 16, adding to the genetic prediction from age 4. These findings demonstrate that genetic and shared-environmental factors underpinning behavior problems in early childhood predict educational achievement in midadolescence. These findings are consistent with the notion that early-childhood behavior problems reflect the initiation of a life-course persistent trajectory with concomitant implications for social attainment. However, we also find evidence that genetic and nonshared-environment innovations acting on behavior problems have implications for subsequent educational achievement, consistent with recent work arguing that adolescence represents a sensitive period for socioaffective development. © 2016 The Authors. Journal of Child Psychology and Psychiatry published by John Wiley & Sons Ltd on behalf of Association for Child and Adolescent Mental Health.
Trumpower, David L; Goldsmith, Timothy E; Guynn, Melissa J
2004-12-01
Solving training problems with nonspecific goals (NG; i.e., solving for all possible unknown values) often results in better transfer than solving training problems with standard goals (SG; i.e., solving for one particular unknown value). In this study, we evaluated an attentional focus explanation of the goal specificity effect. According to the attentional focus view, solving NG problems causes attention to be directed to local relations among successive problem states, whereas solving SG problems causes attention to be directed to relations between the various problem states and the goal state. Attention to the former is thought to enhance structural knowledge about the problem domain and thus promote transfer. Results supported this view because structurally different transfer problems were solved faster following NG training than following SG training. Moreover, structural knowledge representations revealed more links depicting local relations following NG training and more links to the training goal following SG training. As predicted, these effects were obtained only by domain novices.
Influences of parent and child negative emotionality on young children's everyday behaviors.
Slatcher, Richard B; Trentacosta, Christopher J
2012-10-01
Negative emotionality is linked to unfavorable life outcomes, but studies have yet to examine negative emotionality of parents and children as predictors of children's problem behaviors and negative emotion word use in everyday life. This study used a novel naturalistic recording device called the Electronically Activated Recorder to investigate the separate and interactive influences of parent and child negative emotionality on daily child behaviors in a sample of 35 preschool-aged children over two time points separated by 1 year. Fathers' negative emotionality predicted children's whining at Time 1; mothers' negative emotionality predicted children's negative emotion word use at Time 1 and increases in children's arguing/fighting from Time 1 to Time 2. Parents' ratings of child negative emotionality also were associated with increases in children's arguing/fighting from Time 1 to Time 2, and child negative emotionality moderated the association between mothers' negative emotionality and children's arguing/fighting. Further, children with mothers high in negative emotionality displayed higher levels of problem behaviors when their mothers self-reported low levels of positive emotional expressiveness and/or high levels of negative emotional expressiveness. These findings offer preliminary evidence linking parent and child negative emotionality to everyday child behaviors and suggest that emotional expressiveness may play a key role in moderating the links between maternal negative emotionality and child behavioral problems.
Emery, Noah N; Simons, Jeffrey S
2017-08-01
This study tested a model linking sensitivity to punishment (SP) and reward (SR) to marijuana use and problems via affect lability and poor control. A 6-month prospective design was used in a sample of 2,270 young-adults (64% female). The hypothesized SP × SR interaction did not predict affect lability or poor control, but did predict use likelihood at baseline. At low levels of SR, SP was associated with an increased likelihood of abstaining, which was attenuated as SR increased. SP and SR displayed positive main effects on both affect lability and poor control. Affect lability and poor control, in turn, mediated effects on the marijuana outcomes. Poor control predicted both increased marijuana use and, controlling for use level, greater intensity of problems. Affect lability predicted greater intensity of problems, but was not associated with use level. There were few prospective effects. SR consistently predicted greater marijuana use and problems. SP however, exhibited both risk and protective pathways. Results indicate that SP is associated with a decreased likelihood of marijuana use. However, once use is initiated SP is associated with increased risk of problems, in part, due to its effects on both affect and behavioral dysregulation. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
ERIC Educational Resources Information Center
Mainert, Jakob; Kretzschmar, André; Neubert, Jonas C.; Greiff, Samuel
2015-01-01
Transversal skills, such as complex problem solving (CPS) are viewed as central twenty-first-century skills. Recent empirical findings have already supported the importance of CPS for early academic advancement. We wanted to determine whether CPS could also contribute to the understanding of career advancement later in life. Towards this end, we…
Blonigen, Daniel M; Timko, Christine; Moos, Bernice S; Moos, Rudolf H
2009-09-01
The link between impulsive personality traits and alcohol use disorders (AUDs) is well established. No studies, however, have investigated whether receipt of help for AUDs predicts change in impulsivity or whether such change is associated with relevant outcomes such as legal problems. The present study examined predictive associations between the duration of help for AUDs (Alcoholics Anonymous [AA], professional treatment) and impulsivity and legal problems over 16 years in men and women with AUDs. Participants who were initially untreated for their AUDs (n(men) = 332, n(women) = 296) completed follow-up telephone interviews at 1 and 16 years after their baseline assessment. Impulsivity and legal problems declined between baseline and the 1-year and 16-year follow-ups among both women and men. A longer duration of participation in AA predicted a decline in impulsivity at both follow-up assessments, and, in turn, a decline in impulsivity predicted a decline in legal problems at Years 1 and 16. In addition, a longer duration of participation in AA predicted fewer legal problems at Year 1, and this association was moderated by gender (significant in men) and impulsivity (significant for individuals with higher baseline scores). The results highlight the potential for AA and professional treatment to reduce the expression of impulsivity and related disinhibitory traits and legal problems in individuals with AUDs.
Performance of statistical models to predict mental health and substance abuse cost.
Montez-Rath, Maria; Christiansen, Cindy L; Ettner, Susan L; Loveland, Susan; Rosen, Amy K
2006-10-26
Providers use risk-adjustment systems to help manage healthcare costs. Typically, ordinary least squares (OLS) models on either untransformed or log-transformed cost are used. We examine the predictive ability of several statistical models, demonstrate how model choice depends on the goal for the predictive model, and examine whether building models on samples of the data affects model choice. Our sample consisted of 525,620 Veterans Health Administration patients with mental health (MH) or substance abuse (SA) diagnoses who incurred costs during fiscal year 1999. We tested two models on a transformation of cost: a Log Normal model and a Square-root Normal model, and three generalized linear models on untransformed cost, defined by distributional assumption and link function: Normal with identity link (OLS); Gamma with log link; and Gamma with square-root link. Risk-adjusters included age, sex, and 12 MH/SA categories. To determine the best model among the entire dataset, predictive ability was evaluated using root mean square error (RMSE), mean absolute prediction error (MAPE), and predictive ratios of predicted to observed cost (PR) among deciles of predicted cost, by comparing point estimates and 95% bias-corrected bootstrap confidence intervals. To study the effect of analyzing a random sample of the population on model choice, we re-computed these statistics using random samples beginning with 5,000 patients and ending with the entire sample. The Square-root Normal model had the lowest estimates of the RMSE and MAPE, with bootstrap confidence intervals that were always lower than those for the other models. The Gamma with square-root link was best as measured by the PRs. The choice of best model could vary if smaller samples were used and the Gamma with square-root link model had convergence problems with small samples. Models with square-root transformation or link fit the data best. This function (whether used as transformation or as a link) seems to help deal with the high comorbidity of this population by introducing a form of interaction. The Gamma distribution helps with the long tail of the distribution. However, the Normal distribution is suitable if the correct transformation of the outcome is used.
Profiles of observed infant anger predict preschool behavior problems: Moderation by life stress
Brooker, Rebecca J.; Buss, Kristin A.; Lemery-Chalfant, Kathryn; Aksan, Nazan; Davidson, Richard J.; Goldsmith, H. Hill
2014-01-01
Using both traditional composites and novel profiles of anger, we examined associations between infant anger and preschool behavior problems in a large, longitudinal data set (N = 966). We also tested the role of life stress as a moderator of the link between early anger and the development of behavior problems. Although traditional measures of anger were largely unrelated to later behavior problems, profiles of anger that dissociated typical from atypical development predicted behavior problems during preschool. Moreover, the relation between infant anger profiles and preschool behavior problems was moderated such that, when early life stress was low, infants with atypical profiles of early anger showed more preschool behavior problems than did infants with normative anger profiles. However, when early life stress was high, infants with atypical and normative profiles of infant anger did not differ in preschool behavior problems. We conclude that a discrete emotions approach including latent profile analysis is useful for elucidating biological and environmental developmental pathways to early problem behaviors. PMID:25151247
Padilla-Walker, Laura M; Carlo, Gustavo; Nielson, Matthew G
2015-01-01
The current study examined bidirectional, longitudinal links between prosocial and problem behavior. Participants (N = 500) were recruited from a Northwestern city in the United States and assessed for 3 consecutive years from 2009 to 2011 (M(age) of youth at Time 1 = 13.32, SD = 1.05; 52% girls; 67% European American, 33% single-parent families). Results suggested that effects of earlier prosocial behavior toward family and strangers were predictive of fewer problem behaviors 2 years later, while results for prosocial behavior toward friends were more mixed. Results also suggested depression predicted lower prosocial behavior toward family members and anxiety predicted higher prosocial behavior toward friends. Findings show a complex pattern of relations that demonstrate the need to consider targets of helping. © 2015 The Authors. Child Development © 2015 Society for Research in Child Development, Inc.
Koblinsky, Sally A; Kuvalanka, Katherine A; Randolph, Suzanne M
2006-10-01
This study examined the role of parenting, family routines, family conflict, and maternal depression in predicting the social skills and behavior problems of low-income African American preschoolers. A sample of 184 African American mothers of Head Start children completed participant and child measures in a structured interview. Results of regression analyses revealed that mothers who utilized more positive parenting practices and engaged in more family routines had children who displayed higher levels of total prosocial skills. Positive parenting and lower levels of maternal depressive symptoms were predictive of fewer externalizing and internalizing child behavior problems. Lower family conflict was linked with fewer externalizing problems. Implications of the study for future research and intervention are discussed. (c) 2007 APA, all rights reserved
Wang, Ming-Te; Kenny, Sarah
2013-01-01
This study used cross-lagged modeling to examine reciprocal relations between maternal and paternal harsh verbal discipline and adolescents' conduct problems and depressive symptoms. Data were from a sample of 976 two-parent families and their children (51% males; 54% European American, 40% African American). Mothers' and fathers' harsh verbal discipline at age 13 predicted an increase in adolescent conduct problems and depressive symptoms between ages 13 and 14. A child effect was also present, with adolescent misconduct at age 13 predicting increases in mothers' and fathers' harsh verbal discipline between ages 13 and 14. Furthermore, maternal and paternal warmth did not moderate the longitudinal associations between mothers' and fathers' use of harsh verbal discipline and adolescent conduct problems and depressive symptoms. PMID:24001259
Thompson, Charee M; Romo, Lynsey K
2016-06-01
College drinking continues to remain a public health problem that has been exacerbated by alcohol-related posts on social networking sites (SNSs). Although existing research has linked alcohol consumption, alcohol posts, and adverse consequences to one another, comprehensive explanations for these associations have been largely unexplored. Thus, we reasoned that students' personal motivations (i.e., espousing an alcohol identity, needing entertainment, and adhering to social norms) influence their behaviors (i.e., alcohol consumption and alcohol-related posting on SNSs), which can lead to alcohol problems. Using structural equation modeling, we analyzed data from 364 undergraduate students and found general support for our model. In particular, espousing an alcohol identity predicted alcohol consumption and alcohol-related SNS posting, needing entertainment predicted alcohol consumption but not alcohol-related SNS posting, and adhering to social norms predicted alcohol-related SNS posting but not alcohol consumption. In turn, alcohol consumption and alcohol-related SNS posting predicted alcohol problems. It is surprising that alcohol-related SNS posting was a stronger predictor of alcohol problems than alcohol consumption. We discuss the findings within their applied applications for college student health.
Predicting the distribution of bed material accumulation using river network sediment budgets
NASA Astrophysics Data System (ADS)
Wilkinson, Scott N.; Prosser, Ian P.; Hughes, Andrew O.
2006-10-01
Assessing the spatial distribution of bed material accumulation in river networks is important for determining the impacts of erosion on downstream channel form and habitat and for planning erosion and sediment management. A model that constructs spatially distributed budgets of bed material sediment is developed to predict the locations of accumulation following land use change. For each link in the river network, GIS algorithms are used to predict bed material supply from gullies, river banks, and upstream tributaries and to compare total supply with transport capacity. The model is tested in the 29,000 km2 Murrumbidgee River catchment in southeast Australia. It correctly predicts the presence or absence of accumulation in 71% of river links, which is significantly better performance than previous models, which do not account for spatial variability in sediment supply and transport capacity. Representing transient sediment storage is important for predicting smaller accumulations. Bed material accumulation is predicted in 25% of the river network, indicating its importance as an environmental problem in Australia.
Influences of Parent and Child Negative Emotionality on Young Children’s Everyday Behaviors
Slatcher, Richard B.; Trentacosta, Christopher J.
2012-01-01
Negative emotionality is linked to unfavorable life outcomes, but studies have yet to examine negative emotionality of parents and children as predictors of children’s problem behaviors and negative emotion word use in everyday life. This study used a novel naturalistic recording device called the Electronically Activated Recorder (EAR) to investigate the separate and interactive influences of parent and child negative emotionality on daily child behaviors in a sample of 35 preschool-aged children over two time points separated by one year. Fathers’ negative emotionality predicted children’s whining at Time 1; mothers’ negative emotionality predicted children’s negative emotion word use at Time 1 and increases in children’s arguing/fighting from Time 1 to Time 2. Parents’ ratings of child negative emotionality also were associated with increases in children’s arguing/fighting from Time 1 to Time 2, and child negative emotionality moderated the association between mothers’ negative emotionality and children’s arguing/fighting. Further, children with mothers high in negative emotionality displayed higher levels of problem behaviors when their mothers self-reported low levels of positive emotional expressiveness and/or high levels of negative emotional expressiveness. These findings offer preliminary evidence linking parent and child negative emotionality to everyday child behaviors, and suggest that emotional expressiveness may play a key role in moderating the links between maternal negative emotionality and child behavioral problems. PMID:22390707
Lipscomb, Shannon T; Leve, Leslie D; Shaw, Daniel S; Neiderhiser, Jenae M; Scaramella, Laura V; Ge, Xiaojia; Conger, Rand D; Reid, John B; Reiss, David
2012-02-01
The current study examines the interplay between parental overreactivity and children's genetic backgrounds as inferred from birth parent characteristics on the development of negative emotionality during infancy, and in turn, to individual differences in externalizing problems in toddlerhood. The sample included 361 families linked through adoption (birth parents and adoptive families). Data were collected when the children were 9, 18, and 27 months old. Results indicated links between individual levels and changes in negative emotionality during infancy and toddlerhood to externalizing problems early in the third year of life. Findings also revealed an interaction between birth mother negative affect and adoptive mother overreactive parenting on children's negative emotionality. This Genotype × Environment interaction predicted externalizing problems indirectly through its association with negative emotionality and revealed stronger effects of genetic risk for children with less overreactive parenting from their mothers. Limitations of this study and directions for future research are discussed.
Waller, Rebecca; Dishion, Thomas J.; Shaw, Daniel S.; Gardner, Frances; Wilson, Melvin N.; Hyde, Luke W.
2016-01-01
Callous unemotional (CU) behavior has been linked to behavior problems in children and adolescents. However, few studies have examined whether CU behavior in early childhood predicts behavior problems or CU behavior in late childhood. This study examined whether indicators of CU behavior at ages 2–4 predicted aggression, rule-breaking, and CU behavior across informants at age 9.5. To test the unique predictive and convergent validity of CU behavior in early childhood, we accounted for stability in behavior problems and method effects to rule out the possibility that rater biases inflated the magnitude of any associations found. Cross-informant data were collected from a multi-ethnic, high-risk sample (N = 731; female = 49%) at ages 2–4 and again at age 9.5. From age 3, CU behavior uniquely predicted aggression and rule-breaking across informants. There were also unique associations between CU behavior assessed at ages 3 and 4 and CU behavior assessed at age 9.5. Findings demonstrate that early-childhood indicators of CU behavior account for unique variance in later childhood behavior problems and CU behavior, taking into account stability in behavior problems over time and method effects. Convergence with a traditional measure of CU behavior in late childhood provides support for the construct validity of a brief early childhood measure of CU behavior. PMID:27598253
Wang, Ming-Te; Fredricks, Jennifer
2013-01-01
Drawing on the self-system model, this study conceptualized school engagement as a multidimensional construct, including behavioral, emotional, and cognitive engagement, and examined whether changes in the three types of school engagement related to changes in problem behaviors from 7th through 11th grade. In addition, a transactional model of reciprocal relations between school engagement and problem behaviors was tested to predict school dropout. Data were collected on 1,272 youth from an ethnically and economically diverse county (58% African American, 36% European American; 51% females). Results indicated that adolescents who had declines in behavioral and emotional engagement with school tended to engage in increased delinquency and substance use over time. There were bidirectional associations between behavioral and emotional engagement in school and youth problem behaviors over time. Finally, lower behavioral and emotional engagement and greater problem behaviors predicted greater likelihood of dropping out of school. PMID:23895361
Morgan, Judith K.; Izard, Carroll E.; Hyde, Christopher
2013-01-01
Children’s emotional reactivity may interact with their regulatory behaviors to contribute to internalizing problems and social functioning even early in development. Ninety-one preschool children participated in a longitudinal project examining children’s reactivity and regulatory behaviors as predictors of internalizing problems and positive and negative social behavior in the classroom. Children who paired negative emotion expression with disengagement during a laboratory task showed higher levels of internalizing problems and more negative social behavior in the classroom six months later. Positive emotion expression paired with engagement during a laboratory task predicted more positive social behavior in the classroom six months later. Physiological reactivity and regulation also predicted children’s social behavior in the classroom. Findings suggest that preschool children with maladaptive reactivity and regulatory patterns may be at greater risk for internalizing problems even in early childhood. PMID:25067866
Lansford, Jennifer E.; Laird, Robert D.; Pettit, Gregory S.; Bates, John E.; Dodge, Kenneth A.
2014-01-01
The goal of this study was to advance the understanding of separate and joint effects of mothers’ and fathers’ autonomy-relevant parenting during early and middle adolescence. In a sample of 518 families, adolescents (49% female; 83% European American, 16% African American, 1% other ethnic groups) reported on their mothers’ and fathers’ psychological control and knowledge about adolescents’ whereabouts, friends, and activities at ages 13 and 16. Mothers and adolescents reported on adolescents’ externalizing and internalizing behaviors at ages 12, 14, 15, and 17. Adolescents perceived their mothers as using more psychological control and having more knowledge than their fathers, but there was moderate concordance between adolescents’ perceptions of their mothers and fathers. More parental psychological control predicted increases in boys’ and girls’ internalizing problems and girls’ externalizing problems. More parental knowledge predicted decreases in boys’ externalizing and internalizing problems. The perceived levels of behavior of mothers and fathers did not interact with one another in predicting adolescent adjustment. The results generalize across early and late adolescence and across mothers’ and adolescents’ reports of behavior problems. Autonomy-relevant mothering and fathering predict changes in behavior problems during early and late adolescence, but only autonomy-relevant fathering accounts for unique variance in adolescent behavior problems. PMID:24337705
Lansford, Jennifer E; Laird, Robert D; Pettit, Gregory S; Bates, John E; Dodge, Kenneth A
2014-11-01
The goal of this study was to advance the understanding of separate and joint effects of mothers' and fathers' autonomy-relevant parenting during early and middle adolescence. In a sample of 518 families, adolescents (49 % female; 83 % European American, 16 % African American, 1 % other ethnic groups) reported on their mothers' and fathers' psychological control and knowledge about adolescents' whereabouts, friends, and activities at ages 13 and 16. Mothers and adolescents reported on adolescents' externalizing and internalizing behaviors at ages 12, 14, 15, and 17. Adolescents perceived their mothers as using more psychological control and having more knowledge than their fathers, but there was moderate concordance between adolescents' perceptions of their mothers and fathers. More parental psychological control predicted increases in boys' and girls' internalizing problems and girls' externalizing problems. More parental knowledge predicted decreases in boys' externalizing and internalizing problems. The perceived levels of behavior of mothers and fathers did not interact with one another in predicting adolescent adjustment. The results generalize across early and late adolescence and across mothers' and adolescents' reports of behavior problems. Autonomy-relevant mothering and fathering predict changes in behavior problems during early and late adolescence, but only autonomy-relevant fathering accounts for unique variance in adolescent behavior problems.
Longitudinal predictors of high school completion.
Barry, Melissa; Reschly, Amy L
2012-06-01
This longitudinal study examined predictors of dropout assessed in elementary school. Student demographic data, achievement, attendance, and ratings of behavior from the Behavior Assessment System for Children were used to predict dropout and completion. Two models, which varied on student sex and race, predicted dropout at rates ranging from 75% to 88%. Model A, which included the Behavioral Symptoms Index, School Problems composite, Iowa Tests of Basic Skills battery, and teacher ratings of student work habits, best predicted female and African American dropouts. Model B, which comprised the Adaptive Skills composite, the Externalizing composite, the School Problems composite, referral for a student support team meeting, and sex, was more accurate for predicting Caucasian dropouts. Both models demonstrated the same hit rates for predicting male dropouts. Recommendations for early warning indicators and linking predictors with interventions are discussed. (PsycINFO Database Record (c) 2012 APA, all rights reserved).
Dishion, Thomas J.; Ha, Thao; Véronneau, Marie-Hélène
2012-01-01
This study proposes the inclusion of peer relationships in a life history perspective on adolescent problem behavior. Longitudinal analyses were used to examine deviant peer clustering as the mediating link between attenuated family ties, peer marginalization, and social disadvantage in early adolescence and sexual promiscuity in middle adolescence and childbearing by early adulthood. Specifically, 998 youth and their families were assessed at age 11 years and periodically through age 24 years. Structural equation modeling revealed that the peer-enhanced life history model provided a good fit to the longitudinal data, with deviant peer clustering strongly predicting adolescent sexual promiscuity and other correlated problem behaviors. Sexual promiscuity, as expected, also strongly predicted the number of children by age 22–24 years. Consistent with a life history perspective, family social disadvantage directly predicted deviant peer clustering and number of children in early adulthood, controlling for all other variables in the model. These data suggest that deviant peer clustering is a core dimension of a fast life history strategy, with strong links to sexual activity and childbearing. The implications of these findings are discussed with respect to the need to integrate an evolutionary-based model of self-organized peer groups in developmental and intervention science. PMID:22409765
Dishion, Thomas J; Ha, Thao; Véronneau, Marie-Hélène
2012-05-01
The authors propose that peer relationships should be included in a life history perspective on adolescent problem behavior. Longitudinal analyses were used to examine deviant peer clustering as the mediating link between attenuated family ties, peer marginalization, and social disadvantage in early adolescence and sexual promiscuity in middle adolescence and childbearing by early adulthood. Specifically, 998 youths, along with their families, were assessed at age 11 years and periodically through age 24 years. Structural equation modeling revealed that the peer-enhanced life history model provided a good fit to the longitudinal data, with deviant peer clustering strongly predicting adolescent sexual promiscuity and other correlated problem behaviors. Sexual promiscuity, as expected, also strongly predicted the number of children by ages 22-24 years. Consistent with a life history perspective, family social disadvantage directly predicted deviant peer clustering and number of children in early adulthood, controlling for all other variables in the model. These data suggest that deviant peer clustering is a core dimension of a fast life history strategy, with strong links to sexual activity and childbearing. The implications of these findings are discussed with respect to the need to integrate an evolutionary-based model of self-organized peer groups in developmental and intervention science.
Consumer Information Use: Individual Versus Social Predictors.
ERIC Educational Resources Information Center
Moschis, George P.
1980-01-01
Presents a study which attempts to link current theory to practical problems of applied communication. The power of coorientational variables is tested and compared with the power of commonly used individual characteristics in predicting the amounts and types of information sought by buyers of cosmetics. (JMF)
Array Simulations Platform (ASP) predicts NASA Data Link Module (NDLM) performance
NASA Technical Reports Server (NTRS)
Snook, Allen David
1993-01-01
Through a variety of imbedded theoretical and actual antenna patterns, the array simulation platform (ASP) enhanced analysis of the array antenna pattern effects for the KTx (Ku-Band Transmit) service of the NDLM (NASA Data Link Module). The ASP utilizes internally stored models of the NDLM antennas and can develop the overall pattern of antenna arrays through common array calculation techniques. ASP expertly assisted in the diagnosing of element phase shifter errors during KTx testing and was able to accurately predict the overall array pattern from combinations of the four internally held element patterns. This paper provides an overview of the use of the ASP software in the solving of array mis-phasing problems.
Morgan, Judith K; Shaw, Daniel S; Olino, Thomas M
2012-08-01
Whereas socialization influences in early childhood have been linked to children's emerging internalizing problems and prosocial behavior, relatively few studies have examined how NE might moderate such associations in both advantageous and maladaptive ways. Furthermore, more research is needed to evaluate the impact of sibling relationships as an influential socialization influence on these child outcomes. In the current study we examined how NE might differentially moderate the associations between quality of relationships with siblings and both internalizing problems and social skills at school entry. NE moderated the effects of positive and destructive sibling relationship quality on child internalizing problems. Specifically, for boys high on NE, more positive sibling relationship quality predicted fewer internalizing problems, but more destructive sibling conflict predicted more internalizing problems. NE also moderated the effects of destructive sibling conflict on child social skills. For boys high on NE, destructive sibling conflict predicted fewer social skills. Boys high on NE appear to show greater susceptibility to the effects of sibling socialization on child outcomes, relative to boys low on NE. The implications of these interactions are discussed with respect to differential susceptibility theory.
Shaw, Daniel S.; Olino, Thomas M.
2012-01-01
Whereas socialization influences in early childhood have been linked to children’s emerging internalizing problems and prosocial behavior, relatively few studies have examined how NE might moderate such associations in both advantageous and maladaptive ways. Furthermore, more research is needed to evaluate the impact of sibling relationships as an influential socialization influence on these child outcomes. In the current study we examined how NE might differentially moderate the associations between quality of relationships with siblings and both internalizing problems and social skills at school entry. NE moderated the effects of positive and destructive sibling relationship quality on child internalizing problems. Specifically, for boys high on NE, more positive sibling relationship quality predicted fewer internalizing problems, but more destructive sibling conflict predicted more internalizing problems. NE also moderated the effects of destructive sibling conflict on child social skills. For boys high on NE, destructive sibling conflict predicted fewer social skills. Boys high on NE appear to show greater susceptibility to the effects of sibling socialization on child outcomes, relative to boys low on NE. The implications of these interactions are discussed with respect to differential susceptibility theory. PMID:22366882
Claessens, Amy; Dowsett, Chantelle
2014-12-01
Despite widespread interest in children's adjustment problems, existing research does not provide conclusive evidence regarding the direction of the associations of achievement with classroom attention problems and disruptive behavior over the course of elementary school. Using a nationally representative sample of 16,260 kindergarteners, this study examined the temporal sequence of achievement, classroom attention problems, and disruptive behavior, focusing on how changes in skills and problems unfold across key periods between kindergarten and fifth grade. Results indicate that improvements in attention during the earliest years of schooling predict achievement gains through third grade. However, changes in disruptive behavior do not predict subsequent changes in achievement. Evidence linking changes in achievement to changes in classroom attention problems and disruptive behavior was less consistent. These findings point to the need to develop and examine early interventions that can improve attention skills as a mechanism for improving children's academic trajectories in elementary school. © The Author(s) 2014.
Lee, Dong-Gwi; Park, Hyun-Joo; Heppner, Mary J
2009-12-01
Using Heppner, et al.'s data from 2004, this study tested career counseling clients in the United States on problem-solving appraisal scores and career-related variables. A cross-lagged panel design with structural equation modeling was used. Results supported the link between clients' precounseling problem-solving appraisal scores and career outcome. This finding held for career decision-making, but not for vocational identity. The study provided further support for Heppner, et al.'s findings, highlighting the influential role of clients' problem-solving appraisals in advancing their career decision-making processes.
Fortin, Guillaume; Lecomte, Tania; Corbière, Marc
2017-06-01
When employment difficulties in people with severe mental illness (SMI) occur, it could be partly linked to issues not specific to SMI, such as personality traits or problems. Despite the fact that personality has a marked influence on almost every aspect of work behavior, it has scarcely been investigated in the context of employment for people with SMI. We aimed to evaluate if personality was more predictive than clinical variables of different competitive work outcomes, namely acquisition of competitive employment, delay to acquisition and job tenure. A sample of 82 people with a SMI enrolled in supported employment programs (SEP) was recruited and asked to complete various questionnaires and interviews. Statistical analyses included logistic regressions and survival analyses (Cox regressions). Prior employment, personality problems and negative symptoms are significantly related to acquisition of a competitive employment and to delay to acquisition whereas the conscientiousness personality trait was predictive of job tenure. Our results point out the relevance of personality traits and problems as predictors of work outcomes in people with SMI registered in SEP. Future studies should recruit larger samples and also investigate these links with other factors related to work outcomes.
Clements, Mari L.; Martin, Sarah E.; Randall, David W.; Kane, Karen L.
2014-01-01
Interparental relationship conflict has consistently been linked to child adjustment problems, with children’s perceptions of such conflict particularly predictive of their outcomes. Despite mounting evidence that preschool children can provide reliable and valid accounts of family functioning, little research has examined preschool children’s perceptions of interparental conflict. The present study employed a multi-informant design for both reports of interparental conflict (preschool children and their mothers and fathers) and reports of child adjustment (preschool children, their mothers and fathers, and their preschool teachers). Children completed pictorial measures of interparental conflict and of self-esteem that paralleled questionnaires completed by adult respondents. For both child behavior problems and child self-esteem, preschool children’s perceptions of interparental conflict predicted their adjustment. Preschool children’s reports of interparental conflict were significantly associated with their self-esteem and with both parents’ and teachers’ reports of child behavior problems, and this association remained significant when controlling for parents’ reports of interparental conflict. Further, the interaction between parents’ reports and children’s reports of interparental conflict added unique variance to the prediction of preschool teachers’ reports of children’s behavior problems. PMID:25574451
Leeuwis, Franca H; Koot, Hans M; Creemers, Daan H M; van Lier, Pol A C
2015-07-01
Discrepancies between implicit and explicit self-esteem have been linked with internalizing problems among mainly adolescents and adults. Longitudinal research on this association in children is lacking. This study examined the longitudinal link between self-esteem discrepancies and the development of internalizing problems in children. It furthermore examined the possible mediating role of self-esteem discrepancies in the longitudinal link between experiences of peer victimization and internalizing problems development. Children (N = 330, M(age) = 11.2 year; 52.5 % female) were followed over grades five (age 11 years) and six (age 12 years). Self-report measures were used annually to test for victimization and internalizing problems. Implicit self-esteem was assessed using an implicit association test, while explicit self-esteem was assessed via self-reports. Self-esteem discrepancies represented the difference between implicit and explicit self-esteem. Results showed that victimization was associated with increases in damaged self-esteem (higher levels of implicit than explicit self-esteem. Additionally, damaged self-esteem at age 11 years predicted an increase in internalizing problems in children over ages 11 to 12 years. Furthermore, damaged self-esteem mediated the relationship between age 11 years victimization and the development of internalizing problems. No impact of fragile self-esteem (lower levels of implicit than explicit self-esteem) on internalizing problems was found. The results thus underscore that, as found in adolescent and adult samples, damaged self-esteem is a predictor of increases in childhood internalizing problems. Moreover, damaged self-esteem might explain why children who are victimized develop internalizing problems. Implications are discussed.
Predictive factors of excessive online poker playing.
Hopley, Anthony A B; Nicki, Richard M
2010-08-01
Despite the widespread rise of online poker playing, there is a paucity of research examining potential predictors for excessive poker playing. The aim of this study was to build on recent research examining motives for Texas Hold'em play in students by determining whether predictors of other kinds of excessive gambling apply to Texas Hold'em. Impulsivity, negative mood states, dissociation, and boredom proneness have been linked to general problem gambling and may play a role in online poker. Participants of this study were self-selected online poker players (N = 179) who completed an online survey. Results revealed that participants played an average of 20 hours of online poker a week and approximately 9% of the sample was classified as a problem gambler according to the Canadian Problem Gambling Index. Problem gambling, in this sample, was uniquely predicted by time played, dissociation, boredom proneness, impulsivity, and negative affective states, namely depression, anxiety, and stress.
Wang, Ming-Te; Kenny, Sarah
2014-01-01
This study used cross-lagged modeling to examine reciprocal relations between maternal and paternal harsh verbal discipline and adolescents' conduct problems and depressive symptoms. Data were from a sample of 976 two-parent families and their children (51% males; 54% European American, 40% African American). Mothers' and fathers' harsh verbal discipline at age 13 predicted an increase in adolescent conduct problems and depressive symptoms between ages 13 and 14. A child effect was also present, with adolescent misconduct at age 13 predicting increases in mothers' and fathers' harsh verbal discipline between ages 13 and 14. Furthermore, maternal and paternal warmth did not moderate the longitudinal associations between mothers' and fathers' use of harsh verbal discipline and adolescent conduct problems and depressive symptoms. © 2013 The Authors. Child Development © 2013 Society for Research in Child Development, Inc.
Fong, Michelle C; Measelle, Jeffrey; Conradt, Elisabeth; Ablow, Jennifer C
2017-02-01
The purpose of the current study was to predict concurrent levels of problem behaviors from young children's baseline cortisol and attachment classification, a proxy for the quality of caregiving experienced. In a sample of 58 children living at or below the federal poverty threshold, children's baseline cortisol levels, attachment classification, and problem behaviors were assessed at 17 months of age. We hypothesized that an interaction between baseline cortisol and attachment classification would predict problem behaviors above and beyond any main effects of baseline cortisol and attachment. However, based on limited prior research, we did not predict whether or not this interaction would be more consistent with diathesis-stress or differential susceptibility models. Consistent with diathesis-stress theory, the results indicated no significant differences in problem behavior levels among children with high baseline cortisol. In contrast, children with low baseline cortisol had the highest level of problem behaviors in the context of a disorganized attachment relationship. However, in the context of a secure attachment relationship, children with low baseline cortisol looked no different, with respect to problem behavior levels, then children with high cortisol levels. These findings have substantive implications for the socioemotional development of children reared in poverty. Copyright © 2017 Elsevier Inc. All rights reserved.
Purpura, David J; Hume, Laura E; Sims, Darcey M; Lonigan, Christopher J
2011-12-01
The purpose of this study was to examine whether early literacy skills uniquely predict early numeracy skills development. During the first year of the study, 69 3- to 5-year-old preschoolers were assessed on the Preschool Early Numeracy Skills (PENS) test and the Test of Preschool Early Literacy Skills (TOPEL). Participants were assessed again a year later on the PENS test and on the Applied Problems and Calculation subtests of the Woodcock-Johnson III Tests of Achievement. Three mixed effect regressions were conducted using Time 2 PENS, Applied Problems, and Calculation as the dependent variables. Print Knowledge and Vocabulary accounted for unique variance in the prediction of Time 2 numeracy scores. Phonological Awareness did not uniquely predict any of the mathematics domains. The findings of this study identify an important link between early literacy and early numeracy development. Copyright © 2011 Elsevier Inc. All rights reserved.
Trim, Ryan S.; Schuckit, Marc A.; Smith, Tom L.
2009-01-01
Previous research has shown that an early onset of drinking is associated with a range of problematic drinking outcomes in adulthood. However, earlier drinking is also linked to additional characteristics that themselves predict alcohol problems including male gender, a family history (FH) of alcoholism, age, race, parental alcoholism, depression symptoms, prior drug use, and conduct problems. This study tested the relationship between the age of first drink (AFD) and a range of risk factors that predict the onset of alcohol use. Participants were offspring from the San Diego Prospective Study (SDPS) who were at least 15 years old at the time of their most recent interview (n=147). Discrete-time survival analysis (DTSA) was used to relate multiple characteristics to the hazard function of alcohol onset across a relevant age range. The results demonstrated the predicted relationships to AFD for conduct problems, male gender, prior marijuana use, and a FH of alcoholism, even when these characteristics were estimated together. Furthermore, an interaction occurred such that offspring with both conduct problems and marijuana use were at substantially higher risk for alcohol use onset during this time period than would be predicted from the effect of these two risk factors alone. However, age at interview, ethnicity, parent education, and depressive symptoms did not predict the pattern of onset of drinking. Implications for future research and prevention efforts are discussed. PMID:19959300
Groundwater Pollution Source Identification using Linked ANN-Optimization Model
NASA Astrophysics Data System (ADS)
Ayaz, Md; Srivastava, Rajesh; Jain, Ashu
2014-05-01
Groundwater is the principal source of drinking water in several parts of the world. Contamination of groundwater has become a serious health and environmental problem today. Human activities including industrial and agricultural activities are generally responsible for this contamination. Identification of groundwater pollution source is a major step in groundwater pollution remediation. Complete knowledge of pollution source in terms of its source characteristics is essential to adopt an effective remediation strategy. Groundwater pollution source is said to be identified completely when the source characteristics - location, strength and release period - are known. Identification of unknown groundwater pollution source is an ill-posed inverse problem. It becomes more difficult for real field conditions, when the lag time between the first reading at observation well and the time at which the source becomes active is not known. We developed a linked ANN-Optimization model for complete identification of an unknown groundwater pollution source. The model comprises two parts- an optimization model and an ANN model. Decision variables of linked ANN-Optimization model contain source location and release period of pollution source. An objective function is formulated using the spatial and temporal data of observed and simulated concentrations, and then minimized to identify the pollution source parameters. In the formulation of the objective function, we require the lag time which is not known. An ANN model with one hidden layer is trained using Levenberg-Marquardt algorithm to find the lag time. Different combinations of source locations and release periods are used as inputs and lag time is obtained as the output. Performance of the proposed model is evaluated for two and three dimensional case with error-free and erroneous data. Erroneous data was generated by adding uniformly distributed random error (error level 0-10%) to the analytically computed concentration values. The main advantage of the proposed model is that it requires only upper half of the breakthrough curve and is capable of predicting source parameters when the lag time is not known. Linking of ANN model with proposed optimization model reduces the dimensionality of the decision variables of the optimization model by one and hence complexity of optimization model is reduced. The results show that our proposed linked ANN-Optimization model is able to predict the source parameters for the error-free data accurately. The proposed model was run several times to obtain the mean, standard deviation and interval estimate of the predicted parameters for observations with random measurement errors. It was observed that mean values as predicted by the model were quite close to the exact values. An increasing trend was observed in the standard deviation of the predicted values with increasing level of measurement error. The model appears to be robust and may be efficiently utilized to solve the inverse pollution source identification problem.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hansen, Scott; Haslauer, Claus P.; Cirpka, Olaf A.
2017-01-05
The key points of this presentation were to approach the problem of linking breakthrough curve shape (RP-CTRW transition distribution) to structural parameters from a Monte Carlo approach and to use the Monte Carlo analysis to determine any empirical error
Working memory and organizational skills problems in ADHD.
Kofler, Michael J; Sarver, Dustin E; Harmon, Sherelle L; Moltisanti, Allison; Aduen, Paula A; Soto, Elia F; Ferretti, Nicole
2018-01-01
This study tested model-driven predictions regarding working memory's role in the organizational problems associated with ADHD. Children aged 8-13 (M = 10.33, SD = 1.42) with and without ADHD (N = 103; 39 girls; 73% Caucasian/Non-Hispanic) were assessed on multiple, counterbalanced working memory tasks. Parents and teachers completed norm-referenced measures of organizational problems (Children's Organizational Skills Scale; COSS). Results confirmed large magnitude working memory deficits (d = 1.24) and organizational problems in ADHD (d = 0.85). Bias-corrected, bootstrapped conditional effects models linked impaired working memory with greater parent- and teacher-reported inattention, hyperactivity/impulsivity, and organizational problems. Working memory predicted organization problems across all parent and teacher COSS subscales (R 2 = .19-.23). Approximately 38%-57% of working memory's effect on organization problems was conveyed by working memory's association with inattentive behavior. Unique effects of working memory remained significant for both parent- and teacher-reported task planning, as well as for teacher-reported memory/materials management and overall organization problems. Attention problems uniquely predicted worse organizational skills. Hyperactivity was unrelated to parent-reported organizational skills, but predicted better teacher-reported task planning. Children with ADHD exhibit multisetting, broad-based organizational impairment. These impaired organizational skills are attributable in part to performance deficits secondary to working memory dysfunction, both directly and indirectly via working memory's role in regulating attention. Impaired working memory in ADHD renders it extraordinarily difficult for these children to consistently anticipate, plan, enact, and maintain goal-directed actions. © 2017 Association for Child and Adolescent Mental Health.
Brooker, Rebecca J.; Buss, Kristin A.
2014-01-01
Temperamentally fearful children are at increased risk for the development of anxiety problems relative to less-fearful children. This risk is even greater when early environments include high levels of harsh parenting behaviors. However, the mechanisms by which harsh parenting may impact fearful children’s risk for anxiety problems are largely unknown. Recent neuroscience work has suggested that punishment is associated with exaggerated error-related negativity (ERN), an event-related potential linked to performance monitoring, even after the threat of punishment is removed. In the current study, we examined the possibility that harsh parenting interacts with fearfulness, impacting anxiety risk via neural processes of performance monitoring. We found that greater fearfulness and harsher parenting at 2 years of age predicted greater fearfulness and greater ERN amplitudes at age 4. Supporting the role of cognitive processes in this association, greater fearfulness and harsher parenting also predicted less efficient neural processing during preschool. This study provides initial evidence that performance monitoring may be a candidate process by which early parenting interacts with fearfulness to predict risk for anxiety problems. PMID:24721466
Gust, Nicole; Koglin, Ute; Petermann, Franz
2015-01-01
The present study examines the relation between knowledge of emotion regulation strategies and social behavior in preschoolers. Knowledge of emotion regulation strategies of 210 children (mean age 55 months) was assessed. Teachers rated children's social behavior with SDQ. Linear regression analysis examined how knowledge of emotion regulation strategies influenced social behavior of children. Significant effects of gender on SDQ scales "prosocial behavior", "hyperactivity", "behavior problems", and SDQ total problem scale were identified. Age was a significant predictor of SDQ scales "prosocial behavior", "hyperactivity", "problems with peers" and SDQ total problem scale. Knowledge of emotion regulation strategies predicted SDQ total problem scores. Results suggest that deficits in knowledge of emotion regulation strategies are linked with increased problem behavior.
McDonald, Renee; Grych, John H
2006-03-01
The present study investigated 2 questions pertinent to understanding developmental aspects of children's conflict appraisals: (a) Do 7- to 9-year-old children make reliable distinctions between their perceptions of conflict and their appraisals of threat and self-blame? (b) Do threat and blame appraisals mediate the association between exposure to interparental conflict and adjustment problems in this age group? Factor analysis of a new version of the Children's Perception of Interparental Conflict Scale (CPIC-Y) designed for younger children showed that 179 7- to 9-year-old children distinguished properties of conflict from their appraisals of it. Moreover, as predicted by the cognitive-contextual framework, threat and self-blame appraisals mediated the link between conflict and internalizing problems but not externalizing problems. This study provides compelling evidence that appraisals of interparental conflict can be reliably measured at relatively young ages and suggests that perceptions of threat and self-blame function similarly in 7- to 9-year-olds as they do in older children. Copyright 2006 APA, all rights reserved.
Patock-Peckham, Julie A; Morgan-Lopez, Antonio A
2007-09-01
Mediational links between parenting styles (authoritative, authoritarian, permissive), parental bond (positive, negative), depression, alcohol use and abuse were tested. A 2-group, multiple-indicator, multiple-cause structural equation model with 441 (216 female, 225 male) college students was examined. In general, a poor parental bond with one's father was highly predictive of depression, a well-known predictor of alcohol abuse and related problems for both genders. In contrast, a positive parental bond with one's father significantly mediated the positive effects of authoritative fathering on depression, which then decreased alcohol use problems for both genders. For women, a negative parental bond with one's father significantly mediated the effect of having an authoritarian father on depression, which increased alcohol use problems. These findings suggest that parental influences on pathways to alcohol abuse through depression (primarily through fathers for both genders) are distinct from pathways stemming from poor impulse control (with influences primarily from the same-sex parents for both genders).
Lipscomb, Shannon T.; Leve, Leslie D.; Shaw, Daniel S.; Neiderhiser, Jenae M.; Scaramella, Laura V.; Ge, Xiaojia; Conger, Rand D.; Reid, John B.; Reiss, David
2011-01-01
The current study examined the interplay between parental overreactivity and children’s genetic backgrounds as inferred from birth parent characteristics on the development of negative emotionality during infancy, and in turn, to individual differences in externalizing problems in toddlerhood. The sample included 361 families linked through adoption (birth parents and adoptive families). Data were collected when the children were 9-, 18-, and 27-months old. Results indicated links between individual levels and changes in negative emotionality during infancy and toddlerhood to externalizing problems early in the third year of life. Findings also revealed an interaction between birth mother negative affect and adoptive mother overreactive parenting on children’s negative emotionality. This genotype × environment interaction predicted externalizing problems indirectly through its association with negative emotionality and revealed stronger effects of genetic risk for children with less overreactive parenting from their mothers. Limitations of this study and directions for future research are discussed. PMID:22293002
Maternal Executive Function, Harsh Parenting, and Child Conduct Problems
Deater-Deckard, Kirby; Wang, Zhe; Chen, Nan; Bell, Martha Ann
2012-01-01
Background Maternal executive function and household regulation both are critical aspects of optimal childrearing, but their interplay is not understood. We tested the hypotheses that 1) the link between challenging child conduct problems and harsh parenting would be strongest for mothers with poorer executive function and weakest among those with better executive function, and 2) this mechanism would be further moderated by the degree of household chaos. Methods The socioeconomically diverse sample included 147 mothers of 3-to-7 year old children. Mothers completed questionnaires and a laboratory assessment of executive function. Results Consistent with hypotheses, harsh parenting was linked with child conduct problems only among mothers with poorer executive function. This effect was particularly strong in calm, predictable environments, but was not evident in chaotic environments. Conclusion Maternal executive function is critical to minimizing harsh parenting in the context of challenging child behavior, but this self-regulation process may not operate well in chaotic environments. PMID:22764829
Sigurdardottir, Heida Maria; Fridriksdottir, Liv Elisabet; Gudjonsdottir, Sigridur; Kristjánsson, Árni
2018-06-01
Evidence of interdependencies of face and word processing mechanisms suggest possible links between reading problems and abnormal face processing. In two experiments we assessed such high-level visual deficits in people with a history of reading problems. Experiment 1 showed that people who were worse at face matching had greater reading problems. In experiment 2, matched dyslexic and typical readers were tested, and difficulties with face matching were consistently found to predict dyslexia over and above both novel-object matching as well as matching noise patterns that shared low-level visual properties with faces. Furthermore, ADHD measures could not account for face matching problems. We speculate that reading difficulties in dyslexia are partially caused by specific deficits in high-level visual processing, in particular for visual object categories such as faces and words with which people have extensive experience. Copyright © 2018 Elsevier B.V. All rights reserved.
Déry, Michèle; Lapalme, Mélanie; Jagiellowicz, Jadzia; Poirier, Martine; Temcheff, Caroline; Toupin, Jean
2017-02-01
This study investigated the relationship between the three DSM-5 categories of oppositional defiant disorder (ODD) symptoms (irritable mood, defiant behavior, vindictive behavior) and anxiety/depression in girls and boys with conduct problems (CP) while controlling for comorbid child psychopathology at baseline. Data were drawn from an ongoing longitudinal study of 6- to 9-year-old French-Canadian children (N = 276; 40.8 % girls) receiving special educational services for CP at school and followed for 2 years. Using linear regression analysis, the results showed that irritable mood symptoms predicted a higher level of depression and anxiety in girls and boys 2 years later, whereas the behavioral symptoms of ODD (e.g., defiant, vindictive symptoms) were linked to lower depression scores. The contribution of ODD symptoms to these predictions, while statistically significant, remained modest. The usefulness of ODD irritable symptoms as a marker for identifying girls and boys with CP who are more vulnerable to developing internalizing problems is discussed.
Kochanska, Grazyna; Kim, Sanghag; Boldt, Lea J.
2013-01-01
Although children's active role in socialization has been long acknowledged, relevant research has typically focused on children's difficult temperament or negative behaviors that elicit coercive and adversarial processes, largely overlooking their capacity to act as positive, willing, even enthusiastic, active socialization agents. We studied the willing, receptive stance toward their mothers in 186 24-44-month-old children in a low-income sample. Confirmatory Factor Analysis supported a latent construct of willing stance, manifested as children's responsiveness to mothers in naturalistic interactions, responsive imitation in teaching contexts, and committed compliance with maternal prohibitions, all observed in the laboratory. Structural Equation Modeling analyses confirmed that ecological adversity undermined maternal responsiveness and responsiveness, in turn, was linked to children's willing stance. A compromised willing stance predicted externalizing behavior problems, assessed 10 months later, and fully mediated the links between maternal responsiveness and those outcomes. Ecological adversity had a direct, unmediated effect on internalizing behavior problems. Considering children's active role as willing, receptive agents capable of embracing parental influence can lead to a more complete understanding of detrimental mechanisms that link ecological adversity with antisocial developmental pathways. It can also inform research on the normative socialization process, consistent with the objectives of developmental psychopathology. PMID:24229537
Bidirectional Associations between Peer Relations and Attention Problems from 9 to 16 Years.
Ji, Linqin; Pan, Bin; Zhang, Wenxin; Zhang, Liang; Chen, Liang; Deater-Deckard, Kirby
2018-05-12
We examined the bidirectional relations between peer relations and attention problems from middle childhood through adolescence. Using data from the Longitudinal Study of Chinese Children and Adolescents (LSCCA, N = 2157, 51.9% male), three key aspects of peer relations (acceptance, rejection, and victimization) were assessed annually from 9 to 16 years of age. Attention problems were assessed at 9 and 15 years. Latent growth modeling indicated that greater attention problems at age 9 were linked with a lower intercept for peer acceptance, and higher intercepts for rejection and victimization. Also, prior lower acceptance and greater rejection and victimization, along with a higher increase over time in rejection and lower decrease over time in victimization, predicted attention problems at age 15. Cross-lagged analysis showed that attention problems were associated with less subsequent peer acceptance and greater subsequent rejection and victimization. Only peer rejection (but neither victimization nor acceptance) predicted more subsequent attention problems. Findings point to bidirectional associations between attention problems and peer relations in the developmental transition across adolescence. Evidence for differential bidirectionality of attention problems with the multiple peer experience (group versus dyadic; good versus bad) emerged, and future replications are needed.
Progress and Challenges in Subseasonal Prediction
NASA Technical Reports Server (NTRS)
Schubert, Siegfried
2003-01-01
While substantial advances have occurred over the last few decades in both weather and seasonal prediction, progress in improving predictions on subseasonal time scales (approximately 2 weeks to 2 months) has been slow. In this talk I will highlight some of the recent progress that has been made to improve forecasts on subseasonal time scales and outline the challenges that we face both from an observational and modeling perspective. The talk will be based primarily on the results and conclusions of a recent NASA-sponsored workshop that focused on the subseasonal prediction problem. One of the key conclusions of that workshop was that there is compelling evidence for predictability at forecast lead times substantially longer than two weeks, and that much of that predictability is currently untapped. Tropical diabatic heating and soil wetness were singled out as particularly important processes affecting predictability on these time scales. Predictability was also linked to various low-frequency atmospheric phenomena such as the annular modes in high latitudes (including their connections to the stratosphere), the Pacific/North American pattern, and the Madden-Julian Oscillation. I will end the talk by summarizing the recommendations and plans that have been put forward for accelerating progress on the subseasonal prediction problem.
The effects of cognitive-behavioral therapy for youth anxiety on sleep problems.
Peterman, Jeremy S; Carper, Matthew M; Elkins, R Meredith; Comer, Jonathan S; Pincus, Donna B; Kendall, Philip C
2016-01-01
The present study examined (a) whether sleep related problems (SRPs) improved following cognitive-behavioral therapy (CBT) for youth with anxiety disorders, (b) whether variables that may link anxiety and SRPs (e.g., pre-sleep arousal, family accommodation, sleep hygiene) changed during treatment, and (c) whether such changes predicted SRPs at posttreatment. Youth were diagnosed with anxiety at pretreatment and received weekly CBT that targeted their principal anxiety diagnosis at one of two specialty clinics (N=69 completers, Mage=10.86). Results indicated that parent-reported SRPs improved from pre- to post-treatment and that treatment responders with regard to anxiety yielded greater SRP improvements than nonresponders. Parent report of bedtime resistance and sleep anxiety showed significant improvements. Youth reported lower rates of SRPs compared to their parents and did not demonstrate pre- to post-treatment changes in SRPs. Pre-sleep arousal and family accommodation decreased over treatment but did not predict lower SRPs at posttreatment. Higher accommodation was correlated with greater SRPs. Sleep hygiene evidenced no change and did not mediate links between accommodation and posttreatment SRPs. Copyright © 2015 Elsevier Ltd. All rights reserved.
Wagner, Nicholas J; Gueron-Sela, Noa; Bedford, Rachael; Propper, Cathi
2018-06-12
Social-information-processing theories of parenting posit that parents' beliefs and attributions about their children's behaviors contribute to how parents interact with their children. The purpose of this study was to examine the associations between negative parenting attributions in infancy, harsh-intrusive parenting in toddlerhood, and children's internalizing problems (IPs) in early childhood. Using data from a diverse longitudinal study (n = 206), the current study used a structural equation modeling approach to test if mothers' negative attributions measured at 6 months predicted teacher ratings of children's IPs in 1st grade, as well as the extent to which observed harsh-intrusive parenting behaviors measured at ages 1, 2, and 3 years mediated this link. Maternal negative attributions in infancy predict more IPs in 1st grade, but this link becomes nonsignificant when observed harsh-intrusive parenting is included as a mediator. A significant indirect effect suggests that harsh-intrusive parenting mediates the association between early negative attributions and eventual IPs. Findings from this study identify harsh-intrusive parenting behaviors as one potential mechanism through which the effects of early attributions are carried forward to influence children's IPs. The developmental and clinical implications of these findings are discussed.
Morgan, Angharad R.; Thompson, John M.D.; Waldie, Karen E.; Cornforth, Christine M.; Turic, Darko; Sonuga-Barke, Edmund J.S.; Lam, Wen-Jiun; Ferguson, Lynnette R.; Mitchell, Edwin A.
2012-01-01
Being born small for gestational age (SGA) is a putative risk factor for the development of later cognitive and psychiatric health problems. While the inter-uterine environment has been shown to play an important role in predicting birth weight, little is known about the genetic factors that might be important. Here we test the hypothesis that neurotransmitter-regulating genes implicated in psychiatric disorders previously shown to be associated with SGA (such as attention-deficit hyperactivity disorder) are themselves predictive of SGA. DNA was collected from 227 SGA and 319 appropriate for gestational age children taking part in the Auckland Birthweight Collaborative Study. Candidate single nucleotide polymorphisms in genes regulating activity within dopamine, serotonin, glutamate and gamma-aminobutyric acid pathways were genotyped. Multiple regression analysis, controlling for potentially confounding factors, supported nominally significant associations between SGA and single nucleotide polymorphisms in COMT, HTR2A, SLC1A1 and SLC6A1. This is the first evidence that genes implicated in psychiatric disorders previously linked to SGA status themselves predict SGA. This highlights the possibility that the link between SGA and psychiatric disorders such as attention-deficit hyperactivity disorder may in part be genetically determined – that SGA marks pre-existing genetic risk for later problems. PMID:27625810
Gauthier-Duchesne, Amélie; Daspe, Marie-Ève
2017-01-01
Despite the proliferation of studies documenting outcomes in sexually abused victims, gender differences remain understudied. The bulk of studies have relied on retrospective samples of adults with insufficient representation of male victims to explore gender specificities. This study examined differential outcomes among boy and girl victims of sexual abuse. A predictive model of outcomes including abuse characteristics and sense of guilt as mediators was proposed. Path analysis was conducted with a sample of 447 sexually abused children (319 girls and 128 boys), aged 6 to 12. Being a girl was a predictor of posttraumatic stress symptoms, while being a boy was a predictor of externalizing problems. Being a boy was also associated with more severe abuse, which in turn predicted posttraumatic stress symptoms. Child’s gender was not related to perpetrator’s relationship to the child or sense of guilt. However, sense of guilt predicted posttraumatic stress symptoms and externalizing problems while perpetrator’s relationship to the child predicted externalizing problems. Gender specificities should be further studied among sexually abused children, as boys and girls appear to manifest different outcomes. Sense of guilt should be a target in intervention for sexually abused children, as results highlight its link to heightened negative outcomes. PMID:28040616
van Diepen, J B; de Groot, I W
2016-01-01
Drop-out is a complex problem in mental health care and in STEPPS. Research has revealed a variety of predicting factors and has produced contradictory results. To investigate whether the information available at the start of STEPPS can pinpoint predictors of drop-out. The ROM data for 150 patients were used to test the link between the following factors: age, gender, education, employment, substance abuse, anxiety, hostility, interpersonal relations, responsibility and social concordance with drop-out. The method used for testing was logistic regression analysis. Factors that contributed significantly to the prediction of drop-out were gender and employment status. These factors made up 16% of the explained variation (R2 Nagelkerkes) in drop-out. Gender was the strongest predictive factor. Concerning the other factors, no differences were found between groups (drop-out and non-dropouts). In its present form STEPPS does not suit a large number of the male participants. Drop-out during STEPPS is hard to predict on the basis of ROM-questionnaires. Future research should focus on preconditions and marginal conditions that influence patients to complete their training.
Chuderski, Adam; Jastrzębski, Jan
2018-02-01
A battery comprising 4 fluid reasoning tests as well as 13 working memory (WM) tasks that involved storage, recall, updating, binding, and executive control, was applied to 318 adults in order to evaluate the true relationship of reasoning ability and WM capacity (WMC) to insight problem solving, measured using 40 verbal, spatial, math, matchstick, and remote associates problems (insight problems). WMC predicted 51.8% of variance in insight problem solving and virtually explained its almost isomorphic link to reasoning ability (84.6% of shared variance). The strong link between WMC and insight pertained generally to most WM tasks and insight problems, was identical for problems solved with and without reported insight, was linear throughout the ability levels, and was not mediated by age, motivation, anxiety, psychoticism, and openness to experience. In contrast to popular views on the sudden and holistic nature of insight, the solving of insight problems results primarily from typical operations carried out by the basic WM mechanisms that are responsible for the maintenance, retrieval, transformation, and control of information in the broad range of intellectual tasks (including fluid reasoning). Little above and beyond WM is unique about insight. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Unhealthy sleep practices, conduct problems, and daytime functioning during adolescence.
Lin, Wen-Hsu; Yi, Chin-Chun
2015-02-01
Although sleep has been linked to activities in various domains of life, one under-studied link is the relationship between unhealthy sleep practices and conduct problems among adolescents. The present study investigates the influence of adolescents' unhealthy sleep practices-short sleep (e.g., less than 6 h a day), inconsistent sleep schedule (e.g., social jetlag), and sleep problems-on conduct problems (e.g., substance use, fighting, and skipping class). In addition, this study examines unhealthy sleep practices in relationship to adolescent emotional well-being, defiant attitudes, and academic performance, as well as these three domains as possible mediators of the longitudinal association between sleep practices and conduct problems. Three waves of the Taiwan Youth Project (n = 2,472) were used in this study. At the first time-point examined in this study, youth (51% male) were aged 13-17 (M = 13.3). The results indicated that all three measures of unhealthy sleep practices were related to conduct problems, such that short sleep, greater social jetlag, and more serious sleep problems were concurrently associated with greater conduct problems. In addition, short sleep and sleep problems predicted conduct problems one year later. Furthermore, these three unhealthy sleep practices were differently related to poor academic performance, low levels of emotional well-being, and defiant attitudes, and some significant indirect effects on later conduct problems through these three attributes were found. Cultural differences and suggestions for prevention are discussed.
Trim, Ryan S; Schuckit, Marc A; Smith, Tom L
2010-03-01
Previous research has shown that an early onset of drinking is associated with a range of problematic drinking outcomes in adulthood. However, earlier drinking is also linked to additional characteristics that themselves predict alcohol problems including male gender, a family history (FH) of alcoholism, age, race, parental alcoholism, depression symptoms, prior drug use, and conduct problems. This study tested the relationship between the age of first drink (AFD) and a range of risk factors that predict the onset of alcohol use. Participants were offspring from the San Diego Prospective Study (SDPS) who were at least 15 years old at the time of their most recent interview (n=147). Discrete-time survival analysis (DTSA) was used to relate multiple characteristics to the hazard function of alcohol onset across a relevant age range. The results demonstrated the predicted relationships to AFD for conduct problems, male gender, prior marijuana use, and a FH of alcoholism, even when these characteristics were estimated together. Furthermore, an interaction occurred such that offspring with both conduct problems and marijuana use were at substantially higher risk for alcohol use onset during this time period than would be predicted from the effect of these two risk factors alone. However, age at interview, ethnicity, parent education, and depressive symptoms did not predict the pattern of onset of drinking. Implications for future research and prevention efforts are discussed. Published by Elsevier Ireland Ltd.
Adolescent Alcohol Use: Protective and Predictive Parent, Peer, and Self-Related Factors
Donaldson, Candice D.; Crano, William D.
2018-01-01
Adolescent alcohol use has been linked with a multitude of problems and a trajectory predictive of problematic use in adulthood. Thus, targeting factors that enhance early prevention efforts is vital. The current study highlights variables that mitigate or predict alcohol use and heavy episodic drinking. Using Monitoring the Future (MTF) data, multiple path analytic models revealed links between parental involvement and alcohol abstinence and initiation. Parental involvement predicted enhanced self-esteem and less self-derogation and was negatively associated with peer alcohol norms for each MTF grade sampled, with stronger associations for 8th and 10th graders than 12th graders. For younger groups, self-esteem predicted increased perceptions of alcohol risk and reduced drinking. Self-derogation was associated with peers’ pro-alcohol norms, which was linked to lower risk perceptions, lower personal disapproval of use, and increased drinking. Peer influence had a stronger association with consumption for 8th and 10th graders, whereas 12th graders’ drinking was related to personal factors of alcohol risk perception and disapproval. In all grades, general alcohol use had a strong connection to heavy episodic drinking within the past 2 weeks. Across-grade variations in association of parent, peer, and personal factors suggest the desirability of tailored interventions focused on specific factors for each grade level, with the overall goal of attenuating adolescent alcohol use. PMID:27562038
Anxiety, Depression and Emotion Regulation Among Regular Online Poker Players.
Barrault, Servane; Bonnaire, Céline; Herrmann, Florian
2017-12-01
Poker is a type of gambling that has specific features, including the need to regulate one's emotion to be successful. The aim of the present study is to assess emotion regulation, anxiety and depression in a sample of regular poker players, and to compare the results of problem and non-problem gamblers. 416 regular online poker players completed online questionnaires including sociodemographic data, measures of problem gambling (CPGI), anxiety and depression (HAD scale), and emotion regulation (ERQ). The CPGI was used to divide participants into four groups according to the intensity of their gambling practice (non-problem, low risk, moderate risk and problem gamblers). Anxiety and depression were significantly higher among severe-problem gamblers than among the other groups. Both significantly predicted problem gambling. On the other hand, there was no difference between groups in emotion regulation (cognitive reappraisal and expressive suppression), which was linked neither to problem gambling nor to anxiety and depression (except for cognitive reappraisal, which was significantly correlated to anxiety). Our results underline the links between anxiety, depression and problem gambling among poker players. If emotion regulation is involved in problem gambling among poker players, as strongly suggested by data from the literature, the emotion regulation strategies we assessed (cognitive reappraisal and expressive suppression) may not be those involved. Further studies are thus needed to investigate the involvement of other emotion regulation strategies.
Clerkin, Elise M; Barnett, Nancy
2012-05-01
Our goal was to test the separate and interactive effects of drinking motives and social anxiety symptoms in predicting drinking-related consumption and problems. Participants (N=730; 59.7% female) were undergraduate college students who completed measures of social anxiety symptoms, drinking motives, alcohol consumption, and drinking problems. Greater social anxiety symptoms were significantly associated with less alcohol consumption, and there was some evidence that greater social anxiety symptoms were also associated with greater alcohol-relevant problems. Significant interactions between social anxiety and motives indicated that a) alcohol use was most pronounced for individuals high in enhancement motives and low in social anxiety symptoms; and b) among participants low in coping motives, drinking problems were greater for individuals high (vs. low) in social anxiety symptoms. More fully identifying the individual difference factors that link social anxiety symptoms with drinking outcomes is important for informing prevention and intervention approaches. Copyright © 2012 Elsevier Ltd. All rights reserved.
Clerkin, Elise M.; Barnett, Nancy
2012-01-01
PURPOSE Our goal was to test the separate and interactive effects of drinking motives and social anxiety symptoms in predicting drinking-related consumption and problems. METHODS Participants (N=730; 59.7% Female) were undergraduate college students who completed measures of social anxiety symptoms, drinking motives, alcohol consumption, and drinking problems. RESULTS Greater social anxiety symptoms were significantly associated with less alcohol consumption, and there was some evidence that greater social anxiety symptoms were also associated with greater alcohol-relevant problems. Significant interactions between social anxiety and motives indicated that a) alcohol use was most pronounced for individuals high in enhancement motives and low in social anxiety symptoms; and b) among participants low in coping motives, drinking problems were greater for individuals high (vs. low) in social anxiety symptoms. CONCLUSIONS More fully identifying the individual difference factors that link social anxiety symptoms with drinking outcomes is important for informing prevention and intervention approaches. PMID:22365887
Touch Processing and Social Behavior in ASD.
O Miguel, Helga; Sampaio, Adriana; Martínez-Regueiro, Rocío; Gómez-Guerrero, Lorena; López-Dóriga, Cristina Gutiérrez; Gómez, Sonia; Carracedo, Ángel; Fernández-Prieto, Montse
2017-08-01
Abnormal patterns of touch processing have been linked to core symptoms in ASD. This study examined the relation between tactile processing patterns and social problems in 44 children and adolescents with ASD, aged 6-14 (M = 8.39 ± 2.35). Multiple linear regression indicated significant associations between touch processing and social problems. No such relationships were found for social problems and autism severity. Within touch processing, patterns of hyper-responsiveness and hypo-responsiveness best predicted social problems, whereas sensory-seeking did not. These results support that atypical touch processing in individuals with ASD might be contributing to the social problems they present. Moreover, it the need to explore more in depth the contribution of sensory features to the ASD phenotype.
Timmermans, Maartje; van Lier, Pol A C; Koot, Hans M
2008-04-01
Health risk behaviors like substance use (alcohol, tobacco, soft/hard drugs) and risky sexual behavior become more prevalent in adolescence. Children with behavior problems are thought to be prone to engage in health risk behaviors later in life. It is, however, unclear which problems within the externalizing spectrum account for these outcomes. Three hundred and nine children were followed from age 4/5 years to 18 years (14-year follow-up). Level and course of parent-rated opposition, physical aggression, status violations and property violations were used to predict adolescent-reported substance use and risky sexual behavior at age 18 years. Both level and change in physical aggression were unique predictors of all forms of adolescent health risk behavior. Levels of status violations predicted smoking and soft drug use only, while change in property violations predicted each of the health risk behaviors. The links between opposition and health risk behaviors were accounted for by co-occurring problem behaviors. Of externalizing problems, physical aggression is the best predictor of adolescent substance use and risky sexual behavior from childhood onwards. Possible explanations and implications of these findings, and future research directions are discussed.
Kim, Min Jung; Mason, W. Alex; Herrenkohl, Todd I.; Catalano, Richard F.; Toumbourou, John W.; Hemphill, Sheryl A.
2016-01-01
This study examined cross-national similarities in a developmental model linking early age of alcohol use onset to frequent drinking and heavy drinking and alcohol problems 1 and 2 years later in a binational sample of 13-year-old students from 2 states: Washington State, United States, and Victoria, Australia (N = 1,833). A range of individual, family, school, and peer influences were included in analyses to investigate their unique and shared contribution to development of early and more serious forms of alcohol use and harms from misuse. Data were collected annually over a 3-year period from ages 13 to 15. Analyses were conducted using multiple-group structural equation modeling. For both states, early use of alcohol predicted frequent drinking, which predicted alcohol problems. Family protective influences had no direct effects on heavy drinking, nor effects on alcohol harm in either state, whereas school protection directly reduced the risk of heavy drinking in both states. Exposure to antisocial peers and siblings predicted a higher likelihood of heavy drinking and alcohol harm for students in both Washington and Victoria. Implications for the prevention of adolescent alcohol problems are discussed. PMID:27699620
Archer, T; Adolfsson, B; Karlsson, E
2008-08-01
Three studies that examined the links between affective personality, as constructed from responses to the Positive Affect (PA) and Negative Affect (NA) Scale (PANAS), and individuals' self-report of self-esteem, intrinsic motivation and Beck's Depression Inventory (BDI) depression in high school students and persons in working occupations are described. Self-report estimations of several other neuropsychiatric and psychosocial variables including, the Uppsala Sleep Inventory (USI), the Hospital Anxiety and Depression (HAD) test, Dispositional optimism, Locus of control, the Subjective Stress Experience test (SSE) and the Stress-Energy (SE) test, were also derived. Marked effects due to affective personality type upon somatic and psychological stress, anxiety and depression, self-esteem, internal and external locus of control, optimism, stress and energy, intrinsic motivation, external regulation, identified regulation, major sleep problems, problems falling asleep, and psychophysiological problems were observed; levels of self-esteem, self-motivation and BDI-depression all produced substantial effects on health and well-being. Regression analyses indicated PA was predicted by dispositional optimism (thrice), energy (thrice), and intrinsic motivation, and counter predicted by depression (twice) and stress (twice); and NA by anxiety (twice), stress (twice), psychological stress, identified regulation, BDI depression and psychophysiological problems, and counter predicted by internal locus of control and self-esteem. BDI-depression was predicted by negative affect, major sleep problems and psychophysiological problems (Study III), self-esteem by dispositional optimism and energy, and counter predicted by anxiety, depression and stress (Study I), and intrinsic motivation by dispositional optimism, energy, PA and self-esteem (Study II). These convergent findings are interpreted from a perspective of the cognitive-emotional expressions underlying behavioural or presymptomatic profiles presenting predispositions for health or ill health.
ERIC Educational Resources Information Center
Konold, Timothy R.; Pianta, Robert C.
2005-01-01
School readiness assessment is a prominent feature of early childhood education. Because the construct of readiness is multifaceted, we examined children's patterns on multiple indicators previously found to be both theoretically and empirically linked to school readiness: social skill, interactions with parents, problem behavior, and performance…
ERIC Educational Resources Information Center
Kochanska, Grazyna; Kim, Sanghag
2013-01-01
Background: Research has shown that interactions between young children's temperament and the quality of care they receive predict the emergence of positive and negative socioemotional developmental outcomes. This multimethod study addresses such interactions, using observed and mother-rated measures of difficult temperament, children's…
ERIC Educational Resources Information Center
Sanderson, Bettie; Kurdek, Lawrence A.
1993-01-01
Examined relationship satisfaction and commitment among African-American (n=34 couples) and white (n=61 couples) dating heterosexual couples. Found that extent to which variables from interdependence, individual differences, and problem-solving models were linked to both relationship satisfaction and relationship commitment did not differ for…
ERIC Educational Resources Information Center
Woods, Sara E.; Menna, Rosanne; McAndrew, Annamaria J.
2017-01-01
Aggression in early childhood has been found to predict future psychopathology, academic problems, and delinquency. In a sample of 136 mother-child pairs (M[subscript age] = 4 years, 11 months, SD = 11 months, 58% boys) associations among mothers' responding with distress to children's negative emotions, children's emotional control, and…
ERIC Educational Resources Information Center
Dever, Bridget V.
2016-01-01
Within the expectancy-value framework, much work has been done linking expectancies and task values to academic outcomes such as performance, persistence, and choice. Research on the associations between student motivation (including efficacy and task values) and behavioral and emotional problems, however, is nascent. The present study examined a…
ERIC Educational Resources Information Center
Barnes, J. C.; Beaver, Kevin M.; Boutwell, Brian B.
2013-01-01
Research utilizing individual-level data has reported a link between intelligence (IQ) scores and health problems, including early mortality risk. A growing body of evidence has found similar associations at higher levels of aggregation such as the state- and national-level. At the same time, individual-level research has suggested the…
ERIC Educational Resources Information Center
Scaramella, Laura V.; Conger, Rand D.
2003-01-01
Examined intergenerational transmission of hostile parenting, moderating effects of child negative emotional reactivity, and links between second generation (G2) hostile parenting and G3 problem behaviors. Found that G1 mothers' hostile parenting when target participant was an adolescent (G2) predicted G2 hostile parenting toward their young child…
Oshri, Assaf; Kogan, Steven; Liu, Sihong; Sweet, Lawrence; Mackillop, James
2017-12-01
African American men experience increases in smoking during the young adult transition. Exposure to childhood adversity, a risk factor which disproportionately affects African American men, has been identified as a robust precursor to health risk behavior in general and cigarette smoking in particular. The intermediate mechanisms that transmit the influence of early adversity to smoking behavior are not well understood. We tested a model of the escalation of smoking behaviors among young adult African American men, investigating sleep disturbance and delayed reward discounting as intermediate factors linking adverse childhood experiences with smoking. Hypotheses were tested with three waves of data (M age-T1 = 20.34, M age-T2 = 21.92, M age-T3 = 23.02) from 505 African American men living in rural counties in South Georgia. Men provided self-report data on their adverse childhood experiences, sleep problems, and smoking behavior using audio-assisted computer self-interviews. Men also completed a computer-based delayed reward discounting task. Structural equation modeling analyses supported our hypotheses: Adverse childhood experiences predicted poor sleep adequacy, which forecast increases in delayed reward discounting; discounting, in turn, predicted increased smoking. Significant indirect pathways were detected linking adversity to discounting via sleep adequacy and linking sleep adequacy to smoking via discounting. Prevention and intervention researchers can draw on these findings to develop programs that focus on sleep adequacy to reduce smoking in African American men exposed to childhood adversity.
The Power of Implicit Social Relation in Rating Prediction of Social Recommender Systems
Reafee, Waleed; Salim, Naomie; Khan, Atif
2016-01-01
The explosive growth of social networks in recent times has presented a powerful source of information to be utilized as an extra source for assisting in the social recommendation problems. The social recommendation methods that are based on probabilistic matrix factorization improved the recommendation accuracy and partly solved the cold-start and data sparsity problems. However, these methods only exploited the explicit social relations and almost completely ignored the implicit social relations. In this article, we firstly propose an algorithm to extract the implicit relation in the undirected graphs of social networks by exploiting the link prediction techniques. Furthermore, we propose a new probabilistic matrix factorization method to alleviate the data sparsity problem through incorporating explicit friendship and implicit friendship. We evaluate our proposed approach on two real datasets, Last.Fm and Douban. The experimental results show that our method performs much better than the state-of-the-art approaches, which indicates the importance of incorporating implicit social relations in the recommendation process to address the poor prediction accuracy. PMID:27152663
The predictive mind and the experience of visual art work
Kesner, Ladislav
2014-01-01
Among the main challenges of the predictive brain/mind concept is how to link prediction at the neural level to prediction at the cognitive-psychological level and finding conceptually robust and empirically verifiable ways to harness this theoretical framework toward explaining higher-order mental and cognitive phenomena, including the subjective experience of aesthetic and symbolic forms. Building on the tentative prediction error account of visual art, this article extends the application of the predictive coding framework to the visual arts. It does so by linking this theoretical discussion to a subjective, phenomenological account of how a work of art is experienced. In order to engage more deeply with a work of art, viewers must be able to tune or adapt their prediction mechanism to recognize art as a specific class of objects whose ontological nature defies predictability, and they must be able to sustain a productive flow of predictions from low-level sensory, recognitional to abstract semantic, conceptual, and affective inferences. The affective component of the process of predictive error optimization that occurs when a viewer enters into dialog with a painting is constituted both by activating the affective affordances within the image and by the affective consequences of prediction error minimization itself. The predictive coding framework also has implications for the problem of the culturality of vision. A person’s mindset, which determines what top–down expectations and predictions are generated, is co-constituted by culture-relative skills and knowledge, which form hyperpriors that operate in the perception of art. PMID:25566111
The predictive mind and the experience of visual art work.
Kesner, Ladislav
2014-01-01
Among the main challenges of the predictive brain/mind concept is how to link prediction at the neural level to prediction at the cognitive-psychological level and finding conceptually robust and empirically verifiable ways to harness this theoretical framework toward explaining higher-order mental and cognitive phenomena, including the subjective experience of aesthetic and symbolic forms. Building on the tentative prediction error account of visual art, this article extends the application of the predictive coding framework to the visual arts. It does so by linking this theoretical discussion to a subjective, phenomenological account of how a work of art is experienced. In order to engage more deeply with a work of art, viewers must be able to tune or adapt their prediction mechanism to recognize art as a specific class of objects whose ontological nature defies predictability, and they must be able to sustain a productive flow of predictions from low-level sensory, recognitional to abstract semantic, conceptual, and affective inferences. The affective component of the process of predictive error optimization that occurs when a viewer enters into dialog with a painting is constituted both by activating the affective affordances within the image and by the affective consequences of prediction error minimization itself. The predictive coding framework also has implications for the problem of the culturality of vision. A person's mindset, which determines what top-down expectations and predictions are generated, is co-constituted by culture-relative skills and knowledge, which form hyperpriors that operate in the perception of art.
Luk, Jeremy W; King, Kevin M; McCarty, Carolyn A; McCauley, Elizabeth; Vander Stoep, Ann
2017-07-01
Parental warmth and knowledge are protective factors against substance use, whereas parental psychological control is a risk factor. However, the interpretation of parenting and its effects on developmental outcomes may vary cross-culturally. This study examined direct and indirect effects of three parenting dimensions on substance use across Asian/Pacific Islander (API) and European Americans. A community sample of 97 API and 255 European Americans were followed from Grades 6 to 12. Participants reported on parenting in Grade 7, academic achievement and externalizing behaviors in Grades 7 and 8, and substance use behaviors in Grades 7, 9, and 12. Direct effects of parenting were not moderated by race. Overall, mother psychological control was a risk factor for substance use problems in Grade 9, whereas father knowledge was protective against alcohol use in Grade 9, substance use problems in Grades 9 and 12, and alcohol dependence in Grade 12. Moderated mediation analyses indicated significant mediational links among European Americans only: Mother knowledge predicted fewer externalizing problems in Grade 8, which in turn predicted fewer substance use problems in Grades 9 and 12. Father warmth predicted better academic achievement in Grade 8, which in turn predicted fewer substance use problems in Grades 9 and 12, as well as alcohol and marijuana dependence in Grade 12. Better academic achievement and fewer externalizing behaviors explain how positive parenting reduces substance use risk among European Americans. Promoting father knowledge of adolescents' whereabouts can reduce substance use risk among both European and API Americans.
Reliable prediction intervals with regression neural networks.
Papadopoulos, Harris; Haralambous, Haris
2011-10-01
This paper proposes an extension to conventional regression neural networks (NNs) for replacing the point predictions they produce with prediction intervals that satisfy a required level of confidence. Our approach follows a novel machine learning framework, called Conformal Prediction (CP), for assigning reliable confidence measures to predictions without assuming anything more than that the data are independent and identically distributed (i.i.d.). We evaluate the proposed method on four benchmark datasets and on the problem of predicting Total Electron Content (TEC), which is an important parameter in trans-ionospheric links; for the latter we use a dataset of more than 60000 TEC measurements collected over a period of 11 years. Our experimental results show that the prediction intervals produced by our method are both well calibrated and tight enough to be useful in practice. Copyright © 2011 Elsevier Ltd. All rights reserved.
Dynamic analysis of space structures including elastic, multibody, and control behavior
NASA Technical Reports Server (NTRS)
Pinson, Larry; Soosaar, Keto
1989-01-01
The problem is to develop analysis methods, modeling stategies, and simulation tools to predict with assurance the on-orbit performance and integrity of large complex space structures that cannot be verified on the ground. The problem must incorporate large reliable structural models, multi-body flexible dynamics, multi-tier controller interaction, environmental models including 1g and atmosphere, various on-board disturbances, and linkage to mission-level performance codes. All areas are in serious need of work, but the weakest link is multi-body flexible dynamics.
Hoppmann, Christiane A; Coats, Abby Heckman; Blanchard-Fields, Fredda
2008-07-01
Qualitative interviews on family and financial problems from 332 adolescents, young, middle-aged, and older adults, demonstrated that developmentally relevant goals predicted problem-solving strategy use over and above problem domain. Four focal goals concerned autonomy, generativity, maintaining good relationships with others, and changing another person. We examined both self- and other-focused problem-solving strategies. Autonomy goals were associated with self-focused instrumental problem solving and generative goals were related to other-focused instrumental problem solving in family and financial problems. Goals of changing another person were related to other-focused instrumental problem solving in the family domain only. The match between goals and strategies, an indicator of problem-solving adaptiveness, showed that young individuals displayed the greatest match between autonomy goals and self-focused problem solving, whereas older adults showed a greater match between generative goals and other-focused problem solving. Findings speak to the importance of considering goals in investigations of age-related differences in everyday problem solving.
Marsh, Penny; Beauchaine, Theodore P.; Williams, Bailey
2009-01-01
Although deficiencies in emotional responding have been linked to externalizing behaviors in children, little is known about how discrete response systems (e.g., expressive, physiological) are coordinated during emotional challenge among these youth. We examined time-linked correspondence of sad facial expressions and autonomic reactivity during an empathy-eliciting task among boys with disruptive behavior disorders (n = 31) and controls (n = 23). For controls, sad facial expressions were associated with reduced sympathetic (lower skin conductance level, lengthened cardiac preejection period [PEP]) and increased parasympathetic (higher respiratory sinus arrhythmia [RSA]) activity. In contrast, no correspondence between facial expressions and autonomic reactivity was observed among boys with conduct problems. Furthermore, low correspondence between facial expressions and PEP predicted externalizing symptom severity, whereas low correspondence between facial expressions and RSA predicted internalizing symptom severity. PMID:17868261
Breastfeeding duration and offspring conduct problems: The moderating role of genetic risk.
Jackson, Dylan B
2016-10-01
A sizable body of research has examined associations between breastfeeding and various facets of offspring development, including childhood behavioral problems. Notwithstanding the number of studies on the topic, breastfeeding has not consistently been linked to child misbehaviors. Moreover, empirical examinations of whether breastfeeding is differentially predictive of conduct problems among individuals with varying degrees of genetic risk are lacking. The present study examines whether a short duration of breastfeeding and genetic risk interact to predict conduct problems during childhood. A genetically informative design is employed to examine a subsample of twins from the Early Childhood Longitudinal Study: Birth Cohort (ECLS-B), a nationally representative sample of American children. The findings suggest that a shorter duration of breastfeeding only enhances the risk of offspring conduct problems among children who possess high levels of genetic risk. Conversely, longer breastfeeding durations were found to protect against childhood behavioral problems when genetic risk was high. Indicators of genetic risk may help to distinguish individuals whose behavioral development is most sensitive to the duration of breastfeeding. Future research should seek to replicate and extend these findings by considering genetic factors as potential markers of differential susceptibility to breastfeeding duration. Copyright © 2016 Elsevier Ltd. All rights reserved.
Ormel, J; Oldehinkel, A J; Ferdinand, R F; Hartman, C A; De Winter, A F; Veenstra, R; Vollebergh, W; Minderaa, R B; Buitelaar, J K; Verhulst, F C
2005-12-01
We investigated the links between familial loading, preadolescent temperament, and internalizing and externalizing problems in adolescence, hereby distinguishing effects on maladjustment in general versus dimension-specific effects on either internalizing or externalizing problems. In a population-based sample of 2230 preadolescents (10-11 years) familial loading (parental lifetime psychopathology) and offspring temperament were assessed at baseline by parent report, and offspring psychopathology at 2.5-years follow-up by self-report, teacher report and parent report. We used purified measures of temperament and psychopathology and partialled out shared variance between internalizing and externalizing problems. Familial loading of internalizing psychopathology predicted offspring internalizing but not externalizing problems, whereas familial loading of externalizing psychopathology predicted offspring externalizing but not internalizing problems. Both familial loadings were associated with Frustration, low Effortful Control, and Fear. Frustration acted as a general risk factor predicting severity of maladjustment; low Effortful Control and Fear acted as dimension-specific risk factors that predicted a particular type of psychopathology; whereas Shyness, High-Intensity Pleasure, and Affiliation acted as direction markers that steered the conditional probability of internalizing versus externalizing problems, in the event of maladjustment. Temperament traits mediated one-third of the association between familial loading and psychopathology. Findings were robust across different composite measures of psychopathology, and applied to girls as well as boys. With regard to familial loading and temperament, it is important to distinguish general risk factors (Frustration) from dimension-specific risk factors (familial loadings, Effortful Control, Fear), and direction markers that act as pathoplastic factors (Shyness, High-Intensity Pleasure, Affiliation) from both types of risk factors. About one-third of familial loading effects on psychopathology in early adolescence are mediated by temperament.
CrossLink: a novel method for cross-condition classification of cancer subtypes.
Ma, Chifeng; Sastry, Konduru S; Flore, Mario; Gehani, Salah; Al-Bozom, Issam; Feng, Yusheng; Serpedin, Erchin; Chouchane, Lotfi; Chen, Yidong; Huang, Yufei
2016-08-22
We considered the prediction of cancer classes (e.g. subtypes) using patient gene expression profiles that contain both systematic and condition-specific biases when compared with the training reference dataset. The conventional normalization-based approaches cannot guarantee that the gene signatures in the reference and prediction datasets always have the same distribution for all different conditions as the class-specific gene signatures change with the condition. Therefore, the trained classifier would work well under one condition but not under another. To address the problem of current normalization approaches, we propose a novel algorithm called CrossLink (CL). CL recognizes that there is no universal, condition-independent normalization mapping of signatures. In contrast, it exploits the fact that the signature is unique to its associated class under any condition and thus employs an unsupervised clustering algorithm to discover this unique signature. We assessed the performance of CL for cross-condition predictions of PAM50 subtypes of breast cancer by using a simulated dataset modeled after TCGA BRCA tumor samples with a cross-validation scheme, and datasets with known and unknown PAM50 classification. CL achieved prediction accuracy >73 %, highest among other methods we evaluated. We also applied the algorithm to a set of breast cancer tumors derived from Arabic population to assign a PAM50 classification to each tumor based on their gene expression profiles. A novel algorithm CrossLink for cross-condition prediction of cancer classes was proposed. In all test datasets, CL showed robust and consistent improvement in prediction performance over other state-of-the-art normalization and classification algorithms.
Processes linking adolescent well-being, marital love, and coparenting.
Baril, Megan E; Crouter, Ann C; McHale, Susan M
2007-12-01
This study examined coparenting in a sample of 177 two-parent families with firstborn adolescents by using annual home interview data from mothers, fathers, and adolescents. With a path-analytic approach and with earlier problem behaviors controlled for, coparenting conflict predicted relative increases in adolescent risky behavior over 2 years. In addition, evidence for 2 types of mediation was found. Marital love mediated the link between adolescents' early risky behavior and coparenting 1 year later, and coparenting conflict mediated the link between marital love and adolescents' risky behavior 1 year later. Linkages did not emerge for coparenting cooperation or triangulation. Interventions that are focused on the marital and coparental relationships in families with adolescents may modify trajectories of adolescent risky behavior.
Tsui, Tiffany Y L; Lahat, Ayelet; Schmidt, Louis A
2017-10-01
Although childhood shyness has been linked to social anxiety problems, the factors playing a role in this association have gone largely unexplored. Here we examined the potential moderating roles of sex and age on this relation in a sample of 119 (75 girls) children (10-12 years) and adolescents (14-16 years). As predicted, shyness was positively associated with social anxiety symptoms. Sex, but not age, served as a moderating factor in linking shyness and social anxiety. Specifically, shyness was more strongly associated with social anxiety symptoms among girls than boys. These results suggest the importance of considering sex differences when examining the relation between shyness and social anxiety in childhood and adolescence.
Sidor, Anna; Fischer, Cristina; Cierpka, Manfred
2017-01-01
Difficult conditions during childhood can limit an individual's development in many ways. Factors such as being raised in an at-risk family, child temperamental traits or maternal traits can potentially influence a child's later behaviour. The present study investigated the extent of regulatory problems in 6-month-old infants and their link to temperamental traits and impact on externalizing and internalizing problems at 36 months. Moderating effects of maternal distress and maternal depressive symptoms were tested as well. In a quasi-experimental, longitudinal study, a sample of 185 mother-infant dyads at psychosocial risk was investigated at 6 months with SFS (infants' regulatory problems) and at 3 years with CBCL (children's behavioural problems), EAS (children's temperament), ADS (maternal depressive symptoms) and PSI-SF (maternal stress). A hierarchical regression analysis yielded a significant association between infants' regulatory problems and both externalizing and internalizing behaviour problems at age 3 (accounting for 16% and 14% variance), with both externalizing and internalizing problems being linked to current maternal depressive symptoms (12 and 9% of the variance). Externalizing and internalizing problems were found to be related also to children's temperamental difficulty (18 and 13% of variance) and their negative emotionality. With temperamental traits having been taken into account, only feeding problems at 6 months contributed near-significant to internalizing problems at 3 years. Our results underscore the crucial role of temperament in the path between early regulatory problems and subsequent behavioural difficulties. Children's unfavourable temperamental predispositions such as negative emotionality and generally "difficult temperament" contributed substantially to both externalizing and internalizing behavioural problems in the high-risk sample. The decreased predictive power of regulatory problems following the inclusion of temperamental variables indicates a mediation effect of temperamental traits in the path between early regulatory problems and subsequent behavioural problems. Our results support the main effects of a child's temperament, and to some degree maternal depressive symptoms, rather than the diathesis stress model of interaction between risky environment and temperamental traits. Trial registration D10025651 (NZFH).
Krishnakumar, Ambika; Narine, Lutchmie; Soonthorndhada, Amara; Thianlai, Kanchana
2015-03-01
To examine gender variations in the linkages among family stressors, home demands and responsibilities, coping resources, social connectedness, and older adult health problems. Data were collected from 3,800 elderly participants (1,654 men and 2,146 women) residing in Kanchanaburi province, Thailand. Findings indicated gender variations in the levels of these constructs and in the mediational pathways. Thai women indicated greater health problems than men. Emotional empathy was the central variable that linked financial strain, home demands and responsibilities, and older adult health problems through social connectedness. Financial strain (and negative life events for women) was associated with lowered coping self-efficacy and increased health problems. The model indicated greater strength in predicting female health problems. Findings support gender variations in the relationships between ecological factors and older adult health problems. © The Author(s) 2014.
Barrios, Chelsey S; Jay, Samantha Y; Smith, Victoria C; Alfano, Candice A; Dougherty, Lea R
2018-01-01
Little research has examined the processes underlying children's persistent sleep problems and links with later psychopathology. The current study examined the stability of parent-child sleep interactions as assessed with the parent-reported Parent-Child Sleep Interactions Scale (PSIS) and examined whether sleep interactions in preschool-age children predict sleep problems and psychiatric symptoms later in childhood. Participants included 108 preschool-age children (50% female) and their parents. Parents completed the PSIS when children were 3-5 years (T1) and again when they were 6-9 years (T2). The PSIS includes three subscales-Sleep Reinforcement (reassurance of child sleep behaviors), Sleep Conflict (parent-child conflict at bedtime), Sleep Dependence (difficulty going to sleep without parent)-and a total score. Higher scores indicate more problematic bedtime interactions. Children's sleep problems and psychiatric symptoms at T1 and T2 were assessed with a clinical interview. PSIS scores were moderately stable from T1 to T2, and the factor structure of the PSIS remained relatively consistent over time. Higher total PSIS scores at T1 predicted increases in children's sleep problems at T2. Higher PSIS Sleep Conflict scores at T1 predicted increases in oppositional defiant disorder symptoms at T2. Children with more sleep problems and higher PSIS Sleep Reinforcement scores at T1 showed increases in attention deficit/hyperactivity disorder, depressive, and anxiety symptoms at T2. These findings provide evidence for the predictive validity of the PSIS and highlight the importance of early parent-child sleep interactions in the development of sleep and psychiatric symptoms in childhood. Parent-child sleep interactions may serve as a useful target for interventions.
Child behavior and sibling relationship quality: A cross-lagged analysis.
Pike, Alison; Oliver, Bonamy R
2017-03-01
Bidirectional associations between sibling relationships and children's problem behaviors are robust, and links with prosocial behavior have also been reported. Using cross-lagged models, we were able to conservatively test temporal directions of links between positive and negative aspects of sibling relationships and children's prosocial behavior and conduct problems across a 3-year time span in middle childhood. The Avon Longitudinal Study of Parents and Children (ALSPAC; http://www.bristol.ac.uk/alspac/researchers/data-access/data-dictionary/) is an ongoing population-based study designed to investigate the effects of a wide range of factors on children's health and development. For the purposes of the current analyses, we included 2,043 ALSPAC families who had just 1 older sibling as well as the target child, with an age gap of no more than 5 years. Mothers reported about the quality of the sibling relationship and both children's prosocial behavior and conduct problems when the target child was 4 years of age and again when the target child was 7 years old. Confirming our hypothesis, individual child behavior was predictive of sibling relationship quality, and sibling relationship quality was predictive of later child behavior, providing robust evidence of bidirectionality for both prosocial behavior and conduct problems. It would be consistent to expect that an improvement in either sibling relationship quality or individual children's behavior could have a positive spill over effect. We also found evidence of older sibling dominance in the domain of prosocial behavior and the positive aspects of sibling interaction. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Child Behavior and Sibling Relationship Quality: A Cross-Lagged Analysis
2016-01-01
Bidirectional associations between sibling relationships and children’s problem behaviors are robust, and links with prosocial behavior have also been reported. Using cross-lagged models, we were able to conservatively test temporal directions of links between positive and negative aspects of sibling relationships and children’s prosocial behavior and conduct problems across a 3-year time span in middle childhood. The Avon Longitudinal Study of Parents and Children (ALSPAC; http://www.bristol.ac.uk/alspac/researchers/data-access/data-dictionary/) is an ongoing population-based study designed to investigate the effects of a wide range of factors on children’s health and development. For the purposes of the current analyses, we included 2,043 ALSPAC families who had just 1 older sibling as well as the target child, with an age gap of no more than 5 years. Mothers reported about the quality of the sibling relationship and both children’s prosocial behavior and conduct problems when the target child was 4 years of age and again when the target child was 7 years old. Confirming our hypothesis, individual child behavior was predictive of sibling relationship quality, and sibling relationship quality was predictive of later child behavior, providing robust evidence of bidirectionality for both prosocial behavior and conduct problems. It would be consistent to expect that an improvement in either sibling relationship quality or individual children’s behavior could have a positive spill over effect. We also found evidence of older sibling dominance in the domain of prosocial behavior and the positive aspects of sibling interaction. PMID:27797540
Pitpitan, Eileen V.; Kalichman, Seth C.; Eaton, Lisa A.; Sikkema, Kathleen J.; Watt, Melissa H.; Skinner, Donald
2012-01-01
Gender-based violence is a key determinant of HIV infection among women in South Africa as elsewhere. However, research has not examined potential mediating processes to explain the link between experiencing abuse and engaging in HIV sexual risk behavior. Previous studies suggest that alcohol use and mental health problems may explain how gender-based violence predicts sexual risk. In a prospective study, we examined whether lifetime history of gender-based violence indirectly affects future sexual risk behavior through alcohol use, depression and post-traumatic stress disorder (PTSD) in a high-risk socio-environmental context. We recruited a cohort of 560 women from alcohol drinking venues in a Cape Town, South African township. Participants completed computerized interviews at baseline and 4 months later. We tested prospective mediating associations between gender-based violence, alcohol use, depression, PTSD, and sexual risk behavior. There was a significant indirect effect of gender-based violence on sexual risk behavior through alcohol use, but not mental health problems. Women who were physically and sexually abused drank more, which in turn predicted more unprotected sex. We did not find a mediated relationship between alcohol use and sexual risk behavior through the experience of recent abuse or mental health problems. Alcohol use explains the link between gender-based violence and sexual risk behavior among women attending drinking venues in Cape Town, South Africa. Efforts to reduce HIV risk in South Africa by addressing gender-based violence must also address alcohol use. PMID:22832324
Pitpitan, Eileen V; Kalichman, Seth C; Eaton, Lisa A; Sikkema, Kathleen J; Watt, Melissa H; Skinner, Donald
2012-10-01
Gender-based violence is a key determinant of HIV infection among women in South Africa as elsewhere. However, research has not examined potential mediating processes to explain the link between experiencing abuse and engaging in HIV sexual risk behavior. Previous studies suggest that alcohol use and mental health problems may explain how gender-based violence predicts sexual risk. In a prospective study, we examined whether lifetime history of gender-based violence indirectly affects future sexual risk behavior through alcohol use, depression and post-traumatic stress disorder (PTSD) in a high-risk socio-environmental context. We recruited a cohort of 560 women from alcohol drinking venues in a Cape Town, South African township. Participants completed computerized interviews at baseline and 4 months later. We tested prospective mediating associations between gender-based violence, alcohol use, depression, PTSD, and sexual risk behavior. There was a significant indirect effect of gender-based violence on sexual risk behavior through alcohol use, but not mental health problems. Women who were physically and sexually abused drank more, which in turn predicted more unprotected sex. We did not find a mediated relationship between alcohol use and sexual risk behavior through the experience of recent abuse or mental health problems. Alcohol use explains the link between gender-based violence and sexual risk behavior among women attending drinking venues in Cape Town, South Africa. Efforts to reduce HIV risk in South Africa by addressing gender-based violence must also address alcohol use. Copyright © 2012 Elsevier Ltd. All rights reserved.
Johansen, Ragnhild; Melle, Ingrid; Iversen, Valentina Cabral; Hestad, Knut
2013-11-01
The quality of the therapeutic alliance is associated with engagement in- and thus important to the outcome of- treatment in schizophrenia. In non-psychotic disorders, general personality traits and individual patterns of interpersonal problems have been linked to the formation and quality of the therapeutic alliance. The role of these factors in relation to therapeutic alliance has not previously been explored in schizophrenia spectrum disorders. To investigate associations between personality traits, interpersonal problems and the quality of the therapeutic alliance in early schizophrenia spectrum disorders. Demographic and clinical characteristics including Positive and Negative Syndrome Scale (PANSS) scores were assessed in 42 patients. Personality traits and interpersonal problems were assessed with the NEO Five factor Inventory (NEO-FFI) and the circumplex model of the Inventory of Interpersonal Problems (IIP-64C). Therapeutic alliance was measured with the Working Alliance Inventory - short form (WAI-S). Patient WAI-S scores were predicted by IIP-64C Submissive/Hostile interpersonal problems, age and PANSS excitative symptoms. Therapist WAI-S scores were predicted by NEO-FFI Agreeableness and the PANSS insight item. Core traits of personality and dimensions of interpersonal problems are associated with both patients' and therapists' perceptions of the quality of the working alliance. Copyright © 2013 Elsevier Inc. All rights reserved.
Zebrak, Katarzyna A; Green, Kerry M
2017-11-01
African Americans are disproportionately affected by HIV/AIDS and other sexually transmitted infections relative to other racial groups. Although substance use has been linked to risky sexual behavior, the understanding of how these associations develop over the life course remains limited, particularly the role of social bonds. This study uses structural equation modeling to examine pathways from adolescent substance use to young adult sexual risk, substance problems, and social bonds and then to midlife risky sexual behavior among African American men and women, controlling for childhood confounders. Data come from 4 assessments, 1 per developmental period, of a community-based urban African American cohort (N = 1,242) followed prospectively from ages 6 to 42 years. We found that greater adolescent substance use predicts greater young adult substance problems and increased risky sexual behavior, both of which in turn predict greater midlife sexual risk. Although greater adolescent substance use predicts fewer young adult social bonds for both genders, less young adult social bonding is unexpectedly associated with decreased midlife risky sexual behavior among women and not related for men. Substance use interventions among urban African American adolescents may have both immediate and long-term effects on decreasing sexual risk behaviors. Given the association between young adult social bonding and midlife risky sex among females, number of social bonds should not be used as a criterion for determining whom to screen for sexual risk among African American women. Future studies should explore other aspects of social bonding in linking substance use and risky sexual behavior over time. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Nader-Grosbois, Nathalie; Houssa, Marine; Mazzone, Stéphanie
2013-09-01
This study compared Theory of Mind (ToM) emotion and belief abilities in 43 children with externalized behavior (EB) disorders presenting low intelligence, 40 children with intellectual disabilities (ID) and 33 typically developing (TD) preschoolers (as a control group), matched for developmental age. The links between their ToM abilities, their level in seven self-regulation strategies as displayed in social problem-solving tasks and their social adjustment profiles (assessed by the Social Competence and Behavior Evaluation, completed by their teachers) were examined. Children with EB presented lower comprehension of causes of emotions and lower self-regulation of joint attention and of attention than children with ID and TD children. In comparison with TD children, lower social adjustment was observed in nearly all dimensions of profiles in both atypical groups. Specifically, children with EB were significantly angrier than children with ID. Although variable patterns of positive correlations were obtained in atypical groups between self-regulation strategies and ToM abilities, the most numerous positive links were obtained in the group with EB. Regression analyses showed that developmental age predicted ToM abilities and certain dimensions of social adjustment profiles in atypical groups. In the ID group, ToM emotions predicted general adaptation, affective adaptation, interactions with peers and with adults and low internalizing problems. In the EB group, general adaptation was predicted by ToM emotions and self-regulation, interactions with peers by ToM beliefs, and a low level of externalizing problems by ToM emotions. Some implications for intervention and perspectives for research are suggested. Copyright © 2013 Elsevier Ltd. All rights reserved.
The random fractional matching problem
NASA Astrophysics Data System (ADS)
Lucibello, Carlo; Malatesta, Enrico M.; Parisi, Giorgio; Sicuro, Gabriele
2018-05-01
We consider two formulations of the random-link fractional matching problem, a relaxed version of the more standard random-link (integer) matching problem. In one formulation, we allow each node to be linked to itself in the optimal matching configuration. In the other one, on the contrary, such a link is forbidden. Both problems have the same asymptotic average optimal cost of the random-link matching problem on the complete graph. Using a replica approach and previous results of Wästlund (2010 Acta Mathematica 204 91–150), we analytically derive the finite-size corrections to the asymptotic optimal cost. We compare our results with numerical simulations and we discuss the main differences between random-link fractional matching problems and the random-link matching problem.
Enhanced method of fast re-routing with load balancing in software-defined networks
NASA Astrophysics Data System (ADS)
Lemeshko, Oleksandr; Yeremenko, Oleksandra
2017-11-01
A two-level method of fast re-routing with load balancing in a software-defined network (SDN) is proposed. The novelty of the method consists, firstly, in the introduction of a two-level hierarchy of calculating the routing variables responsible for the formation of the primary and backup paths, and secondly, in ensuring a balanced load of the communication links of the network, which meets the requirements of the traffic engineering concept. The method provides implementation of link, node, path, and bandwidth protection schemes for fast re-routing in SDN. The separation in accordance with the interaction prediction principle along two hierarchical levels of the calculation functions of the primary (lower level) and backup (upper level) routes allowed to abandon the initial sufficiently large and nonlinear optimization problem by transiting to the iterative solution of linear optimization problems of half the dimension. The analysis of the proposed method confirmed its efficiency and effectiveness in terms of obtaining optimal solutions for ensuring balanced load of communication links and implementing the required network element protection schemes for fast re-routing in SDN.
An evidential link prediction method and link predictability based on Shannon entropy
NASA Astrophysics Data System (ADS)
Yin, Likang; Zheng, Haoyang; Bian, Tian; Deng, Yong
2017-09-01
Predicting missing links is of both theoretical value and practical interest in network science. In this paper, we empirically investigate a new link prediction method base on similarity and compare nine well-known local similarity measures on nine real networks. Most of the previous studies focus on the accuracy, however, it is crucial to consider the link predictability as an initial property of networks itself. Hence, this paper has proposed a new link prediction approach called evidential measure (EM) based on Dempster-Shafer theory. Moreover, this paper proposed a new method to measure link predictability via local information and Shannon entropy.
NASA Astrophysics Data System (ADS)
Alvarado-Bonilla, Joel
The rising costs of fuels and specifically gasoline pose an economic challenge to U.S. consumers. Thus, the specific problem considered in this study was a rise in gasoline prices can reduce consumer spending, disposable income, food service traffic, and spending on healthy food, medicines, or visits to the doctor. Aligned with the problem, the purpose of this quantitative multiple correlation study was to examine the economic aspects for a rise in gasoline prices to reduce the six elements in the problem. This study consisted of a correlational design based on a retrospective longitudinal analysis (RLA) to examine gasoline prices versus the economic indexes of: (a) Retail Spending and (b) personal savings (PS). The RLA consisted on historic archival public data from 1978 to 2015. This RLA involved two separate linear multiple regression analyses to measure gasoline price's predictive power (PP) on two indexes while controlling for Unemployment Rate (UR). In summary, regression Formula 1 revealed Gasoline Price had a significant 61.1% PP on Retail Spending. In contrast, Formula 2 had Gasoline Price not having a significant PP on PS. Formula 2 yielded UR with 38.8% PP on PS. Results were significant at p<.01. Gasoline Price's PP on Retail Spending means a spending link to retail items such as: food service traffic, healthy food, medicines, and consumer spending. The UR predictive power on PS was unexpected, but logical from an economic view. Also unexpected was Gasoline Price's non-predictive power on PS, which suggests Americans may not save money when gasoline prices drop. These results shed light on the link of gasoline and UR on U.S. consumer's economy through savings and spending, which can be useful for policy design on gasoline and fuels taxing and pricing. The results serve as a basis for future study on gasoline and economics.
Specifying the Links Between Household Chaos and Preschool Children’s Development
Martin, Anne; Razza, Rachel; Brooks-Gunn, Jeanne
2011-01-01
Household chaos has been linked to poorer cognitive, behavioral, and self-regulatory outcomes in young children, but the mechanisms responsible remain largely unknown. Using a diverse sample of families in Chicago, the present study tests for the independent contributions made by five indicators of household chaos: noise, crowding, family instability, lack of routine, and television usually on. Chaos was measured at age 2; outcomes measured at age 5 tap receptive vocabulary, attention and behavior problems, and effortful control. Results show that controlling for all other measures of chaos, children with a lack of routine scored lower on receptive vocabulary and delayed gratification, while children whose television was generally on scored higher on aggression and attention problems. The provision of learning materials mediated a small part of the association between television and receptive vocabulary. Family instability, crowding, and noise did not predict any outcomes once other measures of chaos were controlled. PMID:22919120
Modecki, Kathryn L; Barber, Bonnie L; Vernon, Lynette; Vernon, Lynnette
2013-05-01
Technologically mediated contexts are social arenas in which adolescents can be both perpetrators and victims of aggression. Yet, there remains little understanding of the developmental etiology of cyber aggression, itself, as experienced by either perpetrators or victims. The current study examines 3-year latent within-person trajectories of known correlates of cyber-aggression: problem behavior, (low) self-esteem, and depressed mood, in a large and diverse sample of youth (N = 1,364; 54.6% female; 12-14 years old at T1). Findings demonstrate that developmental increases in problem behavior across grades 8-10 predict both cyber-perpetration and victimization in grade 11. Developmental decreases in self-esteem also predicted both grade 11 perpetration and victimization. Finally, early depressed mood predicted both perpetration and victimization later on, regardless of developmental change in depressed mood in the interim. Our results reveal a clear link between risky developmental trajectories across the early high school years and later cyber-aggression and imply that mitigating trajectories of risk early on may lead to decreases in cyber-aggression at a later date.
Gambler's ruin problem on Erdős-Rényi graphs
NASA Astrophysics Data System (ADS)
Néda, Zoltán; Davidova, Larissa; Újvári, Szeréna; Istrate, Gabriel
2017-02-01
A multiagent ruin-game is studied on Erdős-Rényi type graphs. Initially the players have the same wealth. At each time step a monopolist game is played on all active links (links that connect nodes with nonzero wealth). In such a game each player puts a unit wealth in the pot and the pot is won with equal probability by one of the players. The game ends when there are no connected players such that both of them have non-zero wealth. In order to characterize the final state for dense graphs a compact formula is given for the expected number of the remaining players with non-zero wealth and the wealth distribution among these players. Theoretical predictions are given for the expected duration of the ruin game. The dynamics of the number of active players is also investigated. Validity of the theoretical predictions is investigated by Monte Carlo experiments.
Predicting the Retention Behavior of Specific O-Linked Glycopeptides.
Badgett, Majors J; Boyes, Barry; Orlando, Ron
2017-09-01
O -Linked glycosylation is a common post-translational modification that can alter the overall structure, polarity, and function of proteins. Reverse-phase (RP) chromatography is the most common chromatographic approach to analyze O -glycosylated peptides and their unmodified counterparts, even though this approach often does not provide adequate separation of these two species. Hydrophilic interaction liquid chromatography (HILIC) can be a solution to this problem, as the polar glycan interacts with the polar stationary phase and potentially offers the ability to resolve the peptide from its modified form(s). In this paper, HILIC is used to separate peptides with O - N -acetylgalactosamine ( O -GalNAc), O - N -acetylglucosamine ( O -GlcNAc), and O -fucose additions from their native forms, and coefficients representing the extent of hydrophilicity were derived using linear regression analysis as a means to predict the retention times of peptides with these modifications.
Predicting the Retention Behavior of Specific O-Linked Glycopeptides
Badgett, Majors J.; Boyes, Barry; Orlando, Ron
2017-01-01
O-Linked glycosylation is a common post-translational modification that can alter the overall structure, polarity, and function of proteins. Reverse-phase (RP) chromatography is the most common chromatographic approach to analyze O-glycosylated peptides and their unmodified counterparts, even though this approach often does not provide adequate separation of these two species. Hydrophilic interaction liquid chromatography (HILIC) can be a solution to this problem, as the polar glycan interacts with the polar stationary phase and potentially offers the ability to resolve the peptide from its modified form(s). In this paper, HILIC is used to separate peptides with O-N-acetylgalactosamine (O-GalNAc), O-N-acetylglucosamine (O-GlcNAc), and O-fucose additions from their native forms, and coefficients representing the extent of hydrophilicity were derived using linear regression analysis as a means to predict the retention times of peptides with these modifications. PMID:28785176
Rosen, Craig S; Matthieu, Monica M; Norris, Fran H
2009-05-01
An important aspect of crisis counseling is linking survivors with services for their unmet needs. We examined determinants of referrals for disaster relief, additional crisis counseling, and psychological services in 703,000 crisis counseling encounters 3-18 months after Hurricane Katrina. Referrals for disaster relief were predicted by clients' losses, age (adults rather than children), and urbanicity. Referrals for additional counseling and psychological services were predicted by urbanicity, losses and trauma exposure, prior trauma, and preexisting mental health problems. Counseling and psychological referrals declined over time despite continuing mental health needs. Results confirm large urban-rural disparities in access to services.
Enhanced Predictive Handover for Fast Proxy Mobile IPv6
NASA Astrophysics Data System (ADS)
Jeon, Seil; Kang, Namhi; Kim, Younghan
Proxy Mobile IPv6 (PMIPv6) has been proposed in order to overcome the limitations of host-based mobility management in IPv6 networks. However, packet losses during doing handover are still a problem. To solve this issue, several schemes have been developed, and can be classified into two approaches: predictive and reactive handover. Both approaches commonly use bi-directional tunnel between mobile access gateways (MAGs). In predictive schemes especially, mobility support for a mobile node (MN) is triggered by simplified link signal strength. Thereafter, the MN sends handover notification to its serving MAG, and is then able to initiate packet forwarding. Therefore, if the MN moves toward an unexpected MAG that does not have any pre-established tunnel with the serving MAG, it may lead to packet losses. In this paper, we define this problem as Early Packet Forwarding (EPF). As a solution, we propose an enhanced PMIPv6 scheme using two-phase tunnel control based on the IEEE 802.21 Media Independent Handover (MIH).
Tschentscher, Nadja; Mitchell, Daniel; Duncan, John
2017-05-03
Fluid intelligence has been associated with a distributed cognitive control or multiple-demand (MD) network, comprising regions of lateral frontal, insular, dorsomedial frontal, and parietal cortex. Human fluid intelligence is also intimately linked to task complexity, and the process of solving complex problems in a sequence of simpler, more focused parts. Here, a complex target detection task included multiple independent rules, applied one at a time in successive task epochs. Although only one rule was applied at a time, increasing task complexity (i.e., the number of rules) impaired performance in participants of lower fluid intelligence. Accompanying this loss of performance was reduced response to rule-critical events across the distributed MD network. The results link fluid intelligence and MD function to a process of attentional focus on the successive parts of complex behavior. SIGNIFICANCE STATEMENT Fluid intelligence is intimately linked to the ability to structure complex problems in a sequence of simpler, more focused parts. We examine the basis for this link in the functions of a distributed frontoparietal or multiple-demand (MD) network. With increased task complexity, participants of lower fluid intelligence showed reduced responses to task-critical events. Reduced responses in the MD system were accompanied by impaired behavioral performance. Low fluid intelligence is linked to poor foregrounding of task-critical information across a distributed MD system. Copyright © 2017 Tschentscher et al.
Hatano, Kai; Sugimura, Kazumi; Schwartz, Seth J
2018-04-01
Most previous identity research has focused on relationships between identity synthesis, confusion, and psychosocial problems. However, these studies did not take into account Erikson's notion of identity consolidation, that is, the dynamic interplay between identity synthesis and confusion. This study aimed to examine longitudinal relationships and the directionality of the effects between identity consolidation and psychosocial problems during adolescence, using two waves of longitudinal data from 793 Japanese adolescents (49.7% girls; ages 13-14 and 16-17 at Time 1). A bi-factor latent change model revealed that levels and changes in identity consolidation were negatively associated with levels and changes in psychosocial problems. Furthermore, a bi-factor cross-lagged effects model provided evidence that identity consolidation negatively predicted psychosocial problems, and vice versa. Our study facilitates a better understanding of the importance of identity consolidation in the relations between identity components and psychosocial problems.
Behavioral flexibility and problem solving in an invasive bird.
Logan, Corina J
2016-01-01
Behavioral flexibility is considered an important trait for adapting to environmental change, but it is unclear what it is, how it works, and whether it is a problem solving ability. I investigated behavioral flexibility and problem solving experimentally in great-tailed grackles, an invasive bird species and thus a likely candidate for possessing behavioral flexibility. Grackles demonstrated behavioral flexibility in two contexts, the Aesop's Fable paradigm and a color association test. Contrary to predictions, behavioral flexibility did not correlate across contexts. Four out of 6 grackles exhibited efficient problem solving abilities, but problem solving efficiency did not appear to be directly linked with behavioral flexibility. Problem solving speed also did not significantly correlate with reversal learning scores, indicating that faster learners were not the most flexible. These results reveal how little we know about behavioral flexibility, and provide an immense opportunity for future research to explore how individuals and species can use behavior to react to changing environments.
Skalická, Věra; Belsky, Jay; Stenseng, Frode; Wichstrøm, Lars
2015-01-01
In this Norwegian study, bidirectional relations between children's behavior problems and child-teacher conflict and closeness were examined, and the possibility of moderation of these associations by child-care group size was tested. Eight hundred and nineteen 4-year-old children were followed up in first grade. Results revealed reciprocal effects linking child-teacher conflict and behavior problems. Effects of child-teacher closeness on later behavior problems were moderated by group size: For children in small groups only (i.e., ≤ 15 children), greater closeness predicted reduced behavior problems in first grade. In consequence, stability of behavior problems was greater in larger than in smaller groups. Results are discussed in light of regulatory mechanisms and social learning theory, with possible implications for organization of child care. © 2015 The Authors. Child Development © 2015 Society for Research in Child Development, Inc.
What Ever Happened To The ‘Cool’ Kids? Long-Term Sequelae Of Early Adolescent Pseudomature Behavior
Allen, Joseph P.; Schad, Megan M.; Oudekerk, Barbara; Chango, Joanna
2014-01-01
Pseudomature behavior—ranging from minor delinquency to precocious romantic involvement—is widely viewed as a nearly normative feature of adolescence. When such behavior occurs early in adolescence, however, it was hypothesized to reflect a misguided overemphasis upon impressing peers and was considered likely to predict long-term adjustment problems. In a multi-method, multi-reporter study following a community sample of 184 adolescents from age 13 to 23, early adolescent pseudomature behavior was linked cross-sectionally to a heightened desire for peer popularity and to short-term success with peers. Longitudinal results, however, supported the study’s central hypothesis: Early adolescent pseudomature behavior predicted long-term difficulties in close relationships, as well as significant problems with alcohol and substance use, and elevated levels of criminal behavior. PMID:24919537
An auxiliary optimization method for complex public transit route network based on link prediction
NASA Astrophysics Data System (ADS)
Zhang, Lin; Lu, Jian; Yue, Xianfei; Zhou, Jialin; Li, Yunxuan; Wan, Qian
2018-02-01
Inspired by the missing (new) link prediction and the spurious existing link identification in link prediction theory, this paper establishes an auxiliary optimization method for public transit route network (PTRN) based on link prediction. First, link prediction applied to PTRN is described, and based on reviewing the previous studies, the summary indices set and its algorithms set are collected for the link prediction experiment. Second, through analyzing the topological properties of Jinan’s PTRN established by the Space R method, we found that this is a typical small-world network with a relatively large average clustering coefficient. This phenomenon indicates that the structural similarity-based link prediction will show a good performance in this network. Then, based on the link prediction experiment of the summary indices set, three indices with maximum accuracy are selected for auxiliary optimization of Jinan’s PTRN. Furthermore, these link prediction results show that the overall layout of Jinan’s PTRN is stable and orderly, except for a partial area that requires optimization and reconstruction. The above pattern conforms to the general pattern of the optimal development stage of PTRN in China. Finally, based on the missing (new) link prediction and the spurious existing link identification, we propose optimization schemes that can be used not only to optimize current PTRN but also to evaluate PTRN planning.
Perfectionism and Personality Disorders as Predictors of Symptoms and Interpersonal Problems.
Dimaggio, Giancarlo; Lysaker, Paul H; Calarco, Teresa; Pedone, Roberto; Marsigli, Nicola; Riccardi, Ilaria; Sabatelli, Beatrice; Carcione, Antonino; Paviglianiti, Alessandra
2015-01-01
Maladaptive perfectionism is a common factor in many disorders and is correlated with some personality dysfunctions. Less clear is how dimensions, such as concern over mistakes, doubts about actions, and parental criticism, are linked to overall suffering. Additionally, correlations between perfectionism and personality disorders are poorly explored in clinical samples. In this study we compared a treatment seeking individuals (n=93) and a community sample (n=100) on dimensions of maladaptive perfectionism, personality disorders, symptoms, and interpersonal problems. Results in both samples revealed maladaptive perfectionism was strongly associated with general suffering, interpersonal problems, and a broad range of personality disordered traits. Excessive concern over one's errors, and to some extent doubts about actions, predicted unique additional variance beyond the presence of personality pathology in explaining symptoms and interpersonal problems.
Chmielewski, Witold X; Roessner, Veit; Beste, Christian
2015-10-01
The ability to link contextual information to actions is an important aspect of conflict monitoring and response selection. These mechanisms depend on medial prefrontal networks. Although these areas undergo a protracted development from adolescence to adulthood, it has remained elusive how the influence of contextual information on conflict monitoring is modulated between adolescence and adulthood. Using event-related potentials (ERPs) and source localization techniques we show that the ability to link contextual information to actions is altered and that the predictability of upcoming events is an important factor to consider in this context. In adolescents, conflict monitoring functions are not as much modulated by predictability factors as in adults. It seems that adults exhibit a stronger anticipation of upcoming events than adolescents. This results in disadvantages for adults when the upcoming context is not predictable. In adolescents, problems to predict upcoming events therefore turn out to be beneficial. Two cognitive-neurophysiological factors are important for this: The first factor is related to altered conflict monitoring functions associated with modulations of neural activity in the medial frontal cortex. The second factor is related to altered perceptual processing of target stimuli associated with modulations of neural activity in parieto-occipital areas. Copyright © 2015 Elsevier B.V. All rights reserved.
Reuben, Julia D; Shaw, Daniel S; Neiderhiser, Jenae M; Natsuaki, Misaki N; Reiss, David; Leve, Leslie D
2016-08-01
Externalizing symptoms, such as aggression, impulsivity, and inattention, represent the most common forms of childhood maladjustment (Campbell et al. Development and Psychopathology, 12, 467-488, 2000). Several dimensions of parenting behavior, including overreactive and warm parenting, have been linked to children's conduct problems. However, the majority of these studies involve biologically-related family members, thereby limiting understanding of the role of genetic and/or environmental underpinnings of parenting on child psychopathology. This study extends previous research by exploring associations between overreactive and warm parenting during toddlerhood and school-age externalizing problems, as well as the potential moderating effects of child effortful control (EC) on such associations using a longitudinal adoption design. The sample consisted of 225 adoption-linked families (adoptive parents, adopted child [124 male and 101 female] and birth parent[s]), thereby allowing for a more precise estimate of environmental influences on the association between parenting and child externalizing problems. Adoptive mothers' warm parenting at 27 months predicted lower levels of child externalizing problems at ages 6 and 7. Child EC moderated this association in relation to teacher reports of school-age externalizing problems. Findings corroborate prior research with biological families that was not designed to unpack genetic and environmental influences on associations between parenting and child externalizing problems during childhood, highlighting the important role of parental warmth as an environmental influence.
Reuben, Julia D.; Shaw, Daniel S.; Neiderhiser, Jenae M.; Natsuaki, Misaki N.; Reiss, David; Leve, Leslie D.
2016-01-01
Externalizing symptoms, such as aggression, impulsivity, and inattention, represent the most common forms of childhood maladjustment (Campbell, Shaw, & Gilliom, 2000). Several dimensions of parenting behavior, including overreactive and warm parenting, have been linked to children’s conduct problems. However, the majority of these studies involve biologically-related family members, thereby limiting understanding of the role of genetic and/or environmental underpinnings of parenting on child psychopathology. This study extends previous research by exploring associations between overreactive and warm parenting during toddlerhood and school-age externalizing problems, as well as the potential moderating effects of child effortful control (EC) on such associations using a longitudinal adoption design. The sample consisted of 225 adoption-linked families (adoptive parents, adopted child [124 male and 101 female] and birth parent[s]), thereby allowing for a more precise estimate of environmental influences on the association between parenting and child externalizing problems. Adoptive mothers’ warm parenting at 27 months predicted lower levels of child externalizing problems at ages 6 and 7. Child EC moderated this association in relation to teacher reports of school-age externalizing problems. Findings corroborate prior research with biological families that was not designed to unpack genetic and environmental influences on associations between parenting and child externalizing problems during childhood, highlighting the important role of parental warmth as an environmental influence. PMID:26496906
The construct-behavior gap in behavioral decision research: A challenge beyond replicability.
Regenwetter, Michel; Robinson, Maria M
2017-10-01
Behavioral decision research compares theoretical constructs like preferences to behavior such as observed choices. Three fairly common links from constructs to behavior are (1) to tally, across participants and decision problems, the number of choices consistent with one predicted pattern of pairwise preferences; (2) to compare what most people choose in each decision problem against a predicted preference pattern; or (3) to enumerate the decision problems in which two experimental conditions generate a 1-sided significant difference in choice frequency 'consistent' with the theory. Although simple, these theoretical links are heuristics. They are subject to well-known reasoning fallacies, most notably the fallacy of sweeping generalization and the fallacy of composition. No amount of replication can alleviate these fallacies. On the contrary, reiterating logically inconsistent theoretical reasoning over and again across studies obfuscates science. As a case in point, we consider pairwise choices among simple lotteries and the hypotheses of overweighting or underweighting of small probabilities, as well as the description-experience gap. We discuss ways to avoid reasoning fallacies in bridging the conceptual gap between hypothetical constructs, such as, for example, "overweighting" to observable pairwise choice data. Although replication is invaluable, successful replication of hard-to-interpret results is not. Behavioral decision research stands to gain much theoretical and empirical clarity by spelling out precise and formally explicit theories of how hypothetical constructs translate into observable behavior. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Improving Predictions of Multiple Binary Models in ILP
2014-01-01
Despite the success of ILP systems in learning first-order rules from small number of examples and complexly structured data in various domains, they struggle in dealing with multiclass problems. In most cases they boil down a multiclass problem into multiple black-box binary problems following the one-versus-one or one-versus-rest binarisation techniques and learn a theory for each one. When evaluating the learned theories of multiple class problems in one-versus-rest paradigm particularly, there is a bias caused by the default rule toward the negative classes leading to an unrealistic high performance beside the lack of prediction integrity between the theories. Here we discuss the problem of using one-versus-rest binarisation technique when it comes to evaluating multiclass data and propose several methods to remedy this problem. We also illustrate the methods and highlight their link to binary tree and Formal Concept Analysis (FCA). Our methods allow learning of a simple, consistent, and reliable multiclass theory by combining the rules of the multiple one-versus-rest theories into one rule list or rule set theory. Empirical evaluation over a number of data sets shows that our proposed methods produce coherent and accurate rule models from the rules learned by the ILP system of Aleph. PMID:24696657
Weiss, Nicole H; Bold, Krysten W; Sullivan, Tami P; Armeli, Stephen; Tennen, Howard
2017-04-01
Alcohol and marijuana are widely used among college students. Emotion regulation strategies have been linked to alcohol and marijuana use, but little attention has been devoted to modeling the directionality of these associations. The aims of the current study were to test whether (a) daytime use of emotion regulation strategies influences the likelihood of evening substance use and (b) evening substance use influences the likelihood of next-day use of emotion regulation strategies. Longitudinal daily diary data were collected for 30 days via on-line surveys. Northeastern United States. A total of 1640 college students (mean age = 19.2 years, 54% female, 80% European American) were recruited each semester between Spring 2008 and Spring 2012. Daily diaries assessed emotion regulation strategies (distraction, reappraisal, problem-solving, avoidance) and substance use (any drinking, heavy drinking, marijuana use, co-use of any drinking/heavy drinking and marijuana). Covariates included gender, age, race/ethnicity, fraternity/sorority involvement and baseline depression. Daytime distraction [odds ratio (OR) = 0.95], reappraisal (OR = 0.95) and problem-solving (OR = 0.94) predicted lower odds of evening marijuana use (P-values < 0.02). Evening heavy drinking (OR = 0.90) and marijuana use (OR = 0.89) predicted lower odds of next-day problem-solving, with heavy drinking also predicting higher odds (OR = 1.08) of next-day avoidance and marijuana use also predicting higher odds (OR = 1.08) of next-day reappraisal (P-values < 0.03). There appear to be reciprocal relations among emotion regulation strategies and substance use: greater daytime use of distraction, reappraisal, and problem solving predicts lower evening substance use, while higher evening substance use predicts higher next-day avoidance and reappraisal but lower next-day problem-solving. © 2016 Society for the Study of Addiction.
Predicting links based on knowledge dissemination in complex network
NASA Astrophysics Data System (ADS)
Zhou, Wen; Jia, Yifan
2017-04-01
Link prediction is the task of mining the missing links in networks or predicting the next vertex pair to be connected by a link. A lot of link prediction methods were inspired by evolutionary processes of networks. In this paper, a new mechanism for the formation of complex networks called knowledge dissemination (KD) is proposed with the assumption of knowledge disseminating through the paths of a network. Accordingly, a new link prediction method-knowledge dissemination based link prediction (KDLP)-is proposed to test KD. KDLP characterizes vertex similarity based on knowledge quantity (KQ) which measures the importance of a vertex through H-index. Extensive numerical simulations on six real-world networks demonstrate that KDLP is a strong link prediction method which performs at a higher prediction accuracy than four well-known similarity measures including common neighbors, local path index, average commute time and matrix forest index. Furthermore, based on the common conclusion that an excellent link prediction method reveals a good evolving mechanism, the experiment results suggest that KD is a considerable network evolving mechanism for the formation of complex networks.
Hogue, Aaron; Dauber, Sarah; Samuolis, Jessica; Liddle, Howard A.
2010-01-01
The link between treatment techniques and long-term treatment outcome was examined in an empirically supported family-based treatment for adolescent drug abuse. Observational ratings of therapist interventions were used to predict outcomes at 6 and 12 months posttreatment for 63 families receiving multidimensional family therapy. Greater use of in-session family-focused techniques predicted reduction in internalizing symptoms and improvement in family cohesion. Greater use of family-focused techniques also predicted reduced externalizing symptoms and family conflict, but only when adolescent focus was also high. In addition, greater use of adolescent-focused techniques predicted improvement in family cohesion and family conflict. Results suggest that both individual and multiperson interventions can exert an influential role in family-based therapy for clinically referred adolescents. PMID:17176187
Nilsen, Wendy; Gustavson, Kristin; Røysamb, Espen; Kjeldsen, Anne; Karevold, Evalill
2013-06-01
The main aim of this study was to identify the pathways from maternal distress and child problem behaviors (i.e., internalizing and externalizing problems) across childhood and their impact on depressive symptoms during adolescence among girls and boys. Data from families of 921 Norwegian children in a 15-year longitudinal community sample were used. Using structural equation modeling, the authors explored the interplay between maternal-reported distress and child problem behaviors measured at 5 time points from early (ages 1.5, 2.5, and 4.5 years) and middle (age 8.5 years) childhood to early adolescence (age 12.5 years), and their prediction of self-reported depressive symptoms during adolescence (ages 14.5 and 16.5 years). The findings revealed paths from internalizing and externalizing problems throughout the development for corresponding problems (homotypic paths) and paths from early externalizing to subsequent internalizing problems (heterotypic paths). The findings suggest 2 pathways linking maternal-rated risk factors to self-reported adolescent depressive symptoms. There was a direct path from early externalizing problems to depressive symptoms. There was an indirect path from early maternal distress going through child problem behavior to depressive symptoms. In general, girls and boys were similar, but some gender-specific effects appeared. Problem behaviors in middle childhood had heterotypic paths to subsequent problems only for girls. The findings highlight the developmental importance of child externalizing problems, as well as the impact of maternal distress as early as age 1.5 years for the development of adolescent depressive symptoms. Findings also indicate a certain vulnerable period in middle childhood for girls. NOTE: See Supplemental Digital Content 1, at http://links.lww.com/JDBP/A45, for a video introduction to this article.
Grossberg, Stephen
2017-03-01
The hard problem of consciousness is the problem of explaining how we experience qualia or phenomenal experiences, such as seeing, hearing, and feeling, and knowing what they are. To solve this problem, a theory of consciousness needs to link brain to mind by modeling how emergent properties of several brain mechanisms interacting together embody detailed properties of individual conscious psychological experiences. This article summarizes evidence that Adaptive Resonance Theory, or ART, accomplishes this goal. ART is a cognitive and neural theory of how advanced brains autonomously learn to attend, recognize, and predict objects and events in a changing world. ART has predicted that "all conscious states are resonant states" as part of its specification of mechanistic links between processes of consciousness, learning, expectation, attention, resonance, and synchrony. It hereby provides functional and mechanistic explanations of data ranging from individual spikes and their synchronization to the dynamics of conscious perceptual, cognitive, and cognitive-emotional experiences. ART has reached sufficient maturity to begin classifying the brain resonances that support conscious experiences of seeing, hearing, feeling, and knowing. Psychological and neurobiological data in both normal individuals and clinical patients are clarified by this classification. This analysis also explains why not all resonances become conscious, and why not all brain dynamics are resonant. The global organization of the brain into computationally complementary cortical processing streams (complementary computing), and the organization of the cerebral cortex into characteristic layers of cells (laminar computing), figure prominently in these explanations of conscious and unconscious processes. Alternative models of consciousness are also discussed. Copyright © 2016 The Author. Published by Elsevier Ltd.. All rights reserved.
Links between sleep and daytime behaviour problems in children with Down syndrome.
Esbensen, A J; Hoffman, E K; Beebe, D W; Byars, K C; Epstein, J
2018-02-01
In the general population, sleep problems have an impact on daytime performance. Despite sleep problems being common among children with Down syndrome, the impact of sleep problems on daytime behaviours in school-age children with Down syndrome is an understudied topic. Our study examined the relationship between parent-reported and actigraphy-measured sleep duration and sleep quality with parent and teacher reports of daytime behaviour problems among school-age children with Down syndrome. Thirty school-age children with Down syndrome wore an actigraph watch for a week at home at night. Their parent completed ratings of the child's sleep during that same week. Their parent and teacher completed a battery of measures to assess daytime behaviour. Parent reports of restless sleep behaviours on the Children's Sleep Habits Questionnaire, but not actigraph-measured sleep efficiency, was predictive of parent and teacher behavioural concerns on the Nisonger Child Behaviour Rating Form and the Vanderbilt ADHD Rating Scales. Actigraph-measured sleep period and parent-reported sleep duration on the Children's Sleep Habits Questionnaire was predictive of daytime parent-reported inattention. Actigraph-measured sleep period was predictive of parent-reported hyperactivity/impulsivity. The study findings suggest that sleep problems have complex relationships to both parent-reported and teacher-reported daytime behaviour concerns in children with Down syndrome. These findings have implications for understanding the factors impacting behavioural concerns and their treatment in school-age children with Down syndrome. © 2017 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.
Rioux, Charlie; Castellanos-Ryan, Natalie; Parent, Sophie; Séguin, Jean R.
2016-01-01
Both individual and environmental factors predict externalizing behaviors and substance use (EB-SU); however, different patterns of interaction among these factors may have different implications. This review first examines how temperament and the family environment interact in the prediction of adolescent EB-SU. Second, studies are reviewed according to two theoretical models: (1) diathesis–stress, i.e., certain individual characteristics are linked to vulnerability and later problems in adverse environments; (2) differential susceptibility, i.e., these characteristics are linked to susceptibility, predicting problems in adverse environments, but also better than average outcomes in good environments. Fourteen studies focusing on the prediction of EB-SU at ages 12–18 were selected through a literature search. Results showed that certain temperament traits (high levels of impulsivity and disinhibition; low levels of effortful control, negative affect, fearfulness and shyness), hereby designated as “adventurous” disposition, were associated with higher levels of EB-SU in adverse family environments. Some studies also showed that children with “adventurous” temperament traits in positive environments had the lowest levels of EB-SU. This suggests that prevention of EB-SU might target family factors such as parenting and focus on children with “adventurous” temperament traits. Further, studies that supported the differential susceptibility model were those assessing temperament and the family environment in childhood and studies that supported the diathesis–stress model assessed these variables in adolescence. It is thus possible that some of these “adventurous” temperament traits, with regard to EB-SU, would be indicators of susceptibility to both enriched and adverse environments in childhood but no longer in adolescence, when they would only be indicators of vulnerability to adverse environments. PMID:27413247
Parenting Practices and Child Disruptive Behavior Problems in Early Elementary School
Stormshak, Elizabeth A.; Bierman, Karen L.; McMahon, Robert J.; Lengua, Liliana J.
2009-01-01
Examined the hypothesis that distinct parenting practices may be associated with type and profile of a child’s disruptive behavior problems (e.g., oppositional, aggressive, hyperactive). Parents of 631 behaviorally disruptive children described the extent to which they experienced warm and involved interactions with their children and the extent to which their discipline strategies were inconsistent and punitive and involved spanking and physical aggression. As expected from a developmental perspective, parenting practices that included punitive interactions were associated with elevated rates of all child disruptive behavior problems. Low levels of warm involvement were particularly characteristic of parents of children who showed elevated levels of oppositional behaviors. Physically aggressive parenting was linked more specifically with child aggression. In general, parenting practices contributed more to the prediction of oppositional and aggressive behavior problems than to hyperactive behavior problems, and parenting influences were fairly consistent across ethnic groups and sex. PMID:10693029
Marino, Claudia; Moss, Antony C; Vieno, Alessio; Albery, Ian P; Frings, Daniel; Spada, Marcantonio M
2018-09-01
The aim of the current study was to test the direct and indirect influence of parents' drinking motives and problem drinking on their children's drinking motives, alcohol use and substance misuse. Cross-sectional analysis of parent and child drinking patterns and motives, derived from the nationally representative Drinkaware Monitor panel survey. The sample comprised a total of 148 couples of parents and child. Path analysis revealed that children's alcohol use and substance misuse were influenced by their own drinking motives and parents' problem drinking. Parents' conformity motives were linked to their children's conformity motives. Finally, parental drinking problems mediated the effect of their coping motives on their childrens' alcohol use and substance misuse. In conclusion, parental drinking styles relate to their children's alcohol use and substance misuse through problem drinking and drinking motives. Copyright © 2018 Elsevier Ltd. All rights reserved.
Bayesian neural adjustment of inhibitory control predicts emergence of problem stimulant use.
Harlé, Katia M; Stewart, Jennifer L; Zhang, Shunan; Tapert, Susan F; Yu, Angela J; Paulus, Martin P
2015-11-01
Bayesian ideal observer models quantify individuals' context- and experience-dependent beliefs and expectations about their environment, which provides a powerful approach (i) to link basic behavioural mechanisms to neural processing; and (ii) to generate clinical predictors for patient populations. Here, we focus on (ii) and determine whether individual differences in the neural representation of the need to stop in an inhibitory task can predict the development of problem use (i.e. abuse or dependence) in individuals experimenting with stimulants. One hundred and fifty-seven non-dependent occasional stimulant users, aged 18-24, completed a stop-signal task while undergoing functional magnetic resonance imaging. These individuals were prospectively followed for 3 years and evaluated for stimulant use and abuse/dependence symptoms. At follow-up, 38 occasional stimulant users met criteria for a stimulant use disorder (problem stimulant users), while 50 had discontinued use (desisted stimulant users). We found that those individuals who showed greater neural responses associated with Bayesian prediction errors, i.e. the difference between actual and expected need to stop on a given trial, in right medial prefrontal cortex/anterior cingulate cortex, caudate, anterior insula, and thalamus were more likely to exhibit problem use 3 years later. Importantly, these computationally based neural predictors outperformed clinical measures and non-model based neural variables in predicting clinical status. In conclusion, young adults who show exaggerated brain processing underlying whether to 'stop' or to 'go' are more likely to develop stimulant abuse. Thus, Bayesian cognitive models provide both a computational explanation and potential predictive biomarkers of belief processing deficits in individuals at risk for stimulant addiction. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Murray, Stuart B; Rieger, Elizabeth; Karlov, Lisa; Touyz, Stephen W
2013-03-01
Muscle dysmorphia is a psychiatric disorder that has been conceptually linked to eating disorders, although its precise nosology remains unclear. To further investigate this notion, the present study examined the applicability of the transdiagnostic model of eating disorders to muscle dysmorphia. One hundred and nineteen male undergraduate students completed self-report measures of multidimensional perfectionism, mood intolerance, self-esteem, interpersonal problems, and muscle dysmorphia symptomatology. Self-oriented perfectionism, socially prescribed perfectionism, mood intolerance, and low self-esteem significantly predicted muscle dysmorphia symptomatology, whereas other-oriented perfectionism and interpersonal problems did not demonstrate significant predictive value when accounting for the other transdiagnostic constructs. The transdiagnostic model of eating disorders may potentially be applied to enhance our understanding of the maintenance of muscle dysmorphic features in addition to eating disorder symptomatology. Copyright © 2012 John Wiley & Sons, Ltd and Eating Disorders Association.
Newton, Tamara L; Burns, Vicki Ellison; Miller, James J; Fernandez-Botran, G Rafael
2016-05-01
A marital status of divorced or separated, as opposed to married, predicts increased risk of health problems, but not for all persons. Focusing on one established health risk that has been linked with divorce--poor subjective sleep quality--the present cross-sectional study examined whether a history of physical intimate partner victimization (IPV) helps identify divorced women at potentially greater risk of health problems. Community midlife women with divorce histories, all of whom were free of current IPV, reported on their past month sleep quality and lifetime IPV. The predicted odds of poor sleep quality were significantly greater for women with, versus without, IPV histories. This held after adjusting for socioemotional, medical, or sociodemographic risks. A dose-response relationship between IPV chronicity and poor quality sleep was observed. IPV history may help identify divorced women at increased risk of poor quality sleep and, more broadly, poor health. © The Author(s) 2015.
On the joys of perceiving: Affect as feedback for perceptual predictions.
Chetverikov, Andrey; Kristjánsson, Árni
2016-09-01
How we perceive, attend to, or remember the stimuli in our environment depends on our preferences for them. Here we argue that this dependence is reciprocal: pleasures and displeasures are heavily dependent on cognitive processing, namely, on our ability to predict the world correctly. We propose that prediction errors, inversely weighted with prior probabilities of predictions, yield subjective experiences of positive or negative affect. In this way, we link affect to predictions within a predictive coding framework. We discuss how three key factors - uncertainty, expectations, and conflict - influence prediction accuracy and show how they shape our affective response. We demonstrate that predictable stimuli are, in general, preferred to unpredictable ones, though too much predictability may decrease this liking effect. Furthermore, the account successfully overcomes the "dark-room" problem, explaining why we do not avoid stimulation to minimize prediction error. We further discuss the implications of our approach for art perception and the utility of affect as feedback for predictions within a prediction-testing architecture of cognition. Copyright © 2016 Elsevier B.V. All rights reserved.
Jackowska, Marta; Poole, Lydia
2017-09-01
This study investigated whether sleep problems, sleep duration and a combination of short or long sleep with sleep problems were predictive of depressive symptoms six years later. Participants were 4545 men and women aged 50 years or older from the English Longitudinal Study of Ageing. Sleep problems were indexed through self-report enquiring about the most frequent insomnia symptoms including difficulties falling asleep, waking up several times a night and waking up in the morning feeling tired. Sleep duration was ascertained by asking about average sleep in the weeknight. Depressive symptoms were measured with the Center for Epidemiologic Studies Depression scale. Sleep problems were predictive of elevated depressive symptoms at follow-up (odds ratio [OR] = 1.36, 95% confidence interval [CI] = 1.19-1.56). When explored separately, waking up in the morning feeling tired (OR = 1.71, 95% CI = 1.24-2.37) followed by difficulties falling asleep (OR = 1.49, 95% CI = 1.06-2.11) were also predictors of future depressive symptoms. Compared to optimal duration, short (OR = 1.90, 95% CI = 1.34-2.71) but not long sleep hours were also linked to elevated depressive symptoms. Participants reporting short sleep hours combined with high sleep problems also had an elevated risk of depressive symptoms six years later (OR = 1.85, 95% CI = 1.15-3.00). Long sleep combined with high sleep problems was not predictive of depressive symptoms. Short and disturbed sleep and their combination increase the risk of future depressive symptoms in older adults. Copyright © 2017 Elsevier B.V. All rights reserved.
Emotion dysregulation and social competence: stability, change and predictive power.
Berkovits, L D; Baker, B L
2014-08-01
Social difficulties are closely linked to emotion dysregulation among children with typical development (TD). Children with developmental delays (DD) are at risk for poor social outcomes, but the relationship between social and emotional development within this population is not well understood. The current study examines the extent to which emotion dysregulation is related to social problems across middle childhood among children with TD or DD. Children with TD (IQ ≥ 85, n = 113) and children with DD (IQ ≤ 75, n = 61) participated in a longitudinal study. Annual assessments were completed at ages 7, 8 and 9 years. At each assessment, mothers reported on children's emotion dysregulation, and both mothers and teachers reported on children's social difficulties. Children with DD had higher levels of emotion dysregulation and social problems at each age than those with TD. Emotion dysregulation and social problems were significantly positively correlated within both TD and DD groups using mother report of social problems, and within the TD group using teacher report of social problems. Among children with TD, emotion dysregulation consistently predicted change in social problems from one year to the next. However, among children with DD, emotion dysregulation offered no unique prediction value above and beyond current social problems. Results suggested that the influence of emotion regulation abilities on social development may be a less salient pathway for children with DD. These children may have more influences, beyond emotion regulation, on their social behaviour, highlighting the importance of directly targeting social skill deficits among children with DD in order to ameliorate their social difficulties. © 2013 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.
Effectiveness of link prediction for face-to-face behavioral networks.
Tsugawa, Sho; Ohsaki, Hiroyuki
2013-01-01
Research on link prediction for social networks has been actively pursued. In link prediction for a given social network obtained from time-windowed observation, new link formation in the network is predicted from the topology of the obtained network. In contrast, recent advances in sensing technology have made it possible to obtain face-to-face behavioral networks, which are social networks representing face-to-face interactions among people. However, the effectiveness of link prediction techniques for face-to-face behavioral networks has not yet been explored in depth. To clarify this point, here we investigate the accuracy of conventional link prediction techniques for networks obtained from the history of face-to-face interactions among participants at an academic conference. Our findings were (1) that conventional link prediction techniques predict new link formation with a precision of 0.30-0.45 and a recall of 0.10-0.20, (2) that prolonged observation of social networks often degrades the prediction accuracy, (3) that the proposed decaying weight method leads to higher prediction accuracy than can be achieved by observing all records of communication and simply using them unmodified, and (4) that the prediction accuracy for face-to-face behavioral networks is relatively high compared to that for non-social networks, but not as high as for other types of social networks.
Community detection in complex networks using link prediction
NASA Astrophysics Data System (ADS)
Cheng, Hui-Min; Ning, Yi-Zi; Yin, Zhao; Yan, Chao; Liu, Xin; Zhang, Zhong-Yuan
2018-01-01
Community detection and link prediction are both of great significance in network analysis, which provide very valuable insights into topological structures of the network from different perspectives. In this paper, we propose a novel community detection algorithm with inclusion of link prediction, motivated by the question whether link prediction can be devoted to improving the accuracy of community partition. For link prediction, we propose two novel indices to compute the similarity between each pair of nodes, one of which aims to add missing links, and the other tries to remove spurious edges. Extensive experiments are conducted on benchmark data sets, and the results of our proposed algorithm are compared with two classes of baselines. In conclusion, our proposed algorithm is competitive, revealing that link prediction does improve the precision of community detection.
Burr, Hermann; Pedersen, Jacob; Hansen, Jørgen Vinsløv
2011-07-01
The present overview discusses ten papers dealing with four research topics using self-reported work environment in the Danish Work Environment Cohort Study (DWECS) linked with register data on long-term sickness absence (LTSA) in the Danish Register for Evaluation of Marginalisation (DREAM). Research relied on self-reported data among 3000-5000 employees linked with registered LTSA data. Analyses were performed with Cox regression models. Risk groups: Kindergarten teachers and daycare workers were at high risk for LTSA. Mainly physical exposures but also psychosocial factors were risk factors for LTSA. Attributable fractions: A quarter of LTSA spells could be attributed to the physical work environment. Most of the association between social class and LTSA was explained by physical work environment and smoking. Mechanisms: Depressive symptoms, severe pain in hands, and low back and pain intensity were risk factors for LTSA. Only in work sites with traditional leadership did health problems predict LTSA. The linking of DWECS with DREAM has made it possible to estimate the importance of work environment factors for LTSA. Future research should deal with possible risk factors such as health problems and organisational factors.
Is self-generated thought a means of social problem solving?
Ruby, Florence J. M.; Smallwood, Jonathan; Sackur, Jerome; Singer, Tania
2013-01-01
Appropriate social problem solving constitutes a critical skill for individuals and may rely on processes important for self-generated thought (SGT). The aim of the current study was to investigate the link between SGT and social problem solving. Using the Means-End Problem Solving task (MEPS), we assessed participants' abilities to resolve daily social problems in terms of overall efficiency and number of relevant means they provided to reach the given solution. Participants also performed a non-demanding choice reaction time task (CRT) and a moderately-demanding working memory task (WM) as a context in which to measure their SGT (assessed via thought sampling). We found that although overall SGT was associated with lower MEPS efficiency, it was also associated with higher relevant means, perhaps because both depend on the capacity to generate cognition that is independent from the hear and now. The specific content of SGT did not differentially predict individual differences in social problem solving, suggesting that the relationship may depend on SGT regardless of its content. In addition, we also found that performance at the WM but not the CRT was linked to overall better MEPS performance, suggesting that individuals good at social processing are also distinguished by their capacity to constrain attention to an external task. Our results provide novel evidence that the capacity for SGT is implicated in the process by which solutions to social problems are generated, although optimal problem solving may be achieved by individuals who display a suitable balance between SGT and cognition derived from perceptual input. PMID:24391621
Crash test for the Copenhagen problem.
Nagler, Jan
2004-06-01
The Copenhagen problem is a simple model in celestial mechanics. It serves to investigate the behavior of a small body under the gravitational influence of two equally heavy primary bodies. We present a partition of orbits into classes of various kinds of regular motion, chaotic motion, escape and crash. Collisions of the small body onto one of the primaries turn out to be unexpectedly frequent, and their probability displays a scale-free dependence on the size of the primaries. The analysis reveals a high degree of complexity so that long term prediction may become a formidable task. Moreover, we link the results to chaotic scattering theory and the theory of leaking Hamiltonian systems.
Norman, Laura M.
2007-01-01
Ecological considerations need to be interwoven with economic policy and planning along the United States‐Mexican border. Non‐point source pollution can have significant implications for the availability of potable water and the continued health of borderland ecosystems in arid lands. However, environmental assessments in this region present a host of unique issues and problems. A common obstacle to the solution of these problems is the integration of data with different resolutions, naming conventions, and quality to create a consistent database across the binational study area. This report presents a simple modeling approach to predict nonpoint source pollution that can be used for border watersheds. The modeling approach links a hillslopescale erosion‐prediction model and a spatially derived sediment‐delivery model within a geographic information system to estimate erosion, sediment yield, and sediment deposition across the Ambos Nogales watershed in Sonora, Mexico, and Arizona. This paper discusses the procedures used for creating a watershed database to apply the models and presents an example of the modeling approach applied to a conservation‐planning problem.
The Longitudinal Association Between Poor Sleep Quality and Cyberbullying, Mediated by Anger.
Erreygers, Sara; Vandebosch, Heidi; Vranjes, Ivana; Baillien, Elfi; De Witte, Hans
2018-01-09
Adolescents tend to go to bed later and sleep less as they grow older, although their need for sleep stays the same throughout adolescence. Poor sleep has negative consequences on personal and interpersonal functioning, including increased aggressive tendencies. With adolescents' social life increasingly including interactions via digital media, these interactions may also become more aggressive when adolescents' sleep problems increase. One of the ways in which online aggression may be enacted is through cyberbullying. Although previous research has examined the role of sleep disruptions in offline bullying, the role of sleep in cyberbullying has not yet been addressed. Therefore, this study examines the longitudinal effect of poor sleep quality on later cyberbullying behavior. Thirteen- to fourteen-year-old adolescents completed self-report measures on sleep quality, anger, cyberbullying perpetration, and frequency of digital media use. Because one of the pathways through which sleep is proposed to be linked to aggression is an affective pathway, namely via angry affect, a mediation model of poor sleep quality predicting cyberbullying via feelings of anger was tested. Results from structural equation modeling and a bootstrap test indicated that poor sleep quality was indeed indirectly associated with later cyberbullying behavior through heightened feelings of anger, even when taking the effects of the use of digital media and previous cyberbullying behavior into account. This finding provides support for the proposed affective pathway linking sleep problems to aggression. As sleep problems and anger seem to play a predicting role in cyberbullying behavior, suggestions for cyberbullying intervention and prevention strategies are formulated.
A hierarchical anatomical classification schema for prediction of phenotypic side effects
Kanji, Rakesh
2018-01-01
Prediction of adverse drug reactions is an important problem in drug discovery endeavors which can be addressed with data-driven strategies. SIDER is one of the most reliable and frequently used datasets for identification of key features as well as building machine learning models for side effects prediction. The inherently unbalanced nature of this data presents with a difficult multi-label multi-class problem towards prediction of drug side effects. We highlight the intrinsic issue with SIDER data and methodological flaws in relying on performance measures such as AUC while attempting to predict side effects.We argue for the use of metrics that are robust to class imbalance for evaluation of classifiers. Importantly, we present a ‘hierarchical anatomical classification schema’ which aggregates side effects into organs, sub-systems, and systems. With the help of a weighted performance measure, using 5-fold cross-validation we show that this strategy facilitates biologically meaningful side effects prediction at different levels of anatomical hierarchy. By implementing various machine learning classifiers we show that Random Forest model yields best classification accuracy at each level of coarse-graining. The manually curated, hierarchical schema for side effects can also serve as the basis of future studies towards prediction of adverse reactions and identification of key features linked to specific organ systems. Our study provides a strategy for hierarchical classification of side effects rooted in the anatomy and can pave the way for calibrated expert systems for multi-level prediction of side effects. PMID:29494708
A hierarchical anatomical classification schema for prediction of phenotypic side effects.
Wadhwa, Somin; Gupta, Aishwarya; Dokania, Shubham; Kanji, Rakesh; Bagler, Ganesh
2018-01-01
Prediction of adverse drug reactions is an important problem in drug discovery endeavors which can be addressed with data-driven strategies. SIDER is one of the most reliable and frequently used datasets for identification of key features as well as building machine learning models for side effects prediction. The inherently unbalanced nature of this data presents with a difficult multi-label multi-class problem towards prediction of drug side effects. We highlight the intrinsic issue with SIDER data and methodological flaws in relying on performance measures such as AUC while attempting to predict side effects.We argue for the use of metrics that are robust to class imbalance for evaluation of classifiers. Importantly, we present a 'hierarchical anatomical classification schema' which aggregates side effects into organs, sub-systems, and systems. With the help of a weighted performance measure, using 5-fold cross-validation we show that this strategy facilitates biologically meaningful side effects prediction at different levels of anatomical hierarchy. By implementing various machine learning classifiers we show that Random Forest model yields best classification accuracy at each level of coarse-graining. The manually curated, hierarchical schema for side effects can also serve as the basis of future studies towards prediction of adverse reactions and identification of key features linked to specific organ systems. Our study provides a strategy for hierarchical classification of side effects rooted in the anatomy and can pave the way for calibrated expert systems for multi-level prediction of side effects.
Effectiveness of Link Prediction for Face-to-Face Behavioral Networks
Tsugawa, Sho; Ohsaki, Hiroyuki
2013-01-01
Research on link prediction for social networks has been actively pursued. In link prediction for a given social network obtained from time-windowed observation, new link formation in the network is predicted from the topology of the obtained network. In contrast, recent advances in sensing technology have made it possible to obtain face-to-face behavioral networks, which are social networks representing face-to-face interactions among people. However, the effectiveness of link prediction techniques for face-to-face behavioral networks has not yet been explored in depth. To clarify this point, here we investigate the accuracy of conventional link prediction techniques for networks obtained from the history of face-to-face interactions among participants at an academic conference. Our findings were (1) that conventional link prediction techniques predict new link formation with a precision of 0.30–0.45 and a recall of 0.10–0.20, (2) that prolonged observation of social networks often degrades the prediction accuracy, (3) that the proposed decaying weight method leads to higher prediction accuracy than can be achieved by observing all records of communication and simply using them unmodified, and (4) that the prediction accuracy for face-to-face behavioral networks is relatively high compared to that for non-social networks, but not as high as for other types of social networks. PMID:24339956
Slade, P; O'Neill, C; Simpson, A J; Lashen, H
2007-08-01
A model suggesting that high perception of stigma is associated with reduced disclosure to others, leading to lower social support and higher distress in new attendees at an infertility clinic is tested. Questionnaires measuring stigmatization (Stigma consciousness questionnaire), disclosure of fertility difficulties (Disclosure questionnaire), social support (Duke-UNC Functional Social Support Questionnaire) and fertility-related [Fertility Problem Inventory (FPI)] and generic distress [Hospital Anxiety and Depression Scale (HADS)] were completed by 87 women and 64 men. Data were analysed by gender comparisons, correlations and path analysis. Women reported higher stigma and disclosure than men. For women, stigma and disclosure were unrelated but in men higher stigma was associated with lower disclosure. Perceptions of stigma were related to low social support for both genders. Social support was negatively related to anxiety, depression and overall infertility distress and showed greater predictive capacity than satisfaction with partner relationship. Testing the model showed that, for men, stigma was linked to lower disclosure and support and higher fertility-related and generic distress. Disclosure itself did not link to support. For women, greater disclosure linked only to higher generic distress. Stigma was directly linked to fertility-related distress and to low perceived support which mediated a relationship with generic distress. Stigma and the wider social context should be considered when supporting people with fertility problems. Greater disclosure may be associated with higher distress in women.
Natsuaki, Misaki N.; Ge, Xiaojia; Reiss, David; Neiderhiser, Jenae M.
2011-01-01
This study investigated the prospective links between sibling aggression and the development of externalizing problems using a multilevel modeling approach with a genetically sensitive design. The sample consisted of 780 adolescents (390 sibling pairs) who participated in two waves of the Nonshared Environment for Adolescent Development (NEAD) project. Sibling pairs with varying degree of genetic relatedness, including monozygotic twins, dizygotic twins, full siblings, half siblings, and genetically unrelated siblings, were included. The results showed that sibling aggression at Time 1 was significantly associated with the focal child’s externalizing problems at Time 2 after accounting for the intra-class correlations between siblings. Sibling aggression remained significant in predicting subsequent externalizing problems even after controlling for the levels of pre-existing externalizing problems and mothers’ punitive parenting. This pattern of results was fairly robust across models using different informants. The findings provide converging evidence for the unique contribution of sibling aggression in understanding changes in externalizing problems during adolescence. PMID:19586176
Behavioral flexibility and problem solving in an invasive bird
2016-01-01
Behavioral flexibility is considered an important trait for adapting to environmental change, but it is unclear what it is, how it works, and whether it is a problem solving ability. I investigated behavioral flexibility and problem solving experimentally in great-tailed grackles, an invasive bird species and thus a likely candidate for possessing behavioral flexibility. Grackles demonstrated behavioral flexibility in two contexts, the Aesop’s Fable paradigm and a color association test. Contrary to predictions, behavioral flexibility did not correlate across contexts. Four out of 6 grackles exhibited efficient problem solving abilities, but problem solving efficiency did not appear to be directly linked with behavioral flexibility. Problem solving speed also did not significantly correlate with reversal learning scores, indicating that faster learners were not the most flexible. These results reveal how little we know about behavioral flexibility, and provide an immense opportunity for future research to explore how individuals and species can use behavior to react to changing environments. PMID:27168984
Boeninger, Daria K.; Masyn, Katherine E.; Conger, Rand D.
2012-01-01
Although studies have established associations between parenting characteristics and adolescent suicidality, the strength of the evidence for these links remains unclear, largely because of methodological limitations, including lack of accounting for possible child effects on parenting. This study addresses these issues by using autoregressive cross-lag models with data on 802 adolescents and their parents across 5 years. Observed parenting behaviors predicted change in adolescent suicidal problems across one-year intervals even after controlling for adolescents’ effects on parenting. Nurturant-involved parenting continued to demonstrate salutary effects after controlling for adolescent and parent internalizing psychopathology: over time, observed nurturant-involved parenting reduced the likelihood of adolescent suicidal problems. This study increases the empirical support implicating parenting behaviors in the developmental course of adolescent suicidality. PMID:24244079
Low, Sabina M; Stocker, Clare
2005-09-01
Relations between parents' depressed mood, marital conflict, parent-child hostility, and children's adjustment were examined in a community sample of 136 ten-year-olds and their parents. Videotaped observational and self-report data were used to examine these relations in path analyses. A proposed model was tested in which mothers' and fathers' depressed mood and marital hostility were associated with children's adjustment problems through disruptions in parent-child relationships. Results showed that both mothers' and fathers' marital hostility were linked to parent-child hostility, which in turn was linked to children's internalizing problems. Fathers' depressed mood was linked to children's internalizing problems indirectly through father-child hostility. Fathers' depressed mood was directly linked to children's externalizing problems and indirectly linked through father-child hostility. For mothers, marital hostility was directly linked to children's externalizing problems, and marital hostility in fathers was indirectly linked to children's externalizing problems through father-child hostility. (c) 2005 APA, all rights reserved
Dysfunctional attitudes and poor problem solving skills predict hopelessness in major depression.
Cannon, B; Mulroy, R; Otto, M W; Rosenbaum, J F; Fava, M; Nierenberg, A A
1999-09-01
Hopelessness is a significant predictor of suicidality, but not all depressed patients feel hopeless. If clinicians can predict hopelessness, they may be able to identify those patients at risk of suicide and focus interventions on factors associated with hopelessness. In this study, we examined potential predictors of hopelessness in a sample of depressed outpatients. In this study, we examined potential demographic, diagnostic, and symptom predictors of hopelessness in a sample of 138 medication-free outpatients (73 women and 65 men) with a primary diagnosis of major depression. The significance of predictors was evaluated in both simple and multiple regression analyses. Consistent with previous studies, we found no significant associations between demographic and diagnostic variables and greater hopelessness. Hopelessness was significantly associated with greater depression severity, poor problem solving abilities as assessed by the Problem Solving Inventory, and each of two measures of dysfunctional cognitions (the Dysfunctional Attitudes Scale and the Cognitions Questionnaire). In a stepwise multiple regression equation, however, only dysfunctional cognitions and poor problem solving offered non-redundant prediction of hopelessness scores, and accounted for 20% of the variance in these scores. This study is based on depressed patients entering into an outpatient treatment protocol. All analyses were correlational in nature, and no causal links can be concluded. Our findings, identifying clinical correlates of hopelessness, provide clinicians with potential additional targets for assessment and treatment of suicidal risk. In particular, clinical attention to dysfunctional attitudes and problem solving skills may be important for further reduction of hopelessness and perhaps suicidal risk.
Bailey, Jennifer A.; Hill, Karl G.; Guttmannova, Katarina; Oesterle, Sabrina; Hawkins, J. David; Catalano, Richard F.; McMahon, Robert J.
2012-01-01
This study tested the association between parent illicit drug use disorder (DUD) in early adulthood and observed parenting practices at ages 27 – 28 and examined the following three, theoretically-derived models explaining this link: a) a disrupted parent adult functioning model, b) a pre-existing parent personality factor model, c) a disrupted adolescent family process model. Associations between study variables and child externalizing problems also were examined. Longitudinal data linking two generations were drawn from the Seattle Social Development Project (SSDP) and The SSDP Intergenerational Project (TIP), and included 167 parents and their 2- to 8-year-old child. Path modeling revealed that parent DUD in early adulthood predicted later observed low-skilled parenting, which was related to child externalizing problems. The pre-existing parent personality factor model was supported. Parent negative emotionality accounted for the association between parent early adult DUD and later parenting practices. Parent negative emotionality also was related directly to child externalizing behavior. Limited support for the disrupted transition to adulthood model was found. The disrupted adolescent family process model was not supported. Results suggest that problem drug use that occurs early in adulthood may affect later parenting skills, independent of subsequent parent drug use. Findings highlight the importance of parent negative emotionality in influencing their own problem behavior, their interactions with their child, and their child’s problem behavior. Prevention and treatment programs targeting young adult substance use, poor parenting practices, and child behavior problems should address parent personality factors that may contribute to these behaviors. PMID:22799581
Bailey, Jennifer A; Hill, Karl G; Guttmannova, Katarina; Oesterle, Sabrina; Hawkins, J David; Catalano, Richard F; McMahon, Robert J
2013-05-01
This study tested the association between parent illicit drug use disorder (DUD) in early adulthood and observed parenting practices at ages 27-28 and examined the following 3 theoretically derived models explaining this link: (a) a disrupted parent adult functioning model,(b) a preexisting parent personality factor model, and (c) a disrupted adolescent family process model. Associations between study variables and child externalizing problems also were examined. Longitudinal data linking 2 generations were drawn from the Seattle Social Development Project (SSDP) and The SSDP Intergenerational Project (TIP), and included 167 parents and their 2- to 8-year-old child. Path modeling revealed that parent DUD in early adulthood predicted later observed low-skilled parenting, which was related to child externalizing problems. The preexisting parent personality factor model was supported. Parent negative emotionality accounted for the association between parent early adult DUD and later parenting practices. Parent negative emotionality also was related directly to child externalizing behavior. Limited support for the disrupted transition to adulthood model was found. The disrupted adolescent family process model was not supported. Results suggest that problem drug use that occurs early in adulthood may affect later parenting skills, independent of subsequent parent drug use. Findings highlight the importance of parent negative emotionality in influencing his or her own problem behavior, interactions with his or her child, and his or her child's problem behavior. Prevention and treatment programs targeting young adult substance use, poor parenting practices, and child behavior problems should address parent personality factors that may contribute to these behaviors.
Temporal effects in trend prediction: identifying the most popular nodes in the future.
Zhou, Yanbo; Zeng, An; Wang, Wei-Hong
2015-01-01
Prediction is an important problem in different science domains. In this paper, we focus on trend prediction in complex networks, i.e. to identify the most popular nodes in the future. Due to the preferential attachment mechanism in real systems, nodes' recent degree and cumulative degree have been successfully applied to design trend prediction methods. Here we took into account more detailed information about the network evolution and proposed a temporal-based predictor (TBP). The TBP predicts the future trend by the node strength in the weighted network with the link weight equal to its exponential aging. Three data sets with time information are used to test the performance of the new method. We find that TBP have high general accuracy in predicting the future most popular nodes. More importantly, it can identify many potential objects with low popularity in the past but high popularity in the future. The effect of the decay speed in the exponential aging on the results is discussed in detail.
Temporal Effects in Trend Prediction: Identifying the Most Popular Nodes in the Future
Zhou, Yanbo; Zeng, An; Wang, Wei-Hong
2015-01-01
Prediction is an important problem in different science domains. In this paper, we focus on trend prediction in complex networks, i.e. to identify the most popular nodes in the future. Due to the preferential attachment mechanism in real systems, nodes’ recent degree and cumulative degree have been successfully applied to design trend prediction methods. Here we took into account more detailed information about the network evolution and proposed a temporal-based predictor (TBP). The TBP predicts the future trend by the node strength in the weighted network with the link weight equal to its exponential aging. Three data sets with time information are used to test the performance of the new method. We find that TBP have high general accuracy in predicting the future most popular nodes. More importantly, it can identify many potential objects with low popularity in the past but high popularity in the future. The effect of the decay speed in the exponential aging on the results is discussed in detail. PMID:25806810
Westgate, Erin C; Neighbors, Clayton; Heppner, Hannes; Jahn, Susanna; Lindgren, Kristen P
2014-01-01
Objective: This study investigated whether self-reports of alcohol-related postings on Facebook by oneself or one’s Facebook friends were related to common motives for drinking and were uniquely predictive of self-reported alcohol outcomes (alcohol consumption, problems, and cravings). Method: Pacific Northwest undergraduates completed a survey of alcohol outcomes, drinking motives, and alcoholrelated Facebook postings. Participants completed the survey online as part of a larger study on alcohol use and cognitive associations. Participants were randomly selected through the university registrar’s office and consisted of 1,106 undergraduates (449 men, 654 women, 2 transgender, 1 declined to answer) between the ages of 18 and 25 years (M = 20.40, SD = 1.60) at a large university in the Pacific Northwest. Seven participants were excluded from analyses because of missing or suspect data. Results: Alcohol-related postings on Facebook were significantly correlated with social, enhancement, conformity, and coping motives for drinking (all ps < .001). After drinking motives were controlled for, self–alcohol-related postings independently and positively predicted the number of drinks per week, alcohol-related problems, risk of alcohol use disorders, and alcohol cravings (all ps < .001). In contrast, friends’ alcohol-related postings only predicted the risk of alcohol use disorders (p < .05) and marginally predicted alcohol-related problems (p = .07). Conclusions: Posting alcohol-related content on social media platforms such as Facebook is associated with common motivations for drinking and is, in itself, a strong predictive indicator of drinking outcomes independent of drinking motives. Moreover, self-related posting activity appears to be more predictive than Facebook friends’ activity. These findings suggest that social media platforms may be a useful target for future preventative and intervention efforts. PMID:24766750
Fragkaki, Iro; Cima, Maaike; Meesters, Cor
2016-09-01
Morality deficits have been linked to callous-unemotional traits and externalizing problems in response to moral dilemmas, but these associations are still obscure in response to antisocial acts in adolescence. Limited evidence on young boys suggested that callous-unemotional traits and externalizing problems were associated with affective but not cognitive morality judgments. The present study investigated these associations in a community sample of 277 adolescents (M age = 15.35, 64 % females). Adolescents with high callous-unemotional traits showed deficits in affective but not cognitive morality, indicating that they can identify the appropriate moral emotions in others, but experience deviant moral emotions when imagining themselves committing antisocial acts. Externalizing problems and male gender were also strongly related to deficits in affective morality, but they had smaller associations with deficits in cognitive morality too. Implications for treatment and the justice system are discussed.
LeMoine, Kaitlyn A; Romirowsky, Abigail M; Woods, Kelsey E; Chronis-Tuscano, Andrea
2015-09-23
Parental psychopathology and parenting quality robustly predict negative outcomes among children with ADHD. Little research has investigated associations between paternal ADHD symptoms and parenting, though there is clear evidence linking maternal ADHD symptoms with both suboptimal parenting and child conduct problems, and considerable research supporting fathers' significant contributions to their children's development. This cross-sectional study examined psychopathology and parenting in a sample of fathers (N = 102) and their 5- to 12-year-old children with previously diagnosed ADHD. Results suggested that paternal antisocial personality disorder (ASPD) symptoms (rather than ADHD symptoms) were robustly associated with child conduct problems, with an indirect effect through paternal negative parenting. This study suggests that negative parenting may be a potential mechanism by which paternal ASPD is associated with child conduct problems, and demonstrates the importance of considering co-occurring psychopathology in research examining adult ADHD, parenting, and child outcomes. © The Author(s) 2015.
Hossner, Ernst-Joachim
2009-01-01
The problem of a bidirectional link between thought and action is approached from the perspective of cognitive movement science. The metaphor of the "Badische Zimmer" - an adaptation of Searle's Chinese room metaphor - is used to illustrate shortcomings in the classical conception of linear information processing and to introduce some features which current theories of movement control and learning should embrace. On this basis, the case is made for a return to an ideomotor view of motor control and learning based on effect prediction (E') as a function of the situational context (S') and one's own motor responses (R'). The relevance of the derived concept of sensorimotor chains linking elementary S'R'E' units in the course of motor learning is finally discussed with respect to potential implications for an integrative theory of perception, action, and decision making.
Job stress, unwinding and drinking in transit operators.
Delaney, William P; Grube, Joel W; Greiner, Birgit; Fisher, June M; Ragland, David R
2002-07-01
This study tests the spillover model of the effects of work stress on after-work drinking, using the variable "length of time to unwind" as a mediator. A total of 1,974 transit operators were contacted and 1,553 (79%) of them participated in a personal interview. Complete data on the variables in this analysis were available for 1,208 respondents (84% men). Using latent variable structural equation modeling, a model was tested that predicted that daily job problems, skipped meals and less social support from supervisor would increase alcohol consumption through the mediator, length of time to unwind and relax after work. Increased alcohol consumption was, in turn, hypothesized to increase drinking problems. As predicted, skipped meals and daily job problems increased length of time to unwind and had an indirect positive relationship with overall drinking, even when controlling for drinking norms and demographic variables. Overall drinking was positively associated with drinking problems. Supervisor support at work, however, did not significantly influence length of time to unwind. Difficulty unwinding (longer time to unwind) did not have direct effects on drinking problems; however, indirect effects through overall drinking were observed. These results provide preliminary support for the mediating role of length of time to unwind and relax after work in a spillover model of the stress-drinking relationship. This research introduces a new mediator and empirical links between job problems, length of time to unwind, drinking and drinking problems, which ground more substantively the domains of work stress and alcohol consumption.
Prediction of missing links and reconstruction of complex networks
NASA Astrophysics Data System (ADS)
Zhang, Cheng-Jun; Zeng, An
2016-04-01
Predicting missing links in complex networks is of great significance from both theoretical and practical point of view, which not only helps us understand the evolution of real systems but also relates to many applications in social, biological and online systems. In this paper, we study the features of different simple link prediction methods, revealing that they may lead to the distortion of networks’ structural and dynamical properties. Moreover, we find that high prediction accuracy is not definitely corresponding to a high performance in preserving the network properties when using link prediction methods to reconstruct networks. Our work highlights the importance of considering the feedback effect of the link prediction methods on network properties when designing the algorithms.
Vitaro, Frank; Brendgen, Mara; Girard, Alain; Dionne, Ginette; Boivin, Michel
2018-01-11
Gambling participation and low academic performance are related during adolescence, but the causal mechanisms underlying this link are unclear. It is possible that gambling participation impairs academic performance. Alternatively, the link between gambling participation and low academic performance could be explained by common underlying risk factors such as impulsivity and socio-family adversity. It could also be explained by other current correlated problem behaviors such as substance use. The goal of the present study was to examine whether concurrent and longitudinal links between gambling participation and low academic performance exist from age 14 to age 17 years, net of common antecedent factors and current substance use. A convenience sample of 766 adolescents (50.6% males) from a longitudinal twin sample participated in the study. Analyses revealed significant, albeit modest, concurrent links at both ages between gambling participation and academic performance. There was also a longitudinal link between gambling participation at age 14 and academic performance at age 17, which persisted after controlling for age 12 impulsivity and socio-family adversity as well as current substance use. Gambling participation predicts a decrease in academic performance during adolescence, net of concurrent and antecedent personal and familial risk factors.
Meta-path based heterogeneous combat network link prediction
NASA Astrophysics Data System (ADS)
Li, Jichao; Ge, Bingfeng; Yang, Kewei; Chen, Yingwu; Tan, Yuejin
2017-09-01
The combat system-of-systems in high-tech informative warfare, composed of many interconnected combat systems of different types, can be regarded as a type of complex heterogeneous network. Link prediction for heterogeneous combat networks (HCNs) is of significant military value, as it facilitates reconfiguring combat networks to represent the complex real-world network topology as appropriate with observed information. This paper proposes a novel integrated methodology framework called HCNMP (HCN link prediction based on meta-path) to predict multiple types of links simultaneously for an HCN. More specifically, the concept of HCN meta-paths is introduced, through which the HCNMP can accumulate information by extracting different features of HCN links for all the six defined types. Next, an HCN link prediction model, based on meta-path features, is built to predict all types of links of the HCN simultaneously. Then, the solution algorithm for the HCN link prediction model is proposed, in which the prediction results are obtained by iteratively updating with the newly predicted results until the results in the HCN converge or reach a certain maximum iteration number. Finally, numerical experiments on the dataset of a real HCN are conducted to demonstrate the feasibility and effectiveness of the proposed HCNMP, in comparison with 30 baseline methods. The results show that the performance of the HCNMP is superior to those of the baseline methods.
Migraines and Gastrointestinal Problems: Is There a Link?
... there a link? Is there any link between migraines and gastrointestinal problems? Answers from Jerry W. Swanson, ... link. Nausea and vomiting are often associated with migraine attacks. In young children, several syndromes that cause ...
Seebacher, Frank; Franklin, Craig E
2012-06-19
The emerging field of Conservation Physiology links environmental change and ecological success by the application of physiological theory, approaches and tools to elucidate and address conservation problems. Human activity has changed the natural environment to a point where the viability of many ecosystems is now under threat. There are already many descriptions of how changes in biological patterns are correlated with environmental changes. The next important step is to determine the causative relationship between environmental variability and biological systems. Physiology provides the mechanistic link between environmental change and ecological patterns. Physiological research, therefore, should be integrated into conservation to predict the biological consequences of human activity, and to identify those species or populations that are most vulnerable.
Linking Family Characteristics with Poor Peer Relations: The Mediating Role of Conduct Problems
Bierman, Karen Linn; Smoot, David L.
2012-01-01
Parent, teacher, and peer ratings were collected for 75 grade school boys to test the hypothesis that certain family interaction patterns would be associated with poor peer relations. Path analyses provided support for a mediational model, in which punitive and ineffective discipline was related to child conduct problems in home and school settings which, in turn, predicted poor peer relations. Further analyses suggested that distinct subgroups of boys could be identified who exhibited conduct problems at home only, at school only, in both settings, or in neither setting. Boys who exhibited cross-situational conduct problems were more likely to experience multiple concurrent problems (e.g., in both home and school settings) and were more likely than any other group to experience poor peer relations. However, only about one-third of the boys with poor peer relations in this sample exhibited problem profiles consistent with the proposed model (e.g., experienced high rates of punitive/ineffective home discipline and exhibited conduct problems in home and school settings), suggesting that the proposed model reflects one common (but not exclusive) pathway to poor peer relations. PMID:1865049
Hastings, Paul D; Helm, Jonathan; Mills, Rosemary S L; Serbin, Lisa A; Stack, Dale M; Schwartzman, Alex E
2015-07-01
This investigation evaluated a multilevel model of dispositional and environmental factors contributing to the development of internalizing problems from preschool-age to school-age. In a sample of 375 families (185 daughters, 190 sons) drawn from three independent samples, preschoolers' behavioral inhibition, cortisol and gender were examined as moderators of the links between mothers' negative parenting behavior, negative emotional characteristics, and socioeconomic status when children were 3.95 years, and their internalizing problems when they were 8.34 years. Children's dispositional characteristics moderated all associations between these environmental factors and mother-reported internalizing problems in patterns that were consistent with either diathesis-stress or differential-susceptibility models of individual-environment interaction, and with gender models of developmental psychopathology. Greater inhibition and lower socioeconomic status were directly predictive of more teacher reported internalizing problems. These findings highlight the importance of using multilevel models within a bioecological framework to understand the complex pathways through which internalizing difficulties develop.
Harvey, Elizabeth A; Friedman-Weieneth, Julie L; Goldstein, Lauren H; Sherman, Alison H
2007-02-01
This study examined 3-year-old children who were classified as hyperactive (HYP), oppositional-defiant (OD), hyperactive and oppositional defiant (HYP/OD), and non-problem based on mothers' reports of behavior. Using fathers,' teachers,' and observers' ratings of children's behavior, concurrent validity was excellent for the HYP/OD group, moderate for the HYP group, and poor for the OD group. As predicted, both the HYP/OD and HYP groups reported more prenatal/perinatal birth complications and a greater family history of hyperactivity than did non-problem children. Furthermore, the HYP/OD group showed a greater family history of conduct disorder and oppositional defiant disorder (ODD) symptoms than did non-problem children; however, the HYP group also showed a greater family history of ODD than did non-problem children. Results suggest that as early as age 3, these behavior subtypes appear to be linked to biologically-based risk-factors in ways that are consistent with theories of the development of ADHD.
A new evolutionary system for evolving artificial neural networks.
Yao, X; Liu, Y
1997-01-01
This paper presents a new evolutionary system, i.e., EPNet, for evolving artificial neural networks (ANNs). The evolutionary algorithm used in EPNet is based on Fogel's evolutionary programming (EP). Unlike most previous studies on evolving ANN's, this paper puts its emphasis on evolving ANN's behaviors. Five mutation operators proposed in EPNet reflect such an emphasis on evolving behaviors. Close behavioral links between parents and their offspring are maintained by various mutations, such as partial training and node splitting. EPNet evolves ANN's architectures and connection weights (including biases) simultaneously in order to reduce the noise in fitness evaluation. The parsimony of evolved ANN's is encouraged by preferring node/connection deletion to addition. EPNet has been tested on a number of benchmark problems in machine learning and ANNs, such as the parity problem, the medical diagnosis problems, the Australian credit card assessment problem, and the Mackey-Glass time series prediction problem. The experimental results show that EPNet can produce very compact ANNs with good generalization ability in comparison with other algorithms.
NASA Astrophysics Data System (ADS)
Søe-Knudsen, Alf; Sorokin, Sergey
2011-06-01
This rapid communication is concerned with justification of the 'rule of thumb', which is well known to the community of users of the finite element (FE) method in dynamics, for the accuracy assessment of the wave finite element (WFE) method. An explicit formula linking the size of a window in the dispersion diagram, where the WFE method is trustworthy, with the coarseness of a FE mesh employed is derived. It is obtained by the comparison of the exact Pochhammer-Chree solution for an elastic rod having the circular cross-section with its WFE approximations. It is shown that the WFE power flow predictions are also valid within this window.
Information filtering based on transferring similarity.
Sun, Duo; Zhou, Tao; Liu, Jian-Guo; Liu, Run-Ran; Jia, Chun-Xiao; Wang, Bing-Hong
2009-07-01
In this Brief Report, we propose an index of user similarity, namely, the transferring similarity, which involves all high-order similarities between users. Accordingly, we design a modified collaborative filtering algorithm, which provides remarkably higher accurate predictions than the standard collaborative filtering. More interestingly, we find that the algorithmic performance will approach its optimal value when the parameter, contained in the definition of transferring similarity, gets close to its critical value, before which the series expansion of transferring similarity is convergent and after which it is divergent. Our study is complementary to the one reported in [E. A. Leicht, P. Holme, and M. E. J. Newman, Phys. Rev. E 73, 026120 (2006)], and is relevant to the missing link prediction problem.
Liang, Tengfei; Li, Qi; Ye, Wenjing
2013-07-01
A systematic study on the performance of two empirical gas-wall interaction models, the Maxwell model and the Cercignani-Lampis (CL) model, in the entire Knudsen range is conducted. The models are evaluated by examining the accuracy of key macroscopic quantities such as temperature, density, and pressure, in three benchmark thermal problems, namely the Fourier thermal problem, the Knudsen force problem, and the thermal transpiration problem. The reference solutions are obtained from a validated hybrid DSMC-MD algorithm developed in-house. It has been found that while both models predict temperature and density reasonably well in the Fourier thermal problem, the pressure profile obtained from Maxwell model exhibits a trend that opposes that from the reference solution. As a consequence, the Maxwell model is unable to predict the orientation change of the Knudsen force acting on a cold cylinder embedded in a hot cylindrical enclosure at a certain Knudsen number. In the simulation of the thermal transpiration coefficient, although all three models overestimate the coefficient, the coefficient obtained from CL model is the closest to the reference solution. The Maxwell model performs the worst. The cause of the overestimated coefficient is investigated and its link to the overly constrained correlation between the tangential momentum accommodation coefficient and the tangential energy accommodation coefficient inherent in the models is pointed out. Directions for further improvement of models are suggested.
Patrick, Christopher J; Venables, Noah C; Yancey, James R; Hicks, Brian M; Nelson, Lindsay D; Kramer, Mark D
2013-08-01
A crucial challenge in efforts to link psychological disorders to neural systems, with the aim of developing biologically informed conceptions of such disorders, is the problem of method variance (Campbell & Fiske, 1959). Since even measures of the same construct in differing domains correlate only moderately, it is unsurprising that large sample studies of diagnostic biomarkers yield only modest associations. To address this challenge, a construct-network approach is proposed in which psychometric operationalizations of key neurobehavioral constructs serve as anchors for identifying neural indicators of psychopathology-relevant dispositions, and as vehicles for bridging between domains of clinical problems and neurophysiology. An empirical illustration is provided for the construct of inhibition-disinhibition, which is of central relevance to problems entailing deficient impulse control. Findings demonstrate that: (1) a well-designed psychometric index of trait disinhibition effectively predicts externalizing problems of multiple types, (2) this psychometric measure of disinhibition shows reliable brain response correlates, and (3) psychometric and brain-response indicators can be combined to form a joint psychoneurometric factor that predicts effectively across clinical and physiological domains. As a methodology for bridging between clinical problems and neural systems, the construct-network approach provides a concrete means by which existing conceptions of psychological disorders can accommodate and be reshaped by neurobiological insights. PsycINFO Database Record (c) 2013 APA, all rights reserved.
Linking empathy to visuospatial perspective-taking in gambling addiction.
Tomei, Alexander; Besson, Jacques; Grivel, Jeremy
2017-04-01
It has been demonstrated that people suffering from substance-related addictions are less empathic than their non-addicted counterparts. Our first aim was to verify if this is also true for behavioral addictions. We hypothesized that problem gamblers are less empathic than healthy controls. Our second aim was to identify a cognitive marker of empathy that could be targeted in cognitive rehabilitation strategies. We propose that a potential cognitive marker of empathy could be visuospatial perspective-taking. Specifically, we hypothesized that visuospatial perspective-taking performances are lower in problem gamblers compared to healthy controls and that these visuospatial performances predict empathy. Thirty-one non-gamblers, 24 healthy gamblers, and 21 problem gamblers performed a visuospatial perspective-taking task before completing the Interpersonal Reactivity Index (IRI; Davis, 1980; Davis, 1983). Problem gamblers had decreased empathy and lower performance at the visuospatial perspective-taking task than non-gamblers and healthy gamblers. Furthermore, we confirmed that visuospatial perspective-taking abilities predict empathy on the IRI dimensions of interpersonal perspective-taking and personal distress. The present study provides new evidence that reduced empathy is not limited to subjects with substance-related addictions; rather, it extends to behavioral addictions. Visuospatial perspective-taking may be a viable cognitive marker for use as a rehabilitation target of empathy. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.
Frndak, Seth E; Kordovski, Victoria M; Cookfair, Diane; Rodgers, Jonathan D; Weinstock-Guttman, Bianca; Benedict, Ralph H B
2015-02-01
Unemployment is common in multiple sclerosis (MS) and detrimental to quality of life. Studies suggest disclosure of diagnosis is an adaptive strategy for patients. However, the role of cognitive deficits and psychiatric symptoms in disclosure are not well studied. The goals of this paper were to (a) determine clinical factors most predictive of disclosure, and (b) measure the effects of disclosure on workplace problems and accommodations in employed patients. We studied two overlapping cohorts: a cross-sectional sample (n = 143) to determine outcomes associated with disclosure, and a longitudinal sample (n = 103) compared at four time points over one year on reported problems and accommodations. A case study of six patients, disclosing during monitoring, was also included. Disclosure was associated with greater physical disability but not cognitive impairment. Logistic regression predicting disclosure status retained physical disability, accommodations and years of employment (p < 0.0001). Disclosed patients reported more work problems and accommodations over time. The case study revealed that reasons for disclosing are multifaceted, including connection to employer, decreased mobility and problems at work. Although cognitive impairment is linked to unemployment, it does not appear to inform disclosure decisions. Early disclosure may help maintain employment if followed by appropriate accommodations. © The Author(s), 2014.
Trust from the past: Bayesian Personalized Ranking based Link Prediction in Knowledge Graphs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Baichuan; Choudhury, Sutanay; Al-Hasan, Mohammad
2016-02-01
Estimating the confidence for a link is a critical task for Knowledge Graph construction. Link prediction, or predicting the likelihood of a link in a knowledge graph based on prior state is a key research direction within this area. We propose a Latent Feature Embedding based link recommendation model for prediction task and utilize Bayesian Personalized Ranking based optimization technique for learning models for each predicate. Experimental results on large-scale knowledge bases such as YAGO2 show that our approach achieves substantially higher performance than several state-of-art approaches. Furthermore, we also study the performance of the link prediction algorithm in termsmore » of topological properties of the Knowledge Graph and present a linear regression model to reason about its expected level of accuracy.« less
Abu-Raiya, Hisham; Pargament, Kenneth I; Krause, Neal
2016-05-01
Previous studies have established robust links between religious/spiritual struggles (r/s struggles) and poorer well-being and psychological distress. A critical issue involves identifying the religious factors that buffer this relationship. This is the first study to empirically address this question. Specifically, it examines four religious factors (i.e., religious commitment, life sanctification, religious support, religious hope) as potential buffers of the links between r/s struggle and one indicator of subjective well-being (i.e., happiness) and one indicator of psychological distress (i.e., depressive symptoms). We utilized a cross-sectional design and a nationally representative sample of American adults (N = 2140) dealing with a wide range of major life stressors. We found that the interactions between r/s struggle and all potential moderators were significant in predicting happiness and/or depression. The linkage between r/s struggle and lower levels of happiness was moderated by higher levels of each of the four proposed religious buffers. Religious commitment and life sanctification moderated the ties between r/s struggles and depressive symptoms. The findings underscore the multifaceted character of religion: Paradoxically, religion may be a source of solutions to problems that may be an inherent part of religious life.
Azar, Sandra T.; Stevenson, Michael T.; Johnson, David R.
2014-01-01
Parents with intellectual disabilities (PID) are over-represented in the child protective services (CPS) system. This study examined a more nuanced view of the role of cognition in parenting risk. Its goal was to validate a social information processing (SIP) model of child neglect that draws on social cognition research and advances in neuroscience. Mothers who had CPS child neglect cases were compared with mothers with no CPS involvement on a set of SIP factors. Mothers with low IQs were oversampled. As predicted, the Neglect group had significantly greater SIP problems than the Comparison mothers. SIP problems were associated with direct measures of neglect (e.g., cognitive stimulation provided children, home hygiene, belief regarding causes of child injuries). Further, for the direct measures that were most closely linked to CPS Neglect Status, IQ did not add significant predictive capacity beyond SIP factors in preliminary model testing. Implications for intervention with PID discussed. PMID:25506405
Prolonged Financial Distress After the Deepwater Horizon Oil Spill Predicts Behavioral Health.
Buckingham-Howes, Stacy; Holmes, Katherine; Glenn Morris, J; Grattan, Lynn M
2018-03-13
The economic impact of disasters is well known; however, the link between financial loss and behavioral health problems is unknown. Participants included 198 adults of ages 21 to 82, living within 10 miles of the Gulf Coast during the Deepwater Horizon Oil Spill and were involved in the fishing, harvesting, seafood processing, or service/tourism industries. The functional impact of financial resource loss at 2.5 years post spill was measured using the 26-item Financial Life Events Checklist (FLEC). Individuals responded to financial distress by reducing social events and utility bills and changing food-shopping habits. The FLEC significantly predicted higher drug use (Drug Abuse Screening Test), alcohol use (Alcohol Use Disorders Identification Test), mood problems (Profile of Mood States), and depressive symptoms (Beck Depression Inventory II) (p values ≤ 0.05) 4.5 years after the spill. This preliminary study supports the notion that the functional impact of financial loss has a long-term impact on behavioral health after an oil spill.
Link prediction based on local community properties
NASA Astrophysics Data System (ADS)
Yang, Xu-Hua; Zhang, Hai-Feng; Ling, Fei; Cheng, Zhi; Weng, Guo-Qing; Huang, Yu-Jiao
2016-09-01
The link prediction algorithm is one of the key technologies to reveal the inherent rule of network evolution. This paper proposes a novel link prediction algorithm based on the properties of the local community, which is composed of the common neighbor nodes of any two nodes in the network and the links between these nodes. By referring to the node degree and the condition of assortativity or disassortativity in a network, we comprehensively consider the effect of the shortest path and edge clustering coefficient within the local community on node similarity. We numerically show the proposed method provide good link prediction results.
MIDER: Network Inference with Mutual Information Distance and Entropy Reduction
Villaverde, Alejandro F.; Ross, John; Morán, Federico; Banga, Julio R.
2014-01-01
The prediction of links among variables from a given dataset is a task referred to as network inference or reverse engineering. It is an open problem in bioinformatics and systems biology, as well as in other areas of science. Information theory, which uses concepts such as mutual information, provides a rigorous framework for addressing it. While a number of information-theoretic methods are already available, most of them focus on a particular type of problem, introducing assumptions that limit their generality. Furthermore, many of these methods lack a publicly available implementation. Here we present MIDER, a method for inferring network structures with information theoretic concepts. It consists of two steps: first, it provides a representation of the network in which the distance among nodes indicates their statistical closeness. Second, it refines the prediction of the existing links to distinguish between direct and indirect interactions and to assign directionality. The method accepts as input time-series data related to some quantitative features of the network nodes (such as e.g. concentrations, if the nodes are chemical species). It takes into account time delays between variables, and allows choosing among several definitions and normalizations of mutual information. It is general purpose: it may be applied to any type of network, cellular or otherwise. A Matlab implementation including source code and data is freely available (http://www.iim.csic.es/~gingproc/mider.html). The performance of MIDER has been evaluated on seven different benchmark problems that cover the main types of cellular networks, including metabolic, gene regulatory, and signaling. Comparisons with state of the art information–theoretic methods have demonstrated the competitive performance of MIDER, as well as its versatility. Its use does not demand any a priori knowledge from the user; the default settings and the adaptive nature of the method provide good results for a wide range of problems without requiring tuning. PMID:24806471
MIDER: network inference with mutual information distance and entropy reduction.
Villaverde, Alejandro F; Ross, John; Morán, Federico; Banga, Julio R
2014-01-01
The prediction of links among variables from a given dataset is a task referred to as network inference or reverse engineering. It is an open problem in bioinformatics and systems biology, as well as in other areas of science. Information theory, which uses concepts such as mutual information, provides a rigorous framework for addressing it. While a number of information-theoretic methods are already available, most of them focus on a particular type of problem, introducing assumptions that limit their generality. Furthermore, many of these methods lack a publicly available implementation. Here we present MIDER, a method for inferring network structures with information theoretic concepts. It consists of two steps: first, it provides a representation of the network in which the distance among nodes indicates their statistical closeness. Second, it refines the prediction of the existing links to distinguish between direct and indirect interactions and to assign directionality. The method accepts as input time-series data related to some quantitative features of the network nodes (such as e.g. concentrations, if the nodes are chemical species). It takes into account time delays between variables, and allows choosing among several definitions and normalizations of mutual information. It is general purpose: it may be applied to any type of network, cellular or otherwise. A Matlab implementation including source code and data is freely available (http://www.iim.csic.es/~gingproc/mider.html). The performance of MIDER has been evaluated on seven different benchmark problems that cover the main types of cellular networks, including metabolic, gene regulatory, and signaling. Comparisons with state of the art information-theoretic methods have demonstrated the competitive performance of MIDER, as well as its versatility. Its use does not demand any a priori knowledge from the user; the default settings and the adaptive nature of the method provide good results for a wide range of problems without requiring tuning.
CD-Based Indices for Link Prediction in Complex Network.
Wang, Tao; Wang, Hongjue; Wang, Xiaoxia
2016-01-01
Lots of similarity-based algorithms have been designed to deal with the problem of link prediction in the past decade. In order to improve prediction accuracy, a novel cosine similarity index CD based on distance between nodes and cosine value between vectors is proposed in this paper. Firstly, node coordinate matrix can be obtained by node distances which are different from distance matrix and row vectors of the matrix are regarded as coordinates of nodes. Then, cosine value between node coordinates is used as their similarity index. A local community density index LD is also proposed. Then, a series of CD-based indices include CD-LD-k, CD*LD-k, CD-k and CDI are presented and applied in ten real networks. Experimental results demonstrate the effectiveness of CD-based indices. The effects of network clustering coefficient and assortative coefficient on prediction accuracy of indices are analyzed. CD-LD-k and CD*LD-k can improve prediction accuracy without considering the assortative coefficient of network is negative or positive. According to analysis of relative precision of each method on each network, CD-LD-k and CD*LD-k indices have excellent average performance and robustness. CD and CD-k indices perform better on positive assortative networks than on negative assortative networks. For negative assortative networks, we improve and refine CD index, referred as CDI index, combining the advantages of CD index and evolutionary mechanism of the network model BA. Experimental results reveal that CDI index can increase prediction accuracy of CD on negative assortative networks.
CD-Based Indices for Link Prediction in Complex Network
Wang, Tao; Wang, Hongjue; Wang, Xiaoxia
2016-01-01
Lots of similarity-based algorithms have been designed to deal with the problem of link prediction in the past decade. In order to improve prediction accuracy, a novel cosine similarity index CD based on distance between nodes and cosine value between vectors is proposed in this paper. Firstly, node coordinate matrix can be obtained by node distances which are different from distance matrix and row vectors of the matrix are regarded as coordinates of nodes. Then, cosine value between node coordinates is used as their similarity index. A local community density index LD is also proposed. Then, a series of CD-based indices include CD-LD-k, CD*LD-k, CD-k and CDI are presented and applied in ten real networks. Experimental results demonstrate the effectiveness of CD-based indices. The effects of network clustering coefficient and assortative coefficient on prediction accuracy of indices are analyzed. CD-LD-k and CD*LD-k can improve prediction accuracy without considering the assortative coefficient of network is negative or positive. According to analysis of relative precision of each method on each network, CD-LD-k and CD*LD-k indices have excellent average performance and robustness. CD and CD-k indices perform better on positive assortative networks than on negative assortative networks. For negative assortative networks, we improve and refine CD index, referred as CDI index, combining the advantages of CD index and evolutionary mechanism of the network model BA. Experimental results reveal that CDI index can increase prediction accuracy of CD on negative assortative networks. PMID:26752405
Toward link predictability of complex networks
Lü, Linyuan; Pan, Liming; Zhou, Tao; Zhang, Yi-Cheng; Stanley, H. Eugene
2015-01-01
The organization of real networks usually embodies both regularities and irregularities, and, in principle, the former can be modeled. The extent to which the formation of a network can be explained coincides with our ability to predict missing links. To understand network organization, we should be able to estimate link predictability. We assume that the regularity of a network is reflected in the consistency of structural features before and after a random removal of a small set of links. Based on the perturbation of the adjacency matrix, we propose a universal structural consistency index that is free of prior knowledge of network organization. Extensive experiments on disparate real-world networks demonstrate that (i) structural consistency is a good estimation of link predictability and (ii) a derivative algorithm outperforms state-of-the-art link prediction methods in both accuracy and robustness. This analysis has further applications in evaluating link prediction algorithms and monitoring sudden changes in evolving network mechanisms. It will provide unique fundamental insights into the above-mentioned academic research fields, and will foster the development of advanced information filtering technologies of interest to information technology practitioners. PMID:25659742
Prediction in complex systems: The case of the international trade network
NASA Astrophysics Data System (ADS)
Vidmer, Alexandre; Zeng, An; Medo, Matúš; Zhang, Yi-Cheng
2015-10-01
Predicting the future evolution of complex systems is one of the main challenges in complexity science. Based on a current snapshot of a network, link prediction algorithms aim to predict its future evolution. We apply here link prediction algorithms to data on the international trade between countries. This data can be represented as a complex network where links connect countries with the products that they export. Link prediction techniques based on heat and mass diffusion processes are employed to obtain predictions for products exported in the future. These baseline predictions are improved using a recent metric of country fitness and product similarity. The overall best results are achieved with a newly developed metric of product similarity which takes advantage of causality in the network evolution.
Predicting HIV/STD risk level and substance use disorders among incarcerated adolescents.
Rowe, Cynthia L; Wang, Wei; Greenbaum, Paul; Liddle, Howard A
2008-12-01
Incarcerated adolescents are among the most vulnerable groups for STD infection, and substance abuse is prevalent in over half of this population. Substance abuse and HIV/STD-associated risk behaviors are closely linked among juvenile justice-involved youth, but it is unclear whether common antecedents explain these different problems. The current study examined predictors of HIV/STD risk level and substance use disorders, and investigated whether family variables added unique predictive variance for these problems among incarcerated youth. The sample included 154 substance-involved youth ages 13 to 17 recruited in detention facilities in Miami and Tampa, FL and was primarily male (82%) and African-American (58%). Using a comprehensive assessment strategy with data obtained from youth report, parent report, and laboratory confirmed STD testing, the results show that delinquency is a consistent predictor of both HIV/STD risk level and substance use disorders, and also that substance use directly predicts HIV/STD risk level among incarcerated adolescents. Consistent with previous research, family conflict is an important predictor of substance use disorders even after controlling for other factors. The results suggest the need for integrated family-based interventions addressing delinquency, substance abuse, and HIV/STD-associated risk factors with juvenile justice-involved adolescents.
Traveltime and dispersion in the Potomac River, Cumberland, Maryland, to Washington, D.C.
Taylor, K.R.; James, R.W.; Helinsky, B.M.
1984-01-01
Data from two traveltime and dispersion studies, using rhodamine dye, are used to develop a generalized procedure for predicting traveltime and downstream concentrations resulting from spillage of water-soluble substances at any point along the Potomac River from Cumberland, Maryland, to Washington, D.C. The procedure will allow the approximate solution to almost any spillage problem concerning traveltime and concentration during periods of relatively steady flow between 50- and 95-percent flow duration. A new procedure for calculating unit peak concentration is derived. The new procedure, based on the similarity in shape of a time-concentration curve and a scalene triangle, allows unit peak concentration to be expressed in terms of the length of the dye cloud. This approach facilitates the linking of peak-concentration attenuation curves for long reaches of rivers which are divided into subreaches for study. An example problem is solved for a hypothetical spill of 20,000 pounds of contaminant at Magnolia, West Virginia. The predicted traveltime of the leading edge, peak concentration, and trailing edge to Point of Rocks, Maryland (110 miles downstream), are 295 , 375, and 540 hours, respectively, for a flow duration of 80 percent. The predicted maximum concentration is 340 micrograms/L. (USGS)
Pattern-oriented modelling: a ‘multi-scope’ for predictive systems ecology
Grimm, Volker; Railsback, Steven F.
2012-01-01
Modern ecology recognizes that modelling systems across scales and at multiple levels—especially to link population and ecosystem dynamics to individual adaptive behaviour—is essential for making the science predictive. ‘Pattern-oriented modelling’ (POM) is a strategy for doing just this. POM is the multi-criteria design, selection and calibration of models of complex systems. POM starts with identifying a set of patterns observed at multiple scales and levels that characterize a system with respect to the particular problem being modelled; a model from which the patterns emerge should contain the right mechanisms to address the problem. These patterns are then used to (i) determine what scales, entities, variables and processes the model needs, (ii) test and select submodels to represent key low-level processes such as adaptive behaviour, and (iii) find useful parameter values during calibration. Patterns are already often used in these ways, but a mini-review of applications of POM confirms that making the selection and use of patterns more explicit and rigorous can facilitate the development of models with the right level of complexity to understand ecological systems and predict their response to novel conditions. PMID:22144392
Self-assembly of knots and links
NASA Astrophysics Data System (ADS)
Orlandini, Enzo; Polles, Guido; Marenduzzo, Davide; Micheletti, Cristian
2017-03-01
Guiding the self-assembly of identical building blocks towards complex three-dimensional structures with a set of desired properties is a major goal in material science, chemistry and physics. A particularly challenging problem, especially explored in synthetic chemistry, is that of self-assembling closed structures with a target topology starting by simple geometrical templates. Here we overview and revisit recent advancements, based on stochastic simulations, where the geometry of rigid helical templates with functionalised sticky ends has been designed for self-assembling efficiently and reproducibly into a wide range of three-dimensional closed structures. Notably, these include non trivial topologies of links and knots, including the 819 knot that we had predicted to be highly encodable and that has only recently been obtained experimentally. By appropriately tuning the parameters that define the template shape, we show that, for fixed concentration of templates, the assembly process can be directed towards the formation of specific knotted and linked structures such as the trefoils, pentafoil knots, Hopf and Solomon links. More exotic and unexpected knots and links are also found. Our results should be relevant to the design of new protocols that can both increase and broaden the population of synthetise molecular knots and catenanes.
Link prediction measures considering different neighbors’ effects and application in social networks
NASA Astrophysics Data System (ADS)
Luo, Peng; Wu, Chong; Li, Yongli
Link prediction measures have been attracted particular attention in the field of mathematical physics. In this paper, we consider the different effects of neighbors in link prediction and focus on four different situations: only consider the individual’s own effects; consider the effects of individual, neighbors and neighbors’ neighbors; consider the effects of individual, neighbors, neighbors’ neighbors, neighbors’ neighbors’ neighbors and neighbors’ neighbors’ neighbors’ neighbors; consider the whole network participants’ effects. Then, according to the four situations, we present our link prediction models which also take the effects of social characteristics into consideration. An artificial network is adopted to illustrate the parameter estimation based on logistic regression. Furthermore, we compare our methods with the some other link prediction methods (LPMs) to examine the validity of our proposed model in online social networks. The results show the superior of our proposed link prediction methods compared with others. In the application part, our models are applied to study the social network evolution and used to recommend friends and cooperators in social networks.
NASA Astrophysics Data System (ADS)
Vologodskii, Alexander
2016-09-01
The widespread circular form of DNA molecules inside cells creates very serious topological problems during replication. Due to the helical structure of the double helix the parental strands of circular DNA form a link of very high order, and yet they have to be unlinked before the cell division. DNA topoisomerases, the enzymes that catalyze passing of one DNA segment through another, solve this problem in principle. However, it is very difficult to remove all entanglements between the replicated DNA molecules due to huge length of DNA comparing to the cell size. One strategy that nature uses to overcome this problem is to create the topoisomerases that can dramatically reduce the fraction of linked circular DNA molecules relative to the corresponding fraction at thermodynamic equilibrium. This striking property of the enzymes means that the enzymes that interact with DNA only locally can access their topology, a global property of circular DNA molecules. This review considers the experimental studies of the phenomenon and analyzes the theoretical models that have been suggested in attempts to explain it. We describe here how various models of enzyme action can be investigated computationally. There is no doubt at the moment that we understand basic principles governing enzyme action. Still, there are essential quantitative discrepancies between the experimental data and the theoretical predictions. We consider how these discrepancies can be overcome.
NASA Astrophysics Data System (ADS)
de Montera, L.; Mallet, C.; Barthès, L.; Golé, P.
2008-08-01
This paper shows how nonlinear models originally developed in the finance field can be used to predict rain attenuation level and volatility in Earth-to-Satellite links operating at the Extremely High Frequencies band (EHF, 20 50 GHz). A common approach to solving this problem is to consider that the prediction error corresponds only to scintillations, whose variance is assumed to be constant. Nevertheless, this assumption does not seem to be realistic because of the heteroscedasticity of error time series: the variance of the prediction error is found to be time-varying and has to be modeled. Since rain attenuation time series behave similarly to certain stocks or foreign exchange rates, a switching ARIMA/GARCH model was implemented. The originality of this model is that not only the attenuation level, but also the error conditional distribution are predicted. It allows an accurate upper-bound of the future attenuation to be estimated in real time that minimizes the cost of Fade Mitigation Techniques (FMT) and therefore enables the communication system to reach a high percentage of availability. The performance of the switching ARIMA/GARCH model was estimated using a measurement database of the Olympus satellite 20/30 GHz beacons and this model is shown to outperform significantly other existing models. The model also includes frequency scaling from the downlink frequency to the uplink frequency. The attenuation effects (gases, clouds and rain) are first separated with a neural network and then scaled using specific scaling factors. As to the resulting uplink prediction error, the error contribution of the frequency scaling step is shown to be larger than that of the downlink prediction, indicating that further study should focus on improving the accuracy of the scaling factor.
Criminogenic Needs, Substance Use, and Offending among Rural Stimulant Users
Timko, Christine; Booth, Brenda M.; Han, Xiaotong; Schultz, Nicole R.; Blonigen, Daniel M.; Wong, Jessie J.; Cucciare, Michael A.
2017-01-01
There is a need to understand the determinants of both substance use and criminal activity in rural areas in order to design appropriate treatment interventions for these linked problems. The present study drew on a predominant model used to assess and treat offenders -- the Risk-Need-Responsivity (RNR) model -- to examine risk factors for substance use and criminal activity in a rural drug using sample. This study extends the RNR model’s focus on offenders to assessing rural-dwelling individuals using stimulants (N=462). We examined substance use and criminal justice outcomes at 6-month (91%) and 3-year (79%) follow-ups, and used Generalized Estimating Equations to examine the extent to which RNR criminogenic need factors at baseline predicted outcomes at follow-ups. Substance use and criminal justice outcomes improved at six months, and even more at three years, post-baseline. As expected, higher risk was associated with poorer outcomes. Antisocial personality patterns and procriminal attitudes at baseline predicted poorer legal and drug outcomes measured at subsequent follow-ups. In contrast, less connection to antisocial others and fewer work difficulties predicted lower alcohol problem severity, but more frequent alcohol use. Engagement in social-recreational activities was associated with fewer subsequent arrests and less severe alcohol and drug problems. The RNR model’s criminogenic need factors predicted drug use and crime-related outcomes among rural residents. Services adapted to rural settings that target these factors, such as telehealth and other technology-based resources, may hasten improvement on both types of outcomes among drug users. PMID:29051795
A Laboratory-Based Test of the Relation between Adolescent Alcohol Use and Panic-Relevant Responding
Blumenthal, Heidemarie; Cloutier, Renee M.; Zamboanga, Byron L.; Bunaciu, Liviu; Knapp, Ashley A.
2015-01-01
A burgeoning literature supports a link between alcohol use and panic-spectrum problems (e.g., panic attacks, disorder) among adolescents, but the direction of influence has yet to be properly examined. From a theoretical perspective, panic-spectrum problems may increase risk for problematic drinking via affect regulation efforts (e.g., self-medication), and problematic consumption also may increase or initiate panic-relevant responding (e.g., learning or kindling models). The objective of the current investigation was to examine the role of prior alcohol use in predicting panic-relevant responding, as well as panic symptom history in predicting the desire to consume alcohol, in the context of either a voluntary hyperventilation or a low-arousal task. Participants were community-recruited adolescents aged 12-17 years (n = 92, Mage = 15.42, SD = 1.51; 39.1% girls). Results indicated that prior alcohol use predicted panic-relevant responding among those undergoing the hyperventilation task (but not the low-arousal task), and that this finding was robust to the inclusion of theoretically-relevant covariates (i.e. age, sex, negative affectivity). However, panic symptom history did not predict the desire to consume alcohol as a function of either the hyperventilation or low-arousal condition. This work sheds further light on the nature of the relation between panic-spectrum problems and problematic alcohol use in adolescence. Specifically, the current findings suggest that frequent alcohol use may increase panic vulnerability among adolescents, whereas acute panic symptoms may not elicit the immediate (self-reported) desire to drink. PMID:26053320
Accuracy test for link prediction in terms of similarity index: The case of WS and BA models
NASA Astrophysics Data System (ADS)
Ahn, Min-Woo; Jung, Woo-Sung
2015-07-01
Link prediction is a technique that uses the topological information in a given network to infer the missing links in it. Since past research on link prediction has primarily focused on enhancing performance for given empirical systems, negligible attention has been devoted to link prediction with regard to network models. In this paper, we thus apply link prediction to two network models: The Watts-Strogatz (WS) model and Barabási-Albert (BA) model. We attempt to gain a better understanding of the relation between accuracy and each network parameter (mean degree, the number of nodes and the rewiring probability in the WS model) through network models. Six similarity indices are used, with precision and area under the ROC curve (AUC) value as the accuracy metrics. We observe a positive correlation between mean degree and accuracy, and size independence of the AUC value.
Minkiewicz, Piotr; Darewicz, Małgorzata; Iwaniak, Anna; Bucholska, Justyna; Starowicz, Piotr; Czyrko, Emilia
2016-01-01
Internet databases of small molecules, their enzymatic reactions, and metabolism have emerged as useful tools in food science. Database searching is also introduced as part of chemistry or enzymology courses for food technology students. Such resources support the search for information about single compounds and facilitate the introduction of secondary analyses of large datasets. Information can be retrieved from databases by searching for the compound name or structure, annotating with the help of chemical codes or drawn using molecule editing software. Data mining options may be enhanced by navigating through a network of links and cross-links between databases. Exemplary databases reviewed in this article belong to two classes: tools concerning small molecules (including general and specialized databases annotating food components) and tools annotating enzymes and metabolism. Some problems associated with database application are also discussed. Data summarized in computer databases may be used for calculation of daily intake of bioactive compounds, prediction of metabolism of food components, and their biological activity as well as for prediction of interactions between food component and drugs. PMID:27929431
Minkiewicz, Piotr; Darewicz, Małgorzata; Iwaniak, Anna; Bucholska, Justyna; Starowicz, Piotr; Czyrko, Emilia
2016-12-06
Internet databases of small molecules, their enzymatic reactions, and metabolism have emerged as useful tools in food science. Database searching is also introduced as part of chemistry or enzymology courses for food technology students. Such resources support the search for information about single compounds and facilitate the introduction of secondary analyses of large datasets. Information can be retrieved from databases by searching for the compound name or structure, annotating with the help of chemical codes or drawn using molecule editing software. Data mining options may be enhanced by navigating through a network of links and cross-links between databases. Exemplary databases reviewed in this article belong to two classes: tools concerning small molecules (including general and specialized databases annotating food components) and tools annotating enzymes and metabolism. Some problems associated with database application are also discussed. Data summarized in computer databases may be used for calculation of daily intake of bioactive compounds, prediction of metabolism of food components, and their biological activity as well as for prediction of interactions between food component and drugs.
Interpretation bias and anxiety in childhood: stability, specificity and longitudinal associations.
Creswell, Cathy; O'Connor, Thomas G
2011-03-01
Biases in the interpretation of ambiguous material are central to cognitive models of anxiety; however, understanding of the association between interpretation and anxiety in childhood is limited. To address this, a prospective investigation of the stability and specificity of anxious cognitions and anxiety and the relationship between these factors was conducted. Sixty-five children (10-11 years) from a community sample completed measures of self-reported anxiety, depression, and conduct problems, and responded to ambiguous stories at three time points over one-year. Individual differences in biases in interpretation of ambiguity (specifically "anticipated distress" and "threat interpretation") were stable over time. Furthermore, anticipated distress and threat interpretation were specifically associated with anxiety symptoms. Distress anticipation predicted change in anxiety symptoms over time. In contrast, anxiety scores predicted change in threat interpretation over time. The results suggest that different cognitive constructs may show different longitudinal links with anxiety. These preliminary findings extend research and theory on anxious cognitions and their link with anxiety in children, and suggest that these cognitive processes may be valuable targets for assessment and intervention.
Oxytonergic circuitry sustains and enables creative cognition in humans
Baas, Matthijs; Roskes, Marieke; Sligte, Daniel J.; Ebstein, Richard P.; Chew, Soo Hong; Tong, Terry; Jiang, Yushi; Mayseless, Naama; Shamay-Tsoory, Simone G.
2014-01-01
Creativity enables humans to adapt flexibly to changing circumstances, to manage complex social relations and to survive and prosper through social, technological and medical innovations. In humans, chronic, trait-based as well as temporary, state-based approach orientation has been linked to increased capacity for divergent rather than convergent thinking, to more global and holistic processing styles and to more original ideation and creative problem solving. Here, we link creative cognition to oxytocin, a hypothalamic neuropeptide known to up-regulate approach orientation in both animals and humans. Study 1 (N = 492) showed that plasma oxytocin predicts novelty-seeking temperament. Study 2 (N = 110) revealed that genotype differences in a polymorphism in the oxytocin receptor gene rs1042778 predicted creative ideation, with GG/GT-carriers being more original than TT-carriers. Using double-blind placebo-controlled between-subjects designs, Studies 3–6 (N = 191) finally showed that intranasal oxytocin (vs matching placebo) reduced analytical reasoning, and increased holistic processing, divergent thinking and creative performance. We conclude that the oxytonergic circuitry sustains and enables the day-to-day creativity humans need for survival and prosperity and discuss implications. PMID:23863476
Hitchings, Julia E.; Spoth, Richard L.
2010-01-01
Conduct problems are strong positive predictors of substance use and problem substance use among teens, whereas predictive associations of depressed mood with these outcomes are mixed. Conduct problems and depressed mood often co-occur, and such co-occurrence may heighten risk for negative outcomes. Thus, this study examined the interaction of conduct problems and depressed mood at age 11 in relation to substance use and problem use at age 18, and possible mediation through peer substance use at age 16. Analyses of multirater longitudinal data collected from 429 rural youths (222 girls) and their families were conducted using a methodology for testing latent variable interactions. The link between the conduct problems X depressed mood interaction and adolescent substance use was negative and statistically significant. Unexpectedly, positive associations of conduct problems with substance use were stronger at lower levels of depressed mood. A significant negative interaction in relation to peer substance use also was observed, and the estimated indirect effect of the interaction on adolescent use through peer use as a mediator was statistically significant. Findings illustrate the complexity of multiproblem youth. PMID:18455886
Yaros, Anna; Lochman, John E.; Wells, Karen C.
2015-01-01
Aggression among youth is public health problem that is often studied in the context of how youth interpret social information. Social cognitive factors, especially hostile attribution biases, have been identified as risk factors for the development of youth aggression, particularly across the transition to middle school. Parental behaviors, including parental aggression to children in the form of corporal punishment and other aggressive behavior, have also been linked to aggressive behavior in children at these ages. Despite the important role played by these two risk factors, the connection between the two has not been fully studied in the literature. This study examined the link between parental aggression and children’ hostile attributions longitudinally among a diverse sample of 123 boys as they entered middle school. Results support acceptance of a model in which parental aggression to children prior to entering middle school predicted children’s hostile attributions after the transition to middle school above and beyond that which was predicted by previous levels of hostile attributions. As expected, hostile attributions also predicted change in parent- and teacher-rated child aggression. These findings provides important evidence of the role that parental behavior plays in youth social cognition at this critical age, which has implications for understanding the development of aggressive behavior. PMID:27647945
Fukunishi, Yoshifumi
2010-01-01
For fragment-based drug development, both hit (active) compound prediction and docking-pose (protein-ligand complex structure) prediction of the hit compound are important, since chemical modification (fragment linking, fragment evolution) subsequent to the hit discovery must be performed based on the protein-ligand complex structure. However, the naïve protein-compound docking calculation shows poor accuracy in terms of docking-pose prediction. Thus, post-processing of the protein-compound docking is necessary. Recently, several methods for the post-processing of protein-compound docking have been proposed. In FBDD, the compounds are smaller than those for conventional drug screening. This makes it difficult to perform the protein-compound docking calculation. A method to avoid this problem has been reported. Protein-ligand binding free energy estimation is useful to reduce the procedures involved in the chemical modification of the hit fragment. Several prediction methods have been proposed for high-accuracy estimation of protein-ligand binding free energy. This paper summarizes the various computational methods proposed for docking-pose prediction and their usefulness in FBDD.
Higher order approximation to the Hill problem dynamics about the libration points
NASA Astrophysics Data System (ADS)
Lara, Martin; Pérez, Iván L.; López, Rosario
2018-06-01
An analytical solution to the Hill problem Hamiltonian expanded about the libration points has been obtained by means of perturbation techniques. In order to compute the higher orders of the perturbation solution that are needed to capture all the relevant periodic orbits originated from the libration points within a reasonable accuracy, the normalization is approached in complex variables. The validity of the solution extends to energy values considerably far away from that of the libration points and, therefore, can be used in the computation of Halo orbits as an alternative to the classical Lindstedt-Poincaré approach. Furthermore, the theory correctly predicts the existence of the two-lane bridge of periodic orbits linking the families of planar and vertical Lyapunov orbits.
Ceramic component reliability with the restructured NASA/CARES computer program
NASA Technical Reports Server (NTRS)
Powers, Lynn M.; Starlinger, Alois; Gyekenyesi, John P.
1992-01-01
The Ceramics Analysis and Reliability Evaluation of Structures (CARES) integrated design program on statistical fast fracture reliability and monolithic ceramic components is enhanced to include the use of a neutral data base, two-dimensional modeling, and variable problem size. The data base allows for the efficient transfer of element stresses, temperatures, and volumes/areas from the finite element output to the reliability analysis program. Elements are divided to insure a direct correspondence between the subelements and the Gaussian integration points. Two-dimensional modeling is accomplished by assessing the volume flaw reliability with shell elements. To demonstrate the improvements in the algorithm, example problems are selected from a round-robin conducted by WELFEP (WEakest Link failure probability prediction by Finite Element Postprocessors).
NASA Technical Reports Server (NTRS)
Orasanu, Judith
1991-01-01
Aircrew effectiveness in coping with emergencies has been linked to captain's personality profile. The present study analyzed cockpit communication during simulated flight to examine the relation between captains' discourse strategies, personality profiles, and crew performance. Positive Instrumental/Expressive captains and Instrumental-Negative captains used very similar communication strategies and their crews made few errors. Their talk was distinguished by high levels of planning and strategizing, gathering information, predicting/alerting, and explaining, especially during the emergency flight phase. Negative-Expressive captains talked less overall, and engaged in little problem solving talk, even during emergencies. Their crews made many errors. Findings support the theory that high crew performance results when captains use language to build shared mental models for problem situations.
Infant pathways to externalizing behavior: evidence of Genotype x Environment interaction.
Leve, Leslie D; Kerr, David C R; Shaw, Daniel; Ge, Xiaojia; Neiderhiser, Jenae M; Scaramella, Laura V; Reid, John B; Conger, Rand; Reiss, David
2010-01-01
To further the understanding of the effects of early experiences, 9-month-old infants were observed during a frustration task. The analytical sample was composed of 348 linked triads of participants (adoptive parents, adopted child, and birth parent[s]) from a prospective adoption study. It was hypothesized that genetic risk for externalizing problems and affect dysregulation in the adoptive parents would independently and interactively predict a known precursor to externalizing problems: heightened infant attention to frustrating events. Results supported the moderation hypotheses involving adoptive mother affect dysregulation: Infants at genetic risk showed heightened attention to frustrating events only when the adoptive mother had higher levels of anxious and depressive symptoms. The Genotype x Environment interaction pattern held when substance use during pregnancy was considered.
NASA Astrophysics Data System (ADS)
Jones, A. S.; Andales, A.; McGovern, C.; Smith, G. E. B.; David, O.; Fletcher, S. J.
2017-12-01
US agricultural and Govt. lands have a unique co-dependent relationship, particularly in the Western US. More than 30% of all irrigated US agricultural output comes from lands sustained by the Ogallala Aquifer in the western Great Plains. Six US Forest Service National Grasslands reside within the aquifer region, consisting of over 375,000 ha (3,759 km2) of USFS managed lands. Likewise, National Forest lands are the headwaters to many intensive agricultural regions. Our Ogallala Aquifer team is enhancing crop irrigation decision tools with predictive weather and remote sensing data to better manage water for irrigated crops within these regions. An integrated multi-model software framework is used to link irrigation decision tools, resulting in positive management benefits on natural water resources. Teams and teams-of-teams can build upon these multi-disciplinary multi-faceted modeling capabilities. For example, the CSU Catalyst for Innovative Partnerships program has formed a new multidisciplinary team that will address "Rural Wealth Creation" focusing on the many integrated links between economic, agricultural production and management, natural resource availabilities, and key social aspects of govt. policy recommendations. By enhancing tools like these with predictive weather and other related data (like in situ measurements, hydrologic models, remotely sensed data sets, and (in the near future) linking to agro-economic and life cycle assessment models) this work demonstrates an integrated data-driven future vision of inter-meshed dynamic systems that can address challenging multi-system problems. We will present the present state of the work and opportunities for future involvement.
Ide, Jaime S; Zhornitsky, Simon; Hu, Sien; Zhang, Sheng; Krystal, John H; Li, Chiang-Shan R
2017-01-01
Alcohol expectancy and impulsivity are implicated in alcohol misuse. However, how these two risk factors interact to determine problem drinking and whether men and women differ in these risk processes remain unclear. In 158 social drinkers (86 women) assessed for Alcohol Use Disorder Identification Test (AUDIT), positive alcohol expectancy, and Barratt impulsivity, we examined sex differences in these risk processes. Further, with structural brain imaging, we examined the neural bases underlying the relationship between these risk factors and problem drinking. The results of general linear modeling showed that alcohol expectancy best predicted problem drinking in women, whereas in men as well as in the combined group alcohol expectancy and impulsivity interacted to best predict problem drinking. Alcohol expectancy was associated with decreased gray matter volume (GMV) of the right posterior insula in women and the interaction of alcohol expectancy and impulsivity was associated with decreased GMV of the left thalamus in women and men combined and in men alone, albeit less significantly. These risk factors mediated the correlation between GMV and problem drinking. Conversely, models where GMV resulted from problem drinking were not supported. These new findings reveal distinct psychological factors that dispose men and women to problem drinking. Although mediation analyses did not determine a causal link, GMV reduction in the insula and thalamus may represent neural phenotype of these risk processes rather than the consequence of alcohol consumption in non-dependent social drinkers. The results add to the alcohol imaging literature which has largely focused on dependent individuals and help elucidate alterations in brain structures that may contribute to the transition from social to habitual drinking.
Predicting missing links and identifying spurious links via likelihood analysis
NASA Astrophysics Data System (ADS)
Pan, Liming; Zhou, Tao; Lü, Linyuan; Hu, Chin-Kun
2016-03-01
Real network data is often incomplete and noisy, where link prediction algorithms and spurious link identification algorithms can be applied. Thus far, it lacks a general method to transform network organizing mechanisms to link prediction algorithms. Here we use an algorithmic framework where a network’s probability is calculated according to a predefined structural Hamiltonian that takes into account the network organizing principles, and a non-observed link is scored by the conditional probability of adding the link to the observed network. Extensive numerical simulations show that the proposed algorithm has remarkably higher accuracy than the state-of-the-art methods in uncovering missing links and identifying spurious links in many complex biological and social networks. Such method also finds applications in exploring the underlying network evolutionary mechanisms.
Predicting missing links and identifying spurious links via likelihood analysis
Pan, Liming; Zhou, Tao; Lü, Linyuan; Hu, Chin-Kun
2016-01-01
Real network data is often incomplete and noisy, where link prediction algorithms and spurious link identification algorithms can be applied. Thus far, it lacks a general method to transform network organizing mechanisms to link prediction algorithms. Here we use an algorithmic framework where a network’s probability is calculated according to a predefined structural Hamiltonian that takes into account the network organizing principles, and a non-observed link is scored by the conditional probability of adding the link to the observed network. Extensive numerical simulations show that the proposed algorithm has remarkably higher accuracy than the state-of-the-art methods in uncovering missing links and identifying spurious links in many complex biological and social networks. Such method also finds applications in exploring the underlying network evolutionary mechanisms. PMID:26961965
Link prediction in the network of global virtual water trade
NASA Astrophysics Data System (ADS)
Tuninetti, Marta; Tamea, Stefania; Laio, Francesco; Ridolfi, Luca
2016-04-01
Through the international food-trade, water resources are 'virtually' transferred from the country of production to the country of consumption. The international food-trade, thus, implies a network of virtual water flows from exporting to importing countries (i.e., nodes). Given the dynamical behavior of the network, where food-trade relations (i.e., links) are created and dismissed every year, link prediction becomes a challenge. In this study, we propose a novel methodology for link prediction in the virtual water network. The model aims at identifying the main factors (among 17 different variables) driving the creation of a food-trade relation between any two countries, along the period between 1986 and 2011. Furthermore, the model can be exploited to investigate the network configuration in the future, under different possible (climatic and demographic) scenarios. The model grounds the existence of a link between any two nodes on the link weight (i.e., the virtual water flow): a link exists when the nodes exchange a minimum (fixed) volume of virtual water. Starting from a set of potential links between any two nodes, we fit the associated virtual water flows (both the real and the null ones) by means of multivariate linear regressions. Then, links with estimated flows higher than a minimum value (i.e., threshold) are considered active-links, while the others are non-active ones. The discrimination between active and non-active links through the threshold introduces an error (called link-prediction error) because some real links are lost (i.e., missed links) and some non-existing links (i.e., spurious links) are inevitably introduced in the network. The major drivers are those significantly minimizing the link-prediction error. Once the structure of the unweighted virtual water network is known, we apply, again, linear regressions to assess the major factors driving the fluxes traded along (modelled) active-links. Results indicate that, on the one hand, population and fertilizer use, together with link properties (such as the distance between nodes), are the major factors driving the links creation; on the other hand, population, distance, and gross domestic product are essential to model the flux entity. The results are promising since the model is able to correctly predict the 85% of the 16422 food-trade links (15% are missed), by spuriously adding to the real network only the 5% of non-existing links. The link-prediction error, evaluated as the sum of the percentage of missed and spurious links, is around 20% and it is constant over the study period. Only the 0.01% of the global virtual water flow is traded along missed links and an even lower flow is added by the spurious links (0.003%).
Hippocampal-neocortical functional reorganization underlies children's cognitive development
Qin, Shaozheng; Cho, Soohyun; Chen, Tianwen; Rosenberg-Lee, Miriam; Geary, David C.; Menon, Vinod
2014-01-01
The importance of the hippocampal system for rapid learning and memory is well recognized, but its contributions to a cardinal feature of children's cognitive development – the transition from procedure-based to memory-based problem solving strategies – are unknown. Here we show that the hippocampal system is pivotal to this strategic transition. Longitudinal fMRI in children, ages 7 to 9, revealed that the transition from use of counting to memory-based retrieval parallels increased hippocampal and decreased prefrontal-parietal engagement during arithmetic problem solving. Critically, longitudinal improvements in retrieval strategy use were predicted by increased hippocampal-neocortical functional connectivity. Beyond childhood, retrieval strategy use continued to improve through adolescence into adulthood, and was associated with decreased activation but more stable inter-problem representations in the hippocampus. Our findings provide novel insights into the dynamic role of the hippocampus in the maturation of memory-based problem solving, and establish a critical link between hippocampal-neocortical reorganization and children's cognitive development. PMID:25129076
Working Toward a Healthy Planet
NASA Technical Reports Server (NTRS)
Maynard, Nancy G.
2003-01-01
Using information from NASA s Earth Science Public Health Applications Program, Dr. Maynard will address how remote sensing data and associated technologies can be used toward a better understanding of the links among human health, the environment and weather/climate - and, how this increased understanding plus improved information sharing can empower local health and environmental decision-makers to better predict climate-related health problems, take preventive measures, and improve response actions. Remotely-sensed data and observations are providing powerful new tools for addressing climate and environment-related human health problems through increased capabilities for monitoring and surveillance of parameters useful to such problems as infectious and vector-borne diseases, air and water quality, harmful algal blooms, UV radiation, contaminant and pathogen transport in air and water, and thermal stress. NASA s multi-disciplinary scientific team is demonstrating how satellites from their unique vantage point in space can serve as sentinels for weather, climate, and health problems through studies on asthma, malaria, Rift Valley Fever, Asian and African dust, and West Nile Virus
Cannabis Problem Experiences Among Users of the Tobacco-Cannabis Combination Known As Blunts
Fairman, Brian J.
2015-01-01
Background In most of the world, cannabis smokers mix loose tobacco inside a joint, pipe, spliff, or cone. More recently, a ‘blunt’ formulation combines these two drugs by inserting cannabis into a hollowed-out cigar. Epidemiological research linking simultaneous use of these two drugs and the development of cannabis use disorders (CUD) remains unclear. This study estimates associations linking blunt smoking with levels and subtypes of cannabis problems. Methods Cross-sectional data on 27,767 past-year cannabis users were analyzed from the US National Survey on Drug Use and Health (NSDUH) conducted from 2009–2012. Ten self-reported items of DSM-IV CUD features elicited a single latent trait of cannabis problem (CP) severity, which was then regressed on past-year blunt smoking and past-month blunt frequency measures within the context of a conceptual model. Differential item functioning (DIF) analysis evaluated potential bias in CP feature response by blunt smoking history. Results Past-year blunt smoking was associated with higher CP severity compared to cannabis users who did not smoke blunts. Days of blunt smoking in the past month also predicted higher CP severity than less frequent blunt use. Those smoking blunts experienced more subjectively felt tolerance and having spent more time obtaining or using cannabis, but were less likely to experience other problems, even at the same level of CP severity. Conclusions These findings suggest smoking blunts might promote the development of problematic cannabis use. Responses to cannabis problems differed by history of blunt smoking, possibly implicating an influence of tobacco on measurement of cannabis use disorders. PMID:25746234
Cannabis problem experiences among users of the tobacco-cannabis combination known as blunts.
Fairman, Brian J
2015-05-01
In most of the world, cannabis smokers mix loose tobacco inside a joint, pipe, spliff, or cone. More recently, a 'blunt' formulation combines these two drugs by inserting cannabis into a hollowed-out cigar. Epidemiological research linking simultaneous use of these two drugs and the development of cannabis use disorders (CUD) remains unclear. This study estimates associations linking blunt smoking with levels and subtypes of cannabis problems. Cross-sectional data on 27,767 past-year cannabis users were analyzed from the US National Survey on Drug Use and Health (NSDUH) conducted from 2009 to 2012. Ten self-reported items of DSM-IV CUD features elicited a single latent trait of cannabis problem (CP) severity, which was then regressed on past-year blunt smoking and past-month blunt frequency measures within the context of a conceptual model. Differential item functioning (DIF) analysis evaluated potential bias in CP feature response by blunt smoking history. Past-year blunt smoking was associated with higher CP severity compared to cannabis users who did not smoke blunts. Days of blunt smoking in the past month also predicted higher CP severity than less frequent blunt use. Those smoking blunts experienced more subjectively felt tolerance and having spent more time obtaining or using cannabis, but were less likely to experience other problems, even at the same level of CP severity. These findings suggest smoking blunts might promote the development of problematic cannabis use. Responses to cannabis problems differed by history of blunt smoking, possibly implicating an influence of tobacco on measurement of cannabis use disorders. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Predicting missing links in complex networks based on common neighbors and distance
Yang, Jinxuan; Zhang, Xiao-Dong
2016-01-01
The algorithms based on common neighbors metric to predict missing links in complex networks are very popular, but most of these algorithms do not account for missing links between nodes with no common neighbors. It is not accurate enough to reconstruct networks by using these methods in some cases especially when between nodes have less common neighbors. We proposed in this paper a new algorithm based on common neighbors and distance to improve accuracy of link prediction. Our proposed algorithm makes remarkable effect in predicting the missing links between nodes with no common neighbors and performs better than most existing currently used methods for a variety of real-world networks without increasing complexity. PMID:27905526
Revisiting competition in a classic model system using formal links between theory and data.
Hart, Simon P; Burgin, Jacqueline R; Marshall, Dustin J
2012-09-01
Formal links between theory and data are a critical goal for ecology. However, while our current understanding of competition provides the foundation for solving many derived ecological problems, this understanding is fractured because competition theory and data are rarely unified. Conclusions from seminal studies in space-limited benthic marine systems, in particular, have been very influential for our general understanding of competition, but rely on traditional empirical methods with limited inferential power and compatibility with theory. Here we explicitly link mathematical theory with experimental field data to provide a more sophisticated understanding of competition in this classic model system. In contrast to predictions from conceptual models, our estimates of competition coefficients show that a dominant space competitor can be equally affected by interspecific competition with a poor competitor (traditionally defined) as it is by intraspecific competition. More generally, the often-invoked competitive hierarchies and intransitivities in this system might be usefully revisited using more sophisticated empirical and analytical approaches.
Chen, Qing; Zhang, Jinxiu; Hu, Ze
2017-01-01
This article investigates the dynamic topology control problem of satellite cluster networks (SCNs) in Earth observation (EO) missions by applying a novel metric of stability for inter-satellite links (ISLs). The properties of the periodicity and predictability of satellites’ relative position are involved in the link cost metric which is to give a selection criterion for choosing the most reliable data routing paths. Also, a cooperative work model with reliability is proposed for the situation of emergency EO missions. Based on the link cost metric and the proposed reliability model, a reliability assurance topology control algorithm and its corresponding dynamic topology control (RAT) strategy are established to maximize the stability of data transmission in the SCNs. The SCNs scenario is tested through some numeric simulations of the topology stability of average topology lifetime and average packet loss rate. Simulation results show that the proposed reliable strategy applied in SCNs significantly improves the data transmission performance and prolongs the average topology lifetime. PMID:28241474
A probabilistic framework to infer brain functional connectivity from anatomical connections.
Deligianni, Fani; Varoquaux, Gael; Thirion, Bertrand; Robinson, Emma; Sharp, David J; Edwards, A David; Rueckert, Daniel
2011-01-01
We present a novel probabilistic framework to learn across several subjects a mapping from brain anatomical connectivity to functional connectivity, i.e. the covariance structure of brain activity. This prediction problem must be formulated as a structured-output learning task, as the predicted parameters are strongly correlated. We introduce a model selection framework based on cross-validation with a parametrization-independent loss function suitable to the manifold of covariance matrices. Our model is based on constraining the conditional independence structure of functional activity by the anatomical connectivity. Subsequently, we learn a linear predictor of a stationary multivariate autoregressive model. This natural parameterization of functional connectivity also enforces the positive-definiteness of the predicted covariance and thus matches the structure of the output space. Our results show that functional connectivity can be explained by anatomical connectivity on a rigorous statistical basis, and that a proper model of functional connectivity is essential to assess this link.
Van Hulle, Carol A; Moore, Mollie N; Lemery-Chalfant, Kathryn; Goldsmith, H Hill; Brooker, Rebecca J
2017-08-01
Although a robust literature has linked stable, high levels of fear across childhood to increased risk for anxiety problems, less is known about alternative pathways to anxiety. We tested two putatively normative developmental pathways of early fearfulness for their distinct associations with behavioral (anxiety-related behaviors and symptoms) and biological (diurnal cortisol) markers of anxiety risk in middle childhood in a community-based sample (n = 107). Steeper increases in fear from 6 to 36 months predicted more parent-reported anxiety symptoms at age 8 years. In addition, children who exhibited steep increases in fear during infancy were overrepresented among children with diagnoses of separation anxiety disorder at age 8 years. Finally, we showed that steeper increases in fearfulness in infancy predicted flatter slopes of diurnal cortisol at age 8 years for girls. Thus, differences in stranger fear across infancy may indicate varying degrees of risk for anxious behaviors in later childhood.
Najmi, Sadia; Bureau, Jean-Francois; Chen, Diyu; Lyons-Ruth, Karlen
2009-12-01
: The Personal Attitude Scale (PAS; Hooley, 2000) is a method that is under development for identifying individuals high in Expressed Emotion based on personality traits of inflexibility, intolerance, and norm-forming. In the current study, the goal was to measure the association between this maternal attitudinal inflexibility, early hostile or disrupted mother-infant interactions, and hostile-aggressive behavior problems in the child. In a prospective longitudinal study of 76 low-income mothers and their infants, it was predicted that maternal PAS scores, assessed at child age 20, would be related to difficulties in early observed mother-infant interaction and to hostile-aggressive behavioral difficulties in the child. Results indicated that maternal difficulties in interacting with the infant in the laboratory were associated with maternal PAS scores assessed 20 years later. Hostile-aggressive behavior problems in the child at age five were also predictive of PAS scores of mothers. However, contrary to prediction, these behavior problems did not mediate the association between mother-infant interaction difficulties and maternal PAS scores, indicating that the child's hostile-aggressive behavior problems did not produce the link between quality of early interaction and later maternal attitudinal inflexibility. The current results validate the PAS against observable mother-child interactions and child hostile-aggressive behavior problems and indicate the importance of future work investigating the maternal attitudes that are associated with, and may potentially precede, parent-infant interactive difficulties. These findings regarding the inflexible attitudes of mothers whose interactions with their infants are also disrupted have important clinical implications. First, once the stability of the PAS has been established, this measure may offer a valuable screening tool for the prenatal identification of parents at risk for difficult interactions with their children. Second, it suggests routes for more cognitive interventions around helping less flexible parents shift perspectives to better take account of their child's outlooks and needs.
ERIC Educational Resources Information Center
Yip, Vania T.; Ang, Rebecca P.; Ooi, Yoon Phaik; Fung, Daniel S. S.; Mehrotra, Kala; Sung, Min; Lim, Choon Guan
2013-01-01
Background: The high prevalence of attention problems in children warrants concern, as it is a risk factor for internalizing and externalizing problems. There lies a need to understand possible factors that may mediate this link so that interventions may be targeted to alleviate these mediators and interrupt the link between attention problems and…
Efficient network disintegration under incomplete information: the comic effect of link prediction
NASA Astrophysics Data System (ADS)
Tan, Suo-Yi; Wu, Jun; Lü, Linyuan; Li, Meng-Jun; Lu, Xin
2016-03-01
The study of network disintegration has attracted much attention due to its wide applications, including suppressing the epidemic spreading, destabilizing terrorist network, preventing financial contagion, controlling the rumor diffusion and perturbing cancer networks. The crux of this matter is to find the critical nodes whose removal will lead to network collapse. This paper studies the disintegration of networks with incomplete link information. An effective method is proposed to find the critical nodes by the assistance of link prediction techniques. Extensive experiments in both synthetic and real networks suggest that, by using link prediction method to recover partial missing links in advance, the method can largely improve the network disintegration performance. Besides, to our surprise, we find that when the size of missing information is relatively small, our method even outperforms than the results based on complete information. We refer to this phenomenon as the “comic effect” of link prediction, which means that the network is reshaped through the addition of some links that identified by link prediction algorithms, and the reshaped network is like an exaggerated but characteristic comic of the original one, where the important parts are emphasized.
Efficient network disintegration under incomplete information: the comic effect of link prediction.
Tan, Suo-Yi; Wu, Jun; Lü, Linyuan; Li, Meng-Jun; Lu, Xin
2016-03-10
The study of network disintegration has attracted much attention due to its wide applications, including suppressing the epidemic spreading, destabilizing terrorist network, preventing financial contagion, controlling the rumor diffusion and perturbing cancer networks. The crux of this matter is to find the critical nodes whose removal will lead to network collapse. This paper studies the disintegration of networks with incomplete link information. An effective method is proposed to find the critical nodes by the assistance of link prediction techniques. Extensive experiments in both synthetic and real networks suggest that, by using link prediction method to recover partial missing links in advance, the method can largely improve the network disintegration performance. Besides, to our surprise, we find that when the size of missing information is relatively small, our method even outperforms than the results based on complete information. We refer to this phenomenon as the "comic effect" of link prediction, which means that the network is reshaped through the addition of some links that identified by link prediction algorithms, and the reshaped network is like an exaggerated but characteristic comic of the original one, where the important parts are emphasized.
Efficient network disintegration under incomplete information: the comic effect of link prediction
Tan, Suo-Yi; Wu, Jun; Lü, Linyuan; Li, Meng-Jun; Lu, Xin
2016-01-01
The study of network disintegration has attracted much attention due to its wide applications, including suppressing the epidemic spreading, destabilizing terrorist network, preventing financial contagion, controlling the rumor diffusion and perturbing cancer networks. The crux of this matter is to find the critical nodes whose removal will lead to network collapse. This paper studies the disintegration of networks with incomplete link information. An effective method is proposed to find the critical nodes by the assistance of link prediction techniques. Extensive experiments in both synthetic and real networks suggest that, by using link prediction method to recover partial missing links in advance, the method can largely improve the network disintegration performance. Besides, to our surprise, we find that when the size of missing information is relatively small, our method even outperforms than the results based on complete information. We refer to this phenomenon as the “comic effect” of link prediction, which means that the network is reshaped through the addition of some links that identified by link prediction algorithms, and the reshaped network is like an exaggerated but characteristic comic of the original one, where the important parts are emphasized. PMID:26960247
Shek, Daniel T. L.; Zhu, Xiaoqin
2018-01-01
Based on the six-wave data collected from Grade 7 to Grade 12 students (N = 3,328 at Wave 1), this pioneer study examined the development of problem behaviors (risk and delinquent behavior and problem behavioral intention) and the predictors (moral competence and spirituality) among adolescents in Hong Kong. Individual growth curve models revealed that while risk and delinquent behavior accelerated and then slowed down in the high school years, adolescent problem behavioral intention slightly accelerated over time. After controlling the background socio-demographic factors, moral competence and spirituality were negatively associated with risk and delinquent behavior as well as problem behavioral intention across all waves as predicted. Regarding the rate of change in the outcome measures, while the initial level of spirituality was positively linked to the growth rate of risk and delinquent behavior, the initial level of moral competence was negatively associated with the growth rate of problem behavioral intention. The theoretical and practical implications of the present findings are discussed with reference to the role of moral competence and spirituality in the development of adolescent problem behavior. PMID:29651269
Shek, Daniel T L; Zhu, Xiaoqin
2018-01-01
Based on the six-wave data collected from Grade 7 to Grade 12 students ( N = 3,328 at Wave 1), this pioneer study examined the development of problem behaviors (risk and delinquent behavior and problem behavioral intention) and the predictors (moral competence and spirituality) among adolescents in Hong Kong. Individual growth curve models revealed that while risk and delinquent behavior accelerated and then slowed down in the high school years, adolescent problem behavioral intention slightly accelerated over time. After controlling the background socio-demographic factors, moral competence and spirituality were negatively associated with risk and delinquent behavior as well as problem behavioral intention across all waves as predicted. Regarding the rate of change in the outcome measures, while the initial level of spirituality was positively linked to the growth rate of risk and delinquent behavior, the initial level of moral competence was negatively associated with the growth rate of problem behavioral intention. The theoretical and practical implications of the present findings are discussed with reference to the role of moral competence and spirituality in the development of adolescent problem behavior.
Hemphill, Sheryl A; Kotevski, Aneta; Heerde, Jessica A
2015-02-01
To investigate associations between Grade 9 and 10 cyber-bullying perpetration and victimization and Grade 11 problem behavior and mental health problems after controlling for risk factors for these outcomes in the analyses. The sample comprised 927 students from Victoria, Australia who completed a modified version of the self-report Communities That Care Youth Survey in Grades 9-11 to report on risk factors, traditional and cyber-bullying perpetration and victimization, problem behavior, and mental health. Complete data on over 650 participants were analyzed. Five per cent of Grade 9 and 10 students reported cyber-bullying perpetration only, 6-8% reported victimization only, and 8-9% both cyber-bullied others and were cyber-bullied. Results showed that cyber-bullying others in Grade 10 was associated with theft in Grade 11, cyber-victimization in Grade 10 was linked with Grade 11 depressive symptoms, and Grade 10 cyber-bullying perpetration and victimization combined predicted Grade 11 school suspension and binge drinking. Prevention approaches that target traditional and cyber-bullying, and established risk factors are necessary. Such multi-faceted programs may also reduce problem behavior and mental health problems.
Childhood maltreatment and adulthood poor sleep quality: a longitudinal study.
Abajobir, Amanuel A; Kisely, Steve; Williams, Gail; Strathearn, Lane; Najman, Jake M
2017-08-01
Available evidence from cross-sectional studies suggests that childhood maltreatment may be associated with a range of sleep disorders. However, these studies have not controlled for potential individual-, familial- and environmental-level confounders. To determine the association between childhood maltreatment and lower sleep quality after adjusting for potential confounders. Data for the present study were obtained from a pre-birth cohort study of 3778 young adults (52.6% female) of the Mater Hospital-University of Queensland Study of Pregnancy follow up at a mean age of 20.6 years. The Mater Hospital-University of Queensland Study of Pregnancy is a prospective Australian pre-birth cohort study of mothers consecutively recruited during their first obstetric clinic visit at Brisbane's Mater Hospital in 1981-1983. Participants completed the Pittsburgh Sleep Quality Index at the 21-year follow up. We linked this dataset to agency-recorded substantiated cases of childhood maltreatment. A series of separate logistic regression models was used to test whether childhood maltreatment predicted lower sleep quality after adjustment for selected confounders. Substantiated physical abuse significantly predicted lower sleep quality in males. Single and multiple forms of childhood maltreatment, including age of maltreatment and number of substantiations, did not predict lower sleep quality in either gender in both crude and adjusted models. Not being married, living in a residential problem area, cigarette smoking and internalising were significantly associated with lower sleep quality in a fully adjusted model for the male-female combined sample. Childhood maltreatment does not appear to predict young adult poor sleep quality, with the exception of physical abuse for males. While childhood maltreatment has been found to predict a range of mental health problems, childhood maltreatment does not appear to predict sleep problems occurring in young adults. Poor sleep quality was accounted for by concurrent social disadvantage, cigarette smoking and internalising. © 2017 Royal Australasian College of Physicians.
Optical data communication for Earth observation satellite systems
NASA Astrophysics Data System (ADS)
Fischer, J.; Loecherbach, E.
1991-10-01
The current development status of optical communication engineering in comparison to the conventional microwave systems and the different configurations of the optical data communication for Earth observation satellite systems are described. An outlook to future optical communication satellite systems is given. During the last decade Earth observation became more and more important for the extension of the knowledge about our planet and the human influence on nature. Today pictures taken by satellites are used, for example, to discover mineral resources or to predict harvest, crops, climate, and environment variations and their influence on the population. A new and up to date application for Earth observation satellites can be the verification of disarmament arrangements and the control of crises areas. To solve these tasks a system of Earth observing satellites with sensors tailored to the envisaged mission is necessary. Besides these low Earth orbiting satellites, a global Earth observation system consists of at least two data relay satellites. The communication between the satellites will be established via Inter-Satellite Links (ISL) and Inter-Orbit Links (IOL). On these links, bitrates up to 1 Gbit/s must be taken into account. Due to the increasing scarcity of suitable frequencies, higher carrier frequencies must probably be considered, and possible interference with terrestrial radio relay systems are two main problems for a realization in microwave technique. One important step to tackle these problems is the use of optical frequencies for IOL's and ISL's.
Nelson, Kristen C; Andow, David A; Banker, Michael J
2009-01-01
Societal evaluation of new technologies, specifically nanotechnology and genetically engineered organisms (GEOs), challenges current practices of governance and science. Employing environmental risk assessment (ERA) for governance and oversight assumes we have a reasonable ability to understand consequences and predict adverse effects. However, traditional ERA has come under considerable criticism for its many shortcomings and current governance institutions have demonstrated limitations in transparency, public input, and capacity. Problem Formulation and Options Assessment (PFOA) is a methodology founded on three key concepts in risk assessment (science-based consideration, deliberation, and multi-criteria analysis) and three in governance (participation, transparency, and accountability). Developed through a series of international workshops, the PFOA process emphasizes engagement with stakeholders in iterative stages, from identification of the problem(s) through comparison of multiple technology solutions that could be used in the future with their relative benefits, harms, and risk. It provides "upstream public engagement" in a deliberation informed by science that identifies values for improved decision making.
To trade or not to trade: Link prediction in the virtual water network
NASA Astrophysics Data System (ADS)
Tuninetti, Marta; Tamea, Stefania; Laio, Francesco; Ridolfi, Luca
2017-12-01
In the international trade network, links express the (temporary) presence of a commercial exchange of goods between any two countries. Given the dynamical behaviour of the trade network, where links are created and dismissed every year, predicting the link activation/deactivation is an open research question. Through the international trade network of agricultural goods, water resources are 'virtually' transferred from the country of production to the country of consumption. We propose a novel methodology for link prediction applied to the network of virtual water trade. Starting from the assumption of having links between any two countries, we estimate the associated virtual water flows by means of a gravity-law model using country and link characteristics as drivers. We consider the links with estimated flows higher than 1000 m3/year as active links, while the others as non-active links. Flows traded along estimated active links are then re-estimated using a similar but differently-calibrated gravity-law model. We were able to correctly model 84% of the existing links and 93% of the non-existing links in year 2011. It is worth to note that the predicted active links carry 99% of the global virtual water flow; hence, missed links are mainly those where a minimum volume of virtual water is exchanged. Results indicate that, over the period from 1986 to 2011, population, geographical distances between countries, and agricultural efficiency (through fertilizers use) are the major factors driving the link activation and deactivation. As opposed to other (network-based) models for link prediction, the proposed method is able to reconstruct the network architecture without any prior knowledge of the network topology, using only the nodes and links attributes; it thus represents a general method that can be applied to other networks such as food or value trade networks.
Asymmetric information in health insurance: evidence from the National Medical Expenditure Survey.
Cardon, J H; Hendel, I
2001-01-01
Adverse selection is perceived to be a major source of market failure in insurance markets. There is little empirical evidence on the extent of the problem. We estimate a structural model of health insurance and health care choices using data on single individuals from the NMES. A robust prediction of adverse-selection models is that riskier types buy more coverage and, on average, end up using more care. We test for unobservables linking health insurance status and health care consumption. We find no evidence of informational asymmetries.
Incorporating uncertainty in predictive species distribution modelling.
Beale, Colin M; Lennon, Jack J
2012-01-19
Motivated by the need to solve ecological problems (climate change, habitat fragmentation and biological invasions), there has been increasing interest in species distribution models (SDMs). Predictions from these models inform conservation policy, invasive species management and disease-control measures. However, predictions are subject to uncertainty, the degree and source of which is often unrecognized. Here, we review the SDM literature in the context of uncertainty, focusing on three main classes of SDM: niche-based models, demographic models and process-based models. We identify sources of uncertainty for each class and discuss how uncertainty can be minimized or included in the modelling process to give realistic measures of confidence around predictions. Because this has typically not been performed, we conclude that uncertainty in SDMs has often been underestimated and a false precision assigned to predictions of geographical distribution. We identify areas where development of new statistical tools will improve predictions from distribution models, notably the development of hierarchical models that link different types of distribution model and their attendant uncertainties across spatial scales. Finally, we discuss the need to develop more defensible methods for assessing predictive performance, quantifying model goodness-of-fit and for assessing the significance of model covariates.
An efficient link prediction index for complex military organization
NASA Astrophysics Data System (ADS)
Fan, Changjun; Liu, Zhong; Lu, Xin; Xiu, Baoxin; Chen, Qing
2017-03-01
Quality of information is crucial for decision-makers to judge the battlefield situations and design the best operation plans, however, real intelligence data are often incomplete and noisy, where missing links prediction methods and spurious links identification algorithms can be applied, if modeling the complex military organization as the complex network where nodes represent functional units and edges denote communication links. Traditional link prediction methods usually work well on homogeneous networks, but few for the heterogeneous ones. And the military network is a typical heterogeneous network, where there are different types of nodes and edges. In this paper, we proposed a combined link prediction index considering both the nodes' types effects and nodes' structural similarities, and demonstrated that it is remarkably superior to all the 25 existing similarity-based methods both in predicting missing links and identifying spurious links in a real military network data; we also investigated the algorithms' robustness under noisy environment, and found the mistaken information is more misleading than incomplete information in military areas, which is different from that in recommendation systems, and our method maintained the best performance under the condition of small noise. Since the real military network intelligence must be carefully checked at first due to its significance, and link prediction methods are just adopted to purify the network with the left latent noise, the method proposed here is applicable in real situations. In the end, as the FINC-E model, here used to describe the complex military organizations, is also suitable to many other social organizations, such as criminal networks, business organizations, etc., thus our method has its prospects in these areas for many tasks, like detecting the underground relationships between terrorists, predicting the potential business markets for decision-makers, and so on.
Wang, Zhe; Deater-Deckard, Kirby; Petrill, Stephen A; Thompson, Lee A
2012-08-01
Previous research documented a robust link between difficulties in self-regulation and development of externalizing problems (i.e., aggression and delinquency). In this study, we examined the longitudinal additive and interactive genetic and environmental covariation underlying this well-established link using a twin design. The sample included 131 pairs of monozygotic twins and 173 pairs of same-sex dizygotic twins who participated in three waves of annual assessment. Mothers and fathers provided reports of externalizing problems. Teacher report and observer rating were used to assess twin's attention regulation. The etiology underlying the link between externalizing problems and attention regulation shifted from a common genetic mechanism to a common environmental mechanism in the transition across middle childhood. Household chaos moderated the genetic variance of and covariance between externalizing problems and attention regulation. The genetic influence on individual differences in both externalizing problems and attention regulation was stronger in more chaotic households. However, higher levels of household chaos attenuated the genetic link between externalizing problems and attention regulation.
Wang, Zhe; Deater-Deckard, Kirby; Petrill, Stephen A.; Thompson, Lee A.
2015-01-01
Previous research has documented a robust link between difficulties in self-regulation and development of externalizing problems (i.e., aggression and delinquency). In the current study, we examined the longitudinal additive and interactive genetic and environmental covariation underlying this well-established link using a twin design. The sample included 131 pairs of monozygotic twins and 173 pairs of same-sex dizygotic twins who participated in three waves of annual assessment. Mothers and fathers provided reports of externalizing problems. Teacher report and observer rating were used to assess twin’s attention regulation. The etiology underlying the link between externalizing problems and attention regulation shifted from a common genetic mechanism to a common environmental mechanism in the transition across middle childhood. Household chaos moderated the genetic variance of and covariance between externalizing problems and attention regulation. The genetic influence on individual differences in both externalizing problems and attention regulation was stronger in more chaotic household. However, higher levels of household chaos attenuated the genetic link between externalizing problems and attention regulation. PMID:22781853
Obstacle avoidance handling and mixed integer predictive control for space robots
NASA Astrophysics Data System (ADS)
Zong, Lijun; Luo, Jianjun; Wang, Mingming; Yuan, Jianping
2018-04-01
This paper presents a novel obstacle avoidance constraint and a mixed integer predictive control (MIPC) method for space robots avoiding obstacles and satisfying physical limits during performing tasks. Firstly, a novel kind of obstacle avoidance constraint of space robots, which needs the assumption that the manipulator links and the obstacles can be represented by convex bodies, is proposed by limiting the relative velocity between two closest points which are on the manipulator and the obstacle, respectively. Furthermore, the logical variables are introduced into the obstacle avoidance constraint, which have realized the constraint form is automatically changed to satisfy different obstacle avoidance requirements in different distance intervals between the space robot and the obstacle. Afterwards, the obstacle avoidance constraint and other system physical limits, such as joint angle ranges, the amplitude boundaries of joint velocities and joint torques, are described as inequality constraints of a quadratic programming (QP) problem by using the model predictive control (MPC) method. To guarantee the feasibility of the obtained multi-constraint QP problem, the constraints are treated as soft constraints and assigned levels of priority based on the propositional logic theory, which can realize that the constraints with lower priorities are always firstly violated to recover the feasibility of the QP problem. Since the logical variables have been introduced, the optimization problem including obstacle avoidance and system physical limits as prioritized inequality constraints is termed as MIPC method of space robots, and its computational complexity as well as possible strategies for reducing calculation amount are analyzed. Simulations of the space robot unfolding its manipulator and tracking the end-effector's desired trajectories with the existence of obstacles and physical limits are presented to demonstrate the effectiveness of the proposed obstacle avoidance strategy and MIPC control method of space robots.
Evolutionary rescue: linking theory for conservation and medicine.
Alexander, Helen K; Martin, Guillaume; Martin, Oliver Y; Bonhoeffer, Sebastian
2014-12-01
Evolutionary responses that rescue populations from extinction when drastic environmental changes occur can be friend or foe. The field of conservation biology is concerned with the survival of species in deteriorating global habitats. In medicine, in contrast, infected patients are treated with chemotherapeutic interventions, but drug resistance can compromise eradication of pathogens. These contrasting biological systems and goals have created two quite separate research communities, despite addressing the same central question of whether populations will decline to extinction or be rescued through evolution. We argue that closer integration of the two fields, especially of theoretical understanding, would yield new insights and accelerate progress on these applied problems. Here, we overview and link mathematical modelling approaches in these fields, suggest specific areas with potential for fruitful exchange, and discuss common ideas and issues for empirical testing and prediction.
Spitznagel, M B; Jacobson, D M; Cox, M D; Carlson, M D
2018-06-01
Caregiver burden, found in many clients with a chronically or terminally ill companion animal, has been linked to poorer psychosocial function in the client and greater utilization of non-billable veterinary services. To reduce client caregiver burden, its determinants must first be identified. This study examined if companion animal clinical signs and problem behaviors predict veterinary client burden within broader client- and patient-based risk factor models. Data were collected in two phases. Phase 1 included 238 companion animal owners, including those with a sick companion animal (n=119) and matched healthy controls (n=119) recruited online. Phase 2 was comprised of 602 small animal general veterinary hospital clients (n=95 with a sick dog or cat). Participants completed cross-sectional online assessments of caregiver burden, psychosocial resources (social support, active coping, self-mastery), and an item pool of companion animal clinical signs and problem behaviors. Several signs/behaviors correlated with burden, most prominently: weakness, appearing sad/depressed or anxious, appearing to have pain/discomfort, change in personality, frequent urination, and excessive sleeping/lethargy. Within patient-based risk factors, caregiver burden was predicted by frequency of the companion animal's signs/behaviors (P<.01). Within client-based factors, potentially modifiable factors of client reaction to the animal's signs/behaviors (P=.01), and client sense of control (P<.04) predicted burden. Understanding burden may enhance veterinarian-client communication, and is important due to potential downstream effects of client burden, such as higher workload for the veterinarian. Supporting the client's sense of control may help alleviate burden when amelioration of the companion animal's presentation is not feasible. Copyright © 2018 Elsevier Ltd. All rights reserved.
Modeling flow, sediment transport and morphodynamics in rivers
Nelson, Jonathan M.; McDonald, Richard R.; Shimizu, Yasuyuki; Kimura, Ichiro; Nabi, Mohamed; Asahi, Kazutake
2016-01-01
Predicting the response of natural or man-made channels to imposed supplies of water and sediment is one of the difficult practical problems commonly addressed by fluvial geomorphologists. This problem typically arises in three situations. In the first situation, geomorphologists are attempting to understand why a channel or class of channels has a certain general form; in a sense, this is the central goal of fluvial geomorphology. In the second situation, geomorphologists are trying to understand and explain how and why a specific channel will evolve or has evolved in response to altered or unusual sediment and water supplies to that channel. For example, this would include explaining the short-term response of a channel to an unusually large flood or predicting the response of a channel to long-term changes in flow or sediment supply due to various human activities such as damming or diversions. Finally, geomorphologists may be called upon to design or assess the design of proposed man-made channels that must carry a certain range of flows and sediment loads in a stable or at least quasi-stable manner. In each of these three situations, the problem is really the same: geomorphologists must understand and predict the interaction of the flow field in the channel, the sediment movement in the channel and the geometry of the channel bed and banks. In general, the flow field, the movement of sediment making up the bed and the morphology of the bed are intricately linked; the flow moves the sediment, the bed is altered by erosion and deposition of sediment and the shape of the bed is critically important for predicting the flow. This complex linkage is precisely what makes understanding channel form and process such a difficult and interesting challenge.
Wright, Adam; Laxmisan, Archana; Ottosen, Madelene J; McCoy, Jacob A; Butten, David; Sittig, Dean F
2012-01-01
Objective We describe a novel, crowdsourcing method for generating a knowledge base of problem–medication pairs that takes advantage of manually asserted links between medications and problems. Methods Through iterative review, we developed metrics to estimate the appropriateness of manually entered problem–medication links for inclusion in a knowledge base that can be used to infer previously unasserted links between problems and medications. Results Clinicians manually linked 231 223 medications (55.30% of prescribed medications) to problems within the electronic health record, generating 41 203 distinct problem–medication pairs, although not all were accurate. We developed methods to evaluate the accuracy of the pairs, and after limiting the pairs to those meeting an estimated 95% appropriateness threshold, 11 166 pairs remained. The pairs in the knowledge base accounted for 183 127 total links asserted (76.47% of all links). Retrospective application of the knowledge base linked 68 316 medications not previously linked by a clinician to an indicated problem (36.53% of unlinked medications). Expert review of the combined knowledge base, including inferred and manually linked problem–medication pairs, found a sensitivity of 65.8% and a specificity of 97.9%. Conclusion Crowdsourcing is an effective, inexpensive method for generating a knowledge base of problem–medication pairs that is automatically mapped to local terminologies, up-to-date, and reflective of local prescribing practices and trends. PMID:22582202
A link prediction method for heterogeneous networks based on BP neural network
NASA Astrophysics Data System (ADS)
Li, Ji-chao; Zhao, Dan-ling; Ge, Bing-Feng; Yang, Ke-Wei; Chen, Ying-Wu
2018-04-01
Most real-world systems, composed of different types of objects connected via many interconnections, can be abstracted as various complex heterogeneous networks. Link prediction for heterogeneous networks is of great significance for mining missing links and reconfiguring networks according to observed information, with considerable applications in, for example, friend and location recommendations and disease-gene candidate detection. In this paper, we put forward a novel integrated framework, called MPBP (Meta-Path feature-based BP neural network model), to predict multiple types of links for heterogeneous networks. More specifically, the concept of meta-path is introduced, followed by the extraction of meta-path features for heterogeneous networks. Next, based on the extracted meta-path features, a supervised link prediction model is built with a three-layer BP neural network. Then, the solution algorithm of the proposed link prediction model is put forward to obtain predicted results by iteratively training the network. Last, numerical experiments on the dataset of examples of a gene-disease network and a combat network are conducted to verify the effectiveness and feasibility of the proposed MPBP. It shows that the MPBP with very good performance is superior to the baseline methods.
MacKay, Sherri; Henderson, Joanna; Del Bove, Giannetta; Marton, Peter; Warling, Diane; Root, Carol
2006-09-01
In the DSM-IV-TR, firesetting is included as a criterion for the diagnoses of conduct disorder and pyromania. The link between firesetting and antisocial behavior is well established in the empirical literature. Although theoretical models of firesetting often include fire interest as a putative risk factor, there is little research on the role of fire interest in firesetting or on the construct of pyromania. The present study evaluated a sample of children and adolescents referred to an outpatient specialty program for juvenile firesetters with firesetting as the primary presenting problem. By assessing fire interest and antisocial behavior concurrently, the contribution of fire interest to firesetting after controlling for the role of conduct problems was evaluated. Results revealed that fire interest and antisocial behavior were significantly and positively correlated. Moreover, variations in fire interest added to the prediction of firesetting severity at assessment and firesetting recidivism at 18-month follow-up above and beyond what was predicted by antisociality alone. These findings have implications for an empirically derived taxonomy of pathological firesetting.
Kuss, Daria J; Louws, Jorik; Wiers, Reinout W
2012-09-01
Recently, there have been growing concerns about excessive online gaming. Playing Massively Multiplayer Online Role-Playing Games (MMORPGs) appears to be particularly problematic, because these games require a high degree of commitment and time investment from the players to the detriment of occupational, social, and other recreational activities and relations. A number of gaming motives have been linked to excessive online gaming in adolescents and young adults. We assessed 175 current MMORPG players and 90 nonplayers using a Web-based questionnaire regarding their gaming behavior, problems as consequences of gaming, and game motivations and tested their statistical associations. Results indicated that (a) MMORPG players are significantly more likely to experience gaming-related problems relative to nonplayers, and that (b) the gaming motivations escapism and mechanics significantly predicted excessive gaming and appeared as stronger predictors than time investment in game. The findings support the necessity of using measures that distinguish between different types of online games. In addition, this study proves useful regarding the current discussion on establishing (online) gaming addiction as a diagnosis in future categorizations of psychopathology.
Davies, Patrick T; Martin, Meredith J; Sturge-Apple, Melissa L; Ripple, Michael T; Cicchetti, Dante
2016-10-01
Two studies tested hypotheses about the distinctive psychological consequences of children's patterns of responding to interparental conflict. In Study 1, 174 preschool children (M = 4.0 years) and their mothers participated in a cross-sectional design. In Study 2, 243 preschool children (M = 4.6 years) and their parents participated in 2 annual measurement occasions. Across both studies, multiple informants assessed children's psychological functioning. Guided by the reformulated version of emotional security theory, behavioral observations of children's coping with interparental conflict assessed their tendencies to exhibit 4 patterns based on their function in defusing threat: secure (i.e., efficiently address direct instances of threat), mobilizing (i.e., react to potential threat and social opportunities), dominant (i.e., directly defeat threat), and demobilizing (i.e., reduce salience as a target of hostility). As hypothesized, each profile predicted unique patterns of adjustment. Greater security was associated with lower levels of internalizing and externalizing symptoms and greater social competence, whereas higher dominance was associated with externalizing problems and extraversion. In contrast, mobilizing patterns of reactivity predicted more problems with self-regulation, internalizing symptoms, externalizing difficulties, but also greater extraversion. Finally, higher levels of demobilizing reactivity were linked with greater internalizing problems and lower extraversion but also better self-regulation. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Boldt, Lea J.; Kochanska, Grazyna; Yoon, Jeung Eun; Nordling, Jamie Koenig
2014-01-01
We examined children’s attachment security with their mothers and fathers in a community sample (N = 100). At 25 months, mothers, fathers, and trained observers completed Attachment Q-Set (AQS). At 100 months, children completed Kerns Security Scale (KSS) for each parent. Children’s adaptation (behavior problems and competence in broader ecologies of school and peer group, child- and parent-reported) was assessed at 100 months. By and large, the child’s security with the mother and father was modestly to robustly concordant across both relationships, depending on the assessment method. Observers’ AQS security scores predicted children’s self-reported security 6 years later. For children with low AQS security scores with mothers, variations in security with fathers had significant implications for adaptation: Those whose security with fathers was also low reported the most behavior problems and were seen as least competent in broader ecologies, but those whose security with fathers was high reported few problems and were seen as competent. Security with fathers, observer-rated and child-reported, predicted children’s higher competence in broader ecologies. A cumulative index of the history of security from toddler age to middle childhood, integrating measures across both relationships and diverse methodologies, was significantly associated with positive adaptation at 100 months. PMID:24605850
Davies, Patrick T.; Martin, Meredith J.; Sturge-Apple, Melissa L.; Ripple, Michael T.; Cicchetti, Dante
2016-01-01
Two studies tested hypotheses about the distinctive psychological consequences of children’s patterns of responding to interparental conflict. In Study 1, 174 preschool children (M = 4.0 years) and their mothers participated in a cross-sectional design. In Study 2, 243 preschool children (M = 4.6 years) and their parents participated in two annual measurement occasions. Across both studies, multiple informants assessed children’s psychological functioning. Guided by the reformulated version of emotional security theory, behavioral observations of children’s coping with interparental conflict assessed their tendencies to exhibit four patterns based on their function in defusing threat: secure (i.e., efficiently address direct instances of threat), mobilizing (i.e., react to potential threat and social opportunities), dominant (i.e., directly defeat threat), and demobilizing (i.e., reduce salience as a target of hostility). As hypothesized, each profile predicted unique patterns of adjustment. Greater security was associated with lower levels of internalizing and externalizing symptoms and greater social competence, whereas higher dominance was associated with externalizing problems and extraversion. In contrast, mobilizing patterns of reactivity predicted more problems with self-regulation, internalizing symptoms, externalizing difficulties, but also greater extraversion. Finally, higher levels of demobilizing reactivity were linked with greater internalizing problems and lower extraversion but also better self-regulation. PMID:27598256
Cognitive grammar and aphasic discourse.
Manning, Molly; Franklin, Sue
2016-01-01
In cognitive grammar (CG), there is no clear division between language and other cognitive processes; all linguistic form is conceptually meaningful. In this pilot study, a CG approach was applied to investigate whether people with aphasia (PWA) have cognitive linguistic difficulty not predicted from traditional, componential models of aphasia. Narrative samples from 22 PWA (6 fluent, 16 non-fluent) were compared with samples from 10 participants without aphasia. Between-group differences were tested statistically. PWA had significant difficulty with temporal sequencing, suggesting problems that are not uniquely linguistic. For some, these problems were doubly dissociated with naming, used as a general measure of severity, which indicates that cognitive linguistic difficulties are not linked with more widespread brain damage. Further investigation may lead to a richer account of aphasia in line with contemporary linguistics and cognitive science approaches.
Grych, John H; Harold, Gordon T; Miles, Claire J
2003-01-01
This longitudinal study tested the role of children's appraisals of threat and self-blame as mediators of the association between interparental conflict and child adjustment in a sample of 298 Welsh children ages 11 to 12 years. Exposure to higher levels of interparental conflict at Time 1 predicted greater perceived threat and self-blame at Time 2, after accounting for the effects of Time 1 adjustment and appraisals on later appraisals. Perceived threat in turn was associated with increased internalizing problems at Tune 2, and self-blame was associated with higher externalizing problems. The pattern of results was largely consistent for child and parent reports of conflict and for boys and girls, though some gender differences were found in associations between appraisals and adjustment.
NASA Technical Reports Server (NTRS)
Schubert, Siegfried; Dole, Randall; vandenDool, Huug; Suarez, Max; Waliser, Duane
2002-01-01
This workshop, held in April 2002, brought together various Earth Sciences experts to focus on the subseasonal prediction problem. While substantial advances have occurred over the last few decades in both weather and seasonal prediction, progress in improving predictions on these intermediate time scales (time scales ranging from about two weeks to two months) has been slow. The goals of the workshop were to get an assessment of the "state of the art" in predictive skill on these time scales, to determine the potential sources of "untapped" predictive skill, and to make recommendations for a course of action that will accelerate progress in this area. One of the key conclusions of the workshop was that there is compelling evidence for predictability at forecast lead times substantially longer than two weeks. Tropical diabatic heating and soil wetness were singled out as particularly important processes affecting predictability on these time scales. Predictability was also linked to various low-frequency atmospheric "phenomena" such as the annular modes in high latitudes (including their connections to the stratosphere), the Pacific/North American (PNA) pattern, and the Madden Julian Oscillation (MJO). The latter, in particular, was highlighted as a key source of untapped predictability in the tropics and subtropics, including the Asian and Australian monsoon regions.
ERIC Educational Resources Information Center
Lansford, Jennifer E.; Erath, Stephen; Yu, Tianyi; Pettit, Gregory S.; Dodge, Kenneth A.; Bates, John E.
2008-01-01
Background: Previous theory and research suggest links between substance use and externalizing behavior problems, but links between substance use and internalizing problems are less clear. The present study sought to understand concurrent links among diagnoses of substance use disorders, internalizing disorders, and behavior disorders at age 18 as…
Scrimgeour, Meghan B.; Davis, Elizabeth L.; Buss, Kristin A.
2015-01-01
Prosocial behavior in early childhood is a precursor to later adaptive social functioning. This investigation leveraged mother-reported, physiological, and observational data to examine children’s prosocial development from age 2 to age 4 (N = 125). Maternal emotion socialization (ES) strategies and children’s parasympathetic regulation have each been implicated in prosocial behavior, but are rarely examined together or prospectively. Given the transactional nature of parent-child relationships, the effects of maternal ES strategies on children’s prosocial behavior are likely moderated by children’s individual differences in parasympathetic regulation. As predicted, mothers’ reported use of problem-focused ES strategies predicted prosocial behavior at age 4. Additionally, children who showed parasympathetic reactivity consistent with more effective emotion regulation during a lab-based disappointment task were rated as more prosocial at age 4. Several interactions with maternal ES strategies emerged. Children’s parasympathetic regulation moderated the relations between observed physical comfort or cognitive reframing and prosocial behavior. Observed distraction (either behavioral or cognitive) moderated the link between mothers’ reported use of problem-focused ES strategies and children’s prosocial behavior. Findings suggest that children’s emerging prosocial behavior is shaped by the interactive contributions of inter-personal maternal ES as well as intra-personal intrinsic physiological regulation. PMID:26569566
Heberle, Amy E; Krill, Sarah C; Briggs-Gowan, Margaret J; Carter, Alice S
2015-01-01
This study tested an ecological model predicting children's behavior problems in kindergarten from risk and protective factors (parent psychological distress, parenting behavior, and social support) during early childhood. Study participants were 1,161 sociodemographically diverse mother-child pairs that participated in a longitudinal birth cohort study. The predictor variables were collected at two separate time points and based on parent reports; children were an average of 2 years old at Time 1 and 3 years old at Time 2. The outcome measures were collected when children reached kindergarten and were 6 years old on average. Our results show that early maternal psychological distress, mediated by suboptimal parenting behavior, predicts children's externalizing and internalizing behaviors in kindergarten. Moreover, early social support buffers the relations between psychological distress and later suboptimal parenting behavior and between suboptimal parenting behavior and later depressive/withdrawn behavior. Our findings have several implications for early intervention and prevention efforts. Of note, informal social support appears to play an important protective role in the development of externalizing and internalizing behavior problems, weakening the link between psychological distress and less optimal parenting behavior and between suboptimal parenting behavior and children's withdrawal/depression symptoms. Increasing social support may be a productive goal for family and community-level intervention.
Internet traffic load balancing using dynamic hashing with flow volume
NASA Astrophysics Data System (ADS)
Jo, Ju-Yeon; Kim, Yoohwan; Chao, H. Jonathan; Merat, Francis L.
2002-07-01
Sending IP packets over multiple parallel links is in extensive use in today's Internet and its use is growing due to its scalability, reliability and cost-effectiveness. To maximize the efficiency of parallel links, load balancing is necessary among the links, but it may cause the problem of packet reordering. Since packet reordering impairs TCP performance, it is important to reduce the amount of reordering. Hashing offers a simple solution to keep the packet order by sending a flow over a unique link, but static hashing does not guarantee an even distribution of the traffic amount among the links, which could lead to packet loss under heavy load. Dynamic hashing offers some degree of load balancing but suffers from load fluctuations and excessive packet reordering. To overcome these shortcomings, we have enhanced the dynamic hashing algorithm to utilize the flow volume information in order to reassign only the appropriate flows. This new method, called dynamic hashing with flow volume (DHFV), eliminates unnecessary flow reassignments of small flows and achieves load balancing very quickly without load fluctuation by accurately predicting the amount of transferred load between the links. In this paper we provide the general framework of DHFV and address the challenges in implementing DHFV. We then introduce two algorithms of DHFV with different flow selection strategies and show their performances through simulation.
One-Year Prospective Study on Passion and Gambling Problems in Poker Players.
Morvannou, Adèle; Dufour, Magali; Brunelle, Natacha; Berbiche, Djamal; Roy, Élise
2018-06-01
The concept of passion is relevant to understanding gambling behaviours and gambling problems. Longitudinal studies are useful to better understand the absence and development of gambling problems; however, only one study has specifically considered poker players. Using a longitudinal design, this study aims to determine the influence, 1 year later, of two forms of passion-harmonious and obsessive-on gambling problems in poker players. A total of 116 poker players was recruited from across Quebec, Canada. The outcome variable of interest was participants' category on the Canadian Pathological Gambling Index, and the predictive variable was the Gambling Passion Scale. Multiple logistic regression analyses were conducted to identify independent risk factors of at-risk poker players 1 year later. Obsessive passion at baseline doubled the risk of gambling problems 1 year later (p < 0.01); for harmonious passion, there was no association. Number of gambling activities, drug problems, and impulsivity were also associated with at-risk gambling. This study highlights the links between obsessive passion and at-risk behaviours among poker players. It is therefore important to prevent the development of obsessive passion among poker players.
Dixon-Gordon, Katherine L; Whalen, Diana J; Scott, Lori N; Cummins, Nicole D; Stepp, Stephanie D
2016-06-01
The transaction of adolescent's expressed negative affect and parental interpersonal emotion regulation are theoretically implicated in the development of borderline personality disorder (BPD). Although problem solving and support/validation are interpersonal strategies that foster emotion regulation, little is known about whether these strategies are associated with less BPD severity among adolescents. Adolescent girls (age 16; N = 74) and their mothers completed a conflict discussion task, and maternal problem solving, support/validation, and girls' negative affect were coded. Girls' BPD symptoms were assessed at four time points. A 3-way interaction of girls' negative affect, problem solving, and support/validation indicated that girls' negative affect was only associated with BPD severity in the context of low maternal support/validation and high maternal problem solving. These variables did not predict changes in BPD symptoms over time. Although high negative affect is a risk for BPD severity in adolescent girls, maternal interpersonal emotion regulation strategies moderate this link. Whereas maternal problem solving coupled with low support/validation is associated with a stronger negative affect-BPD relation, maternal problem solving paired with high support/validation is associated with an attenuated relationship.
Whalen, Diana J.; Scott, Lori N.; Cummins, Nicole D.; Stepp, Stephanie D.
2015-01-01
The transaction of adolescent’s expressed negative affect and parental interpersonal emotion regulation are theoretically implicated in the development of borderline personality disorder (BPD). Although problem solving and support/validation are interpersonal strategies that foster emotion regulation, little is known about whether these strategies are associated with less BPD severity among adolescents. Adolescent girls (age 16; N = 74) and their mothers completed a conflict discussion task, and maternal problem solving, support/validation, and girls’ negative affect were coded. Girls’ BPD symptoms were assessed at four time points. A 3-way interaction of girls’ negative affect, problem solving, and support/validation indicated that girls’ negative affect was only associated with BPD severity in the context of low maternal support/validation and high maternal problem solving. These variables did not predict changes in BPD symptoms over time. Although high negative affect is a risk for BPD severity in adolescent girls, maternal interpersonal emotion regulation strategies moderate this link. Whereas maternal problem solving coupled with low support/validation is associated with a stronger negative affect-BPD relation, maternal problem solving paired with high support/validation is associated with an attenuated relationship. PMID:27185969
Links between motor control and classroom behaviors: Moderation by low birth weight
Razza, Rachel A.; Martin, Anne; Brooks-Gunn, Jeanne
2016-01-01
It is unclear from past research on effortful control whether one of its components, motor control, independently contributes to adaptive classroom behaviors. The goal of this study was to identify associations between early motor control, measured by the walk-a-line task at age 3, and teacher-reported learning-related behaviors (approaches to learning and attention problems) and behavior problems in kindergarten classrooms. Models tested whether children who were vulnerable to poorer learning behaviors and more behavior problems due to having been born low birth weight benefited more, less, or the same as other children from better motor control. Data were drawn from the national Fragile Families and Child-Wellbeing Study (n = 751). Regression models indicated that motor control was significantly associated with better approaches to learning and fewer behavior problems. Children who were low birth weight benefitted more than normal birth weight children from better motor control with respect to their approaches to learning, but equally with respect to behavior problems. Additionally, for low but not normal birth weight children, better motor control predicted fewer attention problems. These findings suggest that motor control follows a compensatory model of development for low birth weight children and classroom behaviors. PMID:27594776
Madigan, Sheri; Wade, Mark; Plamondon, Andre; Jenkins, Jennifer
2015-01-01
The current study examined a temporal cascade linking mothers' history of abuse with their children's internalizing difficulties through proximal processes such as maternal postnatal depressive symptoms and responsive parenting. Participants consisted of 490 mother-child dyads assessed at three time points when children were, on average, 2 months old at Time 1 (T1), 18 months at Time 2 (T2), and 36 months at Time 3 (T3). Maternal abuse history and depressive symptoms were assessed via questionnaires at T1. Observations of responsive parenting were collected at T2 and were coded using a validated coding scheme. Children's internalizing difficulties were assessed in the preschool period using averaged parental reports. Path analysis revealed that maternal physical abuse was associated with depressive symptoms postnatally, which were in turn associated with children's internalizing behavior at 36 months of age. We also found that the association between physical abuse history and responsive parenting operated indirectly through maternal depressive symptoms. These findings remained after controlling for covariates including socioeconomic status, child gender, and age. After accounting for physical abuse history, sexual abuse history was not associated with child internalizing problems either directly or indirectly through maternal depressive symptoms and/or parenting behavior. Thus, mothers' physical abuse history is a risk factor for relatively poor mental health, which is itself predictive of both later parenting behavior and children's internalizing problems. © 2015 Michigan Association for Infant Mental Health.
Goeke-Morey, Marcie C; Taylor, Laura K; Merrilees, Christine E; Shirlow, Peter; Cummings, E Mark
2014-12-01
A growing literature supports the importance of understanding the link between religiosity and youths' adjustment and development, but in the absence of rigorous, longitudinal designs, questions remain about the direction of effect and the role of family factors. This paper investigates the bidirectional association between adolescents' relationship with God and their internalizing adjustment. Results from 2-wave, SEM cross-lag analyses of data from 667 mother/adolescent dyads in Belfast, Northern Ireland (50% male, M age = 15.75 years old) supports a risk model suggesting that greater internalizing problems predict a weaker relationship with God 1 year later. Significant moderation analyses suggest that a stronger relationship with God predicted fewer depression and anxiety symptoms for youth whose mothers used more religious coping.
Neuroticism and Extraversion in Youth Predict Mental Wellbeing and Life Satisfaction 40 Years Later
Gale, Catharine R; Booth, Tom; Mõttus, René; Kuh, Diana; Deary, Ian J
2014-01-01
Neuroticism and Extraversion are linked with current wellbeing, but it is unclear whether these traits in youth predict wellbeing decades later. We applied structural equation modelling to data from 4583 people from the MRC National Survey of Health and Development. We examined the effects of Neuroticism and Extraversion at ages 16 and 26 years on mental wellbeing and life satisfaction at age 60-64 and explored the mediating roles of psychological and physical health. Extraversion had direct, positive effects on both measures of wellbeing. The impact of Neuroticism on both wellbeing and life satisfaction was largely indirect through susceptibility to psychological distress and physical health problems. Personality dispositions in youth have enduring influence on wellbeing assessed about forty years later. PMID:24563560
Goeke-Morey, Marcie C.; Taylor, Laura K.; Merrilees, Christine E.; Shirlow, Peter; Cummings, E. Mark
2015-01-01
A growing literature supports the importance of understanding the link between religiosity and youths’ adjustment and development, but in the absence of rigorous, longitudinal designs, questions remain about the direction of effect and the role of family factors. This paper investigates the bi-directional association between adolescents’ relationship with God and their internalizing adjustment. Results from two-wave, SEM cross-lag analyses of data from 667 mother/adolescent dyads in Belfast, Northern Ireland (50% male, M age = 15.75 years old) supports a risk model suggesting that greater internalizing problems predicts a weaker relationship with God one year later. Significant moderation analyses suggest that a stronger relationship with God predicted fewer depression and anxiety symptoms for youth whose mothers used more religious coping. PMID:24955590
Henriksen, Ingvild Oxås; Ranøyen, Ingunn; Indredavik, Marit Sæbø; Stenseng, Frode
2017-01-01
Self-esteem is fundamentally linked to mental health, but its' role in trajectories of psychiatric problems is unclear. In particular, few studies have addressed the role of self-esteem in the development of attention problems. Hence, we examined the role of global self-esteem in the development of symptoms of anxiety/depression and attention problems, simultaneously, in a clinical sample of adolescents while accounting for gender, therapy, and medication. Longitudinal data were obtained from a sample of 201 adolescents-aged 13-18-referred to the Department of Child and Adolescent Psychiatry in Trondheim, Norway. In the baseline study, self-esteem, and symptoms of anxiety/depression and attention problems were measured by means of self-report. Participants were reassessed 3 years later, with a participation rate of 77% in the clinical sample. Analyses showed that high self-esteem at baseline predicted fewer symptoms of both anxiety/depression and attention problems 3 years later after controlling for prior symptom levels, gender, therapy (or not), and medication. Results highlight the relevance of global self-esteem in the clinical practice, not only with regard to emotional problems, but also to attention problems. Implications for clinicians, parents, and others are discussed.
Link Prediction in Evolving Networks Based on Popularity of Nodes.
Wang, Tong; He, Xing-Sheng; Zhou, Ming-Yang; Fu, Zhong-Qian
2017-08-02
Link prediction aims to uncover the underlying relationship behind networks, which could be utilized to predict missing edges or identify the spurious edges. The key issue of link prediction is to estimate the likelihood of potential links in networks. Most classical static-structure based methods ignore the temporal aspects of networks, limited by the time-varying features, such approaches perform poorly in evolving networks. In this paper, we propose a hypothesis that the ability of each node to attract links depends not only on its structural importance, but also on its current popularity (activeness), since active nodes have much more probability to attract future links. Then a novel approach named popularity based structural perturbation method (PBSPM) and its fast algorithm are proposed to characterize the likelihood of an edge from both existing connectivity structure and current popularity of its two endpoints. Experiments on six evolving networks show that the proposed methods outperform state-of-the-art methods in accuracy and robustness. Besides, visual results and statistical analysis reveal that the proposed methods are inclined to predict future edges between active nodes, rather than edges between inactive nodes.
Patock-Peckham, Julie A; King, Kevin M; Morgan-Lopez, Antonio A; Ulloa, Emilio C; Moses, Jennifer M Filson
2011-03-01
Recently, it has been suggested that traits may dynamically change as conditions change. One possible mechanism that may influence impulsiveness is parental monitoring. Parental monitoring reflects a knowledge regarding one's offspring's whereabouts and social connections. The aim of this investigation was to examine potential gender-specific parental influences to impulsiveness (general behavioral control), control over one's own drinking (specific behavioral control), and alcohol-related problems among individuals in a period of emerging adulthood. Direct and mediational links between parenting styles (permissive, authoritarian, and authoritative), parental monitoring, impulsiveness, drinking control, and alcohol-related problems were investigated. A multiple-group, SEM model with (316 women, 265 men) university students was examined. In general, the overall pattern among male and female respondents was distinct. For daughters, perceptions of a permissive father were indirectly linked to more alcohol-related problems through lower levels of monitoring by fathers and more impulsive symptoms. Perceptions of an authoritative father were also indirectly linked to fewer impulsive symptoms through higher levels of monitoring by fathers among daughters. For men, perceptions of a permissive mother were indirectly linked to more alcohol-related problems through lower levels of monitoring by mothers and more impulsive symptoms. For sons, perceptions of mother authoritativeness were indirectly linked to fewer alcohol-related problems through more monitoring by mothers and fewer impulsive symptoms. Monitoring by an opposite-gender parent mediated the link between parenting styles (i.e., permissive, authoritative) on impulsiveness.
Negative Relational Schemas Predict the Trajectory of Coercive Dynamics During Early Childhood
Smith, Justin D.; Dishion, Thomas J.; Shaw, Daniel S.; Wilson, Melvin N.
2014-01-01
Coercive family processes are germane to the development of problem behaviors in early childhood, yet the cognitive and affective underpinnings are not well understood. We hypothesized that one antecedent of early coercive interactions is the caregiver’s implicit affective attitudes toward the child, which in this article are termed relational schemas. Relational schemas have previously been linked to coercion and problem behaviors, but there has yet to be an examination of the association between relational schemas and trajectories of coercion during early childhood. We examined 731 indigent caregiver-child dyads (49% female children) from a randomized intervention trial of the Family Check-Up. Predominantly biological mothers participated. A speech sample was used to assess relational schemas at age 2. Coercive interactions were assessed observationally each year between ages 2 and 4. Caregiver and teacher reports of children’s oppositional and aggressive behaviors were collected at age 7.5 and 8.5. Path analysis revealed that negative relational schemas were associated with less steep declines in coercion during this period, which in turn were predictive of ratings of oppositional and aggressive behaviors at age 7.5/8.5 after controlling for baseline levels, positive relational schemas, child gender, ethnicity, and cumulative risk. Intervention condition assignment did not moderate this relationship, suggesting the results represent a naturally occurring process. Given the link between persistent early coercion and later deleterious outcomes, relational schemas that maintain and amplify coercive dynamics represent a potential target for early intervention programs designed to improve parent–child relationships. PMID:25208813
A group evolving-based framework with perturbations for link prediction
NASA Astrophysics Data System (ADS)
Si, Cuiqi; Jiao, Licheng; Wu, Jianshe; Zhao, Jin
2017-06-01
Link prediction is a ubiquitous application in many fields which uses partially observed information to predict absence or presence of links between node pairs. The group evolving study provides reasonable explanations on the behaviors of nodes, relations between nodes and community formation in a network. Possible events in group evolution include continuing, growing, splitting, forming and so on. The changes discovered in networks are to some extent the result of these events. In this work, we present a group evolving-based characterization of node's behavioral patterns, and via which we can estimate the probability they tend to interact. In general, the primary aim of this paper is to offer a minimal toy model to detect missing links based on evolution of groups and give a simpler explanation on the rationality of the model. We first introduce perturbations into networks to obtain stable cluster structures, and the stable clusters determine the stability of each node. Then fluctuations, another node behavior, are assumed by the participation of each node to its own belonging group. Finally, we demonstrate that such characteristics allow us to predict link existence and propose a model for link prediction which outperforms many classical methods with a decreasing computational time in large scales. Encouraging experimental results obtained on real networks show that our approach can effectively predict missing links in network, and even when nearly 40% of the edges are missing, it also retains stationary performance.
Lansford, Jennifer E.; Criss, Michael M.; Pettit, Gregory S.; Dodge, Kenneth A.; Bates, John E.
2009-01-01
Quality of peer relationships and perceived peer antisocial behavior were examined as moderators of the link between negative parenting and externalizing behavior problems in school from middle childhood to early adolescence. Data on negative parenting (i.e., unilateral parental decision making, low supervision and awareness, and harsh discipline) were collected from 362 parents in the summer preceding the adolescents’ entry into Grade 6. Adolescent reports of positive peer relationships and peer antisocial behavior were assessed in the winter of Grade 7. The outcome measure was teacher report of adolescent externalizing behavior in the spring of Grade 7, controlling for externalizing behavior in Grade 5. High levels of friendship quality and peer group affiliation attenuated the association between unilateral parental decision making and adolescent externalizing behavior in school; this was particularly true when adolescents associated with peers perceived to be low in antisocial behavior. In addition, having low-quality peer relationships and having peers perceived to be highly antisocial further amplified the association between unilateral parental decision making and adolescent externalizing behavior problems. Finally, high levels of friend and peer group antisocial behavior exacerbated the predictiveness of harsh discipline for adolescents’ externalizing behavior. PMID:20209019
Structural equation modeling of pesticide poisoning, depression, safety, and injury.
Beseler, Cheryl L; Stallones, Lorann
2013-01-01
The role of pesticide poisoning in risk of injuries may operate through a link between pesticide-induced depressive symptoms and reduced engagement in safety behaviors. The authors conducted structural equation modeling of cross-sectional data to examine the pattern of associations between pesticide poisoning, depressive symptoms, safety knowledge, safety behaviors, and injury. Interviews of 1637 Colorado farm operators and their spouses from 964 farms were conducted during 1993-1997. Pesticide poisoning was assessed based on a history of ever having been poisoned. The Center for Epidemiologic Studies-Depression scale was used to assess depressive symptoms. Safety knowledge and safety behaviors were assessed using ten items for each latent variable. Outcomes were safety behaviors and injuries. A total of 154 injuries occurred among 1604 individuals with complete data. Pesticide poisoning, financial problems, health, and age predicted negative affect/somatic depressive symptoms with similar effect sizes; sex did not. Depression was more strongly associated with safety behavior than was safety knowledge. Two safety behaviors were significantly associated with an increased risk of injury. This study emphasizes the importance of financial problems and health on depression, and provides further evidence for the link between neurological effects of past pesticide poisoning on risk-taking behaviors and injury.
Tug of war of molecular motors: the effects of uneven load sharing
NASA Astrophysics Data System (ADS)
Bouzat, Sebastián; Falo, Fernando
2011-12-01
We analyze theoretically the problem of cargo transport along microtubules by motors of two species with opposite polarities. We consider two different one-dimensional models previously developed in the literature: a quite widespread model which assumes equal force sharing, here referred to as the mean field model (MFM), and a stochastic model (SM) which considers individual motor-cargo links. We find that in generic situations, the MFM predicts larger cargo mean velocity, smaller mean run time and less frequent reversions than the SM. These phenomena are found to be the consequences of the load sharing assumptions and can be interpreted in terms of the probabilities of the different motility states. We also explore the influence of the viscosity in both models and the role of the stiffness of the motor-cargo links within the SM. Our results show that the mean cargo velocity is independent of the stiffness, while the mean run time decreases with such a parameter. We explore the case of symmetric forward and backward motors considering kinesin-1 parameters, and the problem of transport by kinesin-1 and cytoplasmic dyneins considering two different sets of parameters previously proposed for dyneins.
Predicting optimum crop designs using crop models and seasonal climate forecasts.
Rodriguez, D; de Voil, P; Hudson, D; Brown, J N; Hayman, P; Marrou, H; Meinke, H
2018-02-02
Expected increases in food demand and the need to limit the incorporation of new lands into agriculture to curtail emissions, highlight the urgency to bridge productivity gaps, increase farmers profits and manage risks in dryland cropping. A way to bridge those gaps is to identify optimum combination of genetics (G), and agronomic managements (M) i.e. crop designs (GxM), for the prevailing and expected growing environment (E). Our understanding of crop stress physiology indicates that in hindsight, those optimum crop designs should be known, while the main problem is to predict relevant attributes of the E, at the time of sowing, so that optimum GxM combinations could be informed. Here we test our capacity to inform that "hindsight", by linking a tested crop model (APSIM) with a skillful seasonal climate forecasting system, to answer "What is the value of the skill in seasonal climate forecasting, to inform crop designs?" Results showed that the GCM POAMA-2 was reliable and skillful, and that when linked with APSIM, optimum crop designs could be informed. We conclude that reliable and skillful GCMs that are easily interfaced with crop simulation models, can be used to inform optimum crop designs, increase farmers profits and reduce risks.
The rise and fall of social communities: Cascades of followers triggered by innovators
NASA Astrophysics Data System (ADS)
Hu, Yanqing; Havlin, Shlomo; Makse, Hernan
2013-03-01
New scientific ideas as well as key political messages, consumer products, advertisement strategies and art trends are originally adopted by a small number of pioneers who innovate and develop the ``new ideas''. When these innovators migrate to develop the novel idea, their former social network gradually weakens its grips as followers migrate too. As a result, an internal ``cascade of followers'' starts immediately thereafter speeding up the extinction of the entire original network. A fundamental problem in network theory is to determine the minimum number of pioneers that, upon leaving, will disintegrate their social network. Here, we first employ empirical analyses of collaboration networks of scientists to show that these communities are extremely fragile with regard to the departure of a few pioneers. This process can be mapped out on a percolation model in a correlated graph crucially augmented with outgoing ``influence links''. Analytical solutions predict phase transitions, either abrupt or continuous, where networks are disintegrated through cascades of followers as in the empirical data. The theory provides a framework to predict the vulnerability of a large class of networks containing influence links ranging from social and infrastructure networks to financial systems and markets.
Oxytonergic circuitry sustains and enables creative cognition in humans.
De Dreu, Carsten K W; Baas, Matthijs; Roskes, Marieke; Sligte, Daniel J; Ebstein, Richard P; Chew, Soo Hong; Tong, Terry; Jiang, Yushi; Mayseless, Naama; Shamay-Tsoory, Simone G
2014-08-01
Creativity enables humans to adapt flexibly to changing circumstances, to manage complex social relations and to survive and prosper through social, technological and medical innovations. In humans, chronic, trait-based as well as temporary, state-based approach orientation has been linked to increased capacity for divergent rather than convergent thinking, to more global and holistic processing styles and to more original ideation and creative problem solving. Here, we link creative cognition to oxytocin, a hypothalamic neuropeptide known to up-regulate approach orientation in both animals and humans. Study 1 (N = 492) showed that plasma oxytocin predicts novelty-seeking temperament. Study 2 (N = 110) revealed that genotype differences in a polymorphism in the oxytocin receptor gene rs1042778 predicted creative ideation, with GG/GT-carriers being more original than TT-carriers. Using double-blind placebo-controlled between-subjects designs, Studies 3-6 (N = 191) finally showed that intranasal oxytocin (vs matching placebo) reduced analytical reasoning, and increased holistic processing, divergent thinking and creative performance. We conclude that the oxytonergic circuitry sustains and enables the day-to-day creativity humans need for survival and prosperity and discuss implications. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Liu, Shuxin; Ji, Xinsheng; Liu, Caixia; Bai, Yi
2017-01-01
Many link prediction methods have been proposed for predicting the likelihood that a link exists between two nodes in complex networks. Among these methods, similarity indices are receiving close attention. Most similarity-based methods assume that the contribution of links with different topological structures is the same in the similarity calculations. This paper proposes a local weighted method, which weights the strength of connection between each pair of nodes. Based on the local weighted method, six local weighted similarity indices extended from unweighted similarity indices (including Common Neighbor (CN), Adamic-Adar (AA), Resource Allocation (RA), Salton, Jaccard and Local Path (LP) index) are proposed. Empirical study has shown that the local weighted method can significantly improve the prediction accuracy of these unweighted similarity indices and that in sparse and weakly clustered networks, the indices perform even better.
Oshri, Assaf; Himelboim, Itai; Kwon, Josephine A.; Sutton, Tara E.; Mackillop, James
2015-01-01
Objective: The aim of the present study was to examine the links between severities of child abuse (physical vs. sexual), and alcohol use versus problems via social media (Facebook) peer connection structures. Method: A total of 318 undergraduate female students at a public university in the United States reported severity of child abuse experiences and current alcohol use and problems. Social network data were obtained directly from the individuals’ Facebook network. Results: Severity of childhood physical abuse was positively linked to alcohol use and problems via eigenvector centrality, whereas severity of childhood sexual abuse was negatively linked to alcohol use and problems via clustering coefficient. Conclusions: Childhood physical and sexual abuse were linked positively and negatively, respectively, to online social network patterns associated with alcohol use and problems. The study suggests the potential utility of these online network patterns as risk indices and ultimately using social media as a platform for targeted preventive interventions. PMID:26562592
Oshri, Assaf; Himelboim, Itai; Kwon, Josephine A; Sutton, Tara E; Mackillop, James
2015-11-01
The aim of the present study was to examine the links between severities of child abuse (physical vs. sexual), and alcohol use versus problems via social media (Facebook) peer connection structures. A total of 318 undergraduate female students at a public university in the United States reported severity of child abuse experiences and current alcohol use and problems. Social network data were obtained directly from the individuals' Facebook network. Severity of childhood physical abuse was positively linked to alcohol use and problems via eigenvector centrality, whereas severity of childhood sexual abuse was negatively linked to alcohol use and problems via clustering coefficient. Childhood physical and sexual abuse were linked positively and negatively, respectively, to online social network patterns associated with alcohol use and problems. The study suggests the potential utility of these online network patterns as risk indices and ultimately using social media as a platform for targeted preventive interventions.
Suarez, Anna; Lahti, Jari; Czamara, Darina; Lahti-Pulkkinen, Marius; Knight, Anna K; Girchenko, Polina; Hämäläinen, Esa; Kajantie, Eero; Lipsanen, Jari; Laivuori, Hannele; Villa, Pia M; Reynolds, Rebecca M; Smith, Alicia K; Binder, Elisabeth B; Räikkönen, Katri
2018-05-01
Maternal antenatal depression may compromise the fetal developmental milieu and contribute to individual differences in aging and disease trajectories in later life. We evaluated the association between maternal antenatal depression and a novel biomarker of aging at birth, namely epigenetic gestational age (GA) based on fetal cord blood methylation data. We also examined whether this biomarker prospectively predicts and mediates maternal effects on early childhood psychiatric problems. A total of 694 mothers from the Prediction and Prevention of Preeclampsia and Intrauterine Growth Restriction (PREDO) Study provided information on history of depression diagnosed before pregnancy; 581 completed the Center for Epidemiological Studies Depression Scale throughout pregnancy, and 407 completed the Child Behavior Checklist at child's age 3.7 years (SD = 0.75 year). DNA methylation (DNAm) GA of fetal cord blood DNA was based on the methylation profile of 148 selected cytosine linked to guanine by phosphate (CpG) sites. Epigenetic GA was calculated as the arithmetic difference between DNAm GA and chronological GA and adjusted for chronological GA. Maternal history of depression diagnosed before pregnancy (mean difference = -0.25 SD units, 95% CI = -0.46 to -0.03) and greater antenatal depressive symptoms (-0.08 SD unit per 1-SD unit increase, 95% CI = -0.16 to -0.004) were associated with child's lower epigenetic GA. Child's lower epigenetic GA, in turn, prospectively predicted total and internalizing problems and partially mediated the effects of maternal antenatal depression on internalizing problems in boys. Maternal antenatal depression is associated with lower epigenetic GA in offspring. This lower epigenetic GA seems to be associated with a developmental disadvantage for boys, who, in early childhood, show greater psychiatric problems. Copyright © 2018 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.
Rothschild, Adam S.; Lehmann, Harold P.
2005-01-01
Objective: The aim of this study was to preliminarily determine the feasibility of probabilistically generating problem-specific computerized provider order entry (CPOE) pick-lists from a database of explicitly linked orders and problems from actual clinical cases. Design: In a pilot retrospective validation, physicians reviewed internal medicine cases consisting of the admission history and physical examination and orders placed using CPOE during the first 24 hours after admission. They created coded problem lists and linked orders from individual cases to the problem for which they were most indicated. Problem-specific order pick-lists were generated by including a given order in a pick-list if the probability of linkage of order and problem (PLOP) equaled or exceeded a specified threshold. PLOP for a given linked order-problem pair was computed as its prevalence among the other cases in the experiment with the given problem. The orders that the reviewer linked to a given problem instance served as the reference standard to evaluate its system-generated pick-list. Measurements: Recall, precision, and length of the pick-lists. Results: Average recall reached a maximum of .67 with a precision of .17 and pick-list length of 31.22 at a PLOP threshold of 0. Average precision reached a maximum of .73 with a recall of .09 and pick-list length of .42 at a PLOP threshold of .9. Recall varied inversely with precision in classic information retrieval behavior. Conclusion: We preliminarily conclude that it is feasible to generate problem-specific CPOE pick-lists probabilistically from a database of explicitly linked orders and problems. Further research is necessary to determine the usefulness of this approach in real-world settings. PMID:15684134
Lansford, Jennifer E.; Deater-Deckard, Kirby; Dodge, Kenneth A.; Bates, John E.; Pettit, Gregory S.
2009-01-01
Background Parents' use of physical discipline has generated controversy related to concerns that its use is associated with adjustment problems such as aggression and delinquency in children. However, recent evidence suggests that there are ethnic differences in associations between physical discipline and children's adjustment. This study examined race as a moderator of the link between physical discipline and adolescent externalizing behavior problems, extending previous research beyond childhood into adolescence and considering physical discipline at multiple points in time. Methods A representative community sample of 585 children was followed from pre-kindergarten (age 5) through grade 11 (age 16). Mothers reported on their use of physical discipline in the child's first five years of life and again during grades 6 (age 11) and 8 (age 13). Mothers and adolescents reported on a variety of externalizing behaviors in grade 11 including aggression, violence, and trouble at school and with the police. Results A series of hierarchical linear regressions controlling for parents' marital status, socioeconomic status, and child temperament revealed significant interactions between physical discipline during the child's first five years of life and race in the prediction of 3 of the 7 adolescent externalizing outcomes assessed and significant interactions between physical discipline during grades 6 and 8 and race in the prediction of all 7 adolescent externalizing outcomes. Regression slopes showed that the experience of physical discipline at each time point was related to higher levels of subsequent externalizing behaviors for European American adolescents but lower levels of externalizing behaviors for African American adolescents. Conclusions There are race differences in long-term effects of physical discipline on externalizing behaviors problems. Different ecological niches may affect the manner in which parents use physical discipline, the meaning that children attach to the experience of physical discipline, and its effects on the adjustment of children and adolescents. PMID:15056311
Measuring the value of accurate link prediction for network seeding.
Wei, Yijin; Spencer, Gwen
2017-01-01
The influence-maximization literature seeks small sets of individuals whose structural placement in the social network can drive large cascades of behavior. Optimization efforts to find the best seed set often assume perfect knowledge of the network topology. Unfortunately, social network links are rarely known in an exact way. When do seeding strategies based on less-than-accurate link prediction provide valuable insight? We introduce optimized-against-a-sample ([Formula: see text]) performance to measure the value of optimizing seeding based on a noisy observation of a network. Our computational study investigates [Formula: see text] under several threshold-spread models in synthetic and real-world networks. Our focus is on measuring the value of imprecise link information. The level of investment in link prediction that is strategic appears to depend closely on spread model: in some parameter ranges investments in improving link prediction can pay substantial premiums in cascade size. For other ranges, such investments would be wasted. Several trends were remarkably consistent across topologies.
Sleep problems and disability retirement: a register-based follow-up study.
Lallukka, Tea; Haaramo, Peija; Lahelma, Eero; Rahkonen, Ossi
2011-04-15
Among aging employees, sleep problems are prevalent, but they may have serious consequences that are poorly understood. This study examined whether sleep problems are associated with subsequent disability retirement. Baseline questionnaire survey data collected in 2000-2002 among employees of the city of Helsinki, Finland, were linked with register data on disability retirement diagnoses by the end of 2008 (n = 457) for those with written consent for such linkages (74%; N = 5,986). Sleep problems were measured by the Jenkins Sleep Questionnaire. Cox regression analysis was used to calculate hazard ratios and 95% confidence intervals for disability retirement. Gender- and age-adjusted frequent sleep problems predicted disability retirement due to all causes (hazard ratio (HR) = 3.22, 95% confidence interval (CI): 2.26, 4.60), mental disorders (HR = 9.06, 95% CI: 3.27, 25.10), and musculoskeletal disorders (HR = 3.27, 95% CI: 1.91, 5.61). Adjustments for confounders, that is, baseline sociodemographic factors, work arrangements, psychosocial working conditions, and sleep duration, had negligible effects on these associations, whereas baseline physical working conditions and health attenuated the associations. Health behaviors and obesity did not mediate the examined associations. In conclusion, sleep problems are associated with subsequent disability retirement. To prevent early exit from work, sleep problems among aging employees need to be addressed.
Buchanan, Verica; Lu, Yafeng; McNeese, Nathan; Steptoe, Michael; Maciejewski, Ross; Cooke, Nancy
2017-03-01
Historically, domains such as business intelligence would require a single analyst to engage with data, develop a model, answer operational questions, and predict future behaviors. However, as the problems and domains become more complex, organizations are employing teams of analysts to explore and model data to generate knowledge. Furthermore, given the rapid increase in data collection, organizations are struggling to develop practices for intelligence analysis in the era of big data. Currently, a variety of machine learning and data mining techniques are available to model data and to generate insights and predictions, and developments in the field of visual analytics have focused on how to effectively link data mining algorithms with interactive visuals to enable analysts to explore, understand, and interact with data and data models. Although studies have explored the role of single analysts in the visual analytics pipeline, little work has explored the role of teamwork and visual analytics in the analysis of big data. In this article, we present an experiment integrating statistical models, visual analytics techniques, and user experiments to study the role of teamwork in predictive analytics. We frame our experiment around the analysis of social media data for box office prediction problems and compare the prediction performance of teams, groups, and individuals. Our results indicate that a team's performance is mediated by the team's characteristics such as openness of individual members to others' positions and the type of planning that goes into the team's analysis. These findings have important implications for how organizations should create teams in order to make effective use of information from their analytic models.
Breeman, L D; Wubbels, T; van Lier, P A C; Verhulst, F C; van der Ende, J; Maras, A; Hopman, J A B; Tick, N T
2015-02-01
The goal of this study was to explore relations between teacher characteristics (i.e., competence and wellbeing); social classroom relationships (i.e., teacher-child and peer interactions); and children's social, emotional, and behavioral classroom adjustment. These relations were explored at both the individual and classroom levels among 414 children with emotional and behavioral disorders placed in special education. Two models were specified. In the first model, children's classroom adjustment was regressed on social relationships and teacher characteristics. In the second model, reversed links were examined by regressing teacher characteristics on social relationships and children's adjustment. Results of model 1 showed that, at the individual level, better social and emotional adjustment of children was predicted by higher levels of teacher-child closeness and better behavioral adjustment was predicted by both positive teacher-child and peer interactions. At the classroom level, positive social relationships were predicted by higher levels of teacher competence, which in turn were associated with lower classroom levels of social problems. Higher levels of teacher wellbeing were directly associated with classroom adaptive and maladaptive child outcomes. Results of model 2 showed that, at the individual and classroom levels, only the emotional and behavioral problems of children predicted social classroom relationships. At the classroom level, teacher competence was best predicted by positive teacher-child relationships and teacher wellbeing was best predicted by classroom levels of prosocial behavior. We discuss the importance of positive teacher-child and peer interactions for children placed in special education and suggest ways of improving classroom processes by targeting teacher competence. Copyright © 2014 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.
Conduct problems, IQ, and household chaos: a longitudinal multi-informant study
Deater-Deckard, Kirby; Mullineaux, Paula Y.; Beekman, Charles; Petrill, Stephen A.; Schatschneider, Chris; Thompson, Lee A.
2010-01-01
Background We tested the hypothesis that household chaos would be associated with lower child IQ and more child conduct problems concurrently and longitudinally over two years while controlling for housing conditions, parent education/IQ, literacy environment, parental warmth/negativity, and stressful events. Methods The sample included 302 families with same-sex twins (58% female) in Kindergarten/1st grade at the first assessment. Parents’ and observers’ ratings were gathered, with some collected over a two-year period. Results Chaos varied widely. There was substantial mother–father agreement and longitudinal stability. Chaos covaried with poorer housing conditions, lower parental education/IQ, poorer home literacy environment, higher stress, higher negativity and lower warmth. Chaos statistically predicted lower IQ and more conduct problems, beyond the effects of other home environment factors. Conclusions Even with other home environment factors controlled, higher levels of chaos were linked concurrently with lower child IQ, and concurrently and longitudinally with more child conduct problems. Parent self-reported chaos represents an important aspect of housing and family functioning, with respect to children’s cognitive and behavioral functioning. PMID:19527431
Lewis, Robin J; Mason, Tyler B; Winstead, Barbara A; Kelley, Michelle L
2017-01-01
This study proposed and tested the first conceptual model of sexual minority specific (discrimination, internalized homophobia) and more general risk factors (perpetrator and partner alcohol use, anger, relationship satisfaction) for intimate partner violence among partnered lesbian women. Self-identified lesbian women ( N =1048) were recruited from online market research panels. Participants completed an online survey that included measures of minority stress, anger, alcohol use and alcohol-related problems, relationship satisfaction, psychological aggression, and physical violence. The model demonstrated good fit and significant links from sexual minority discrimination to internalized homophobia and anger, from internalized homophobia to anger and alcohol problems, and from alcohol problems to intimate partner violence. Partner alcohol use predicted partner physical violence. Relationship dissatisfaction was associated with physical violence via psychological aggression. Physical violence was bidirectional. Minority stress, anger, alcohol use and alcohol-related problems play an important role in perpetration of psychological aggression and physical violence in lesbian women's intimate partner relationships. The results of this study provide evidence of potentially modifiable sexual minority specific and more general risk factors for lesbian women's partner violence.
Waller, Rebecca; Hyde, Luke W.; Baskin-Sommers, Arielle; Olson, Sheryl L.
2018-01-01
Callous unemotional (CU) behaviors are linked to aggression, behavior problems, and difficulties in peer relationships in children and adolescents. However, few studies have examined whether early childhood CU behaviors predict aggression or peer-rejection during late-childhood or potential moderation of this relationship by executive function. The current study examined whether the interaction of CU behaviors and executive function in early childhood predicted different forms of aggression in late-childhood, including proactive, reactive, and relational aggression, as well as how much children were liked by their peers. Data from cross-informant reports and multiple observational tasks were collected from a high-risk sample (N=240; female=118) at ages 3 and 10 years old. Parent reports of CU behaviors at age 3 predicted teacher reports of reactive, proactive, and relational aggression, as well as lower peer-liking at age 10. Moderation analysis showed that specifically at high levels of CU behaviors and low levels of observed executive function, children were reported by teachers as showing greater reactive and proactive aggression, and were less-liked by peers. Findings demonstrate that early childhood CU behaviors and executive function have unique main and interactive effects on both later aggression and lower peer-liking even when taking into account stability in behavior problems over time. By elucidating how CU behaviors and deficits in executive function potentiate each other during early childhood, we can better characterize the emergence of severe and persistent behavior and interpersonal difficulties across development. PMID:27418255
Inductive matrix completion for predicting gene-disease associations.
Natarajan, Nagarajan; Dhillon, Inderjit S
2014-06-15
Most existing methods for predicting causal disease genes rely on specific type of evidence, and are therefore limited in terms of applicability. More often than not, the type of evidence available for diseases varies-for example, we may know linked genes, keywords associated with the disease obtained by mining text, or co-occurrence of disease symptoms in patients. Similarly, the type of evidence available for genes varies-for example, specific microarray probes convey information only for certain sets of genes. In this article, we apply a novel matrix-completion method called Inductive Matrix Completion to the problem of predicting gene-disease associations; it combines multiple types of evidence (features) for diseases and genes to learn latent factors that explain the observed gene-disease associations. We construct features from different biological sources such as microarray expression data and disease-related textual data. A crucial advantage of the method is that it is inductive; it can be applied to diseases not seen at training time, unlike traditional matrix-completion approaches and network-based inference methods that are transductive. Comparison with state-of-the-art methods on diseases from the Online Mendelian Inheritance in Man (OMIM) database shows that the proposed approach is substantially better-it has close to one-in-four chance of recovering a true association in the top 100 predictions, compared to the recently proposed Catapult method (second best) that has <15% chance. We demonstrate that the inductive method is particularly effective for a query disease with no previously known gene associations, and for predicting novel genes, i.e. genes that are previously not linked to diseases. Thus the method is capable of predicting novel genes even for well-characterized diseases. We also validate the novelty of predictions by evaluating the method on recently reported OMIM associations and on associations recently reported in the literature. Source code and datasets can be downloaded from http://bigdata.ices.utexas.edu/project/gene-disease. © The Author 2014. Published by Oxford University Press.
The problem of the Grand Unification Theory
NASA Astrophysics Data System (ADS)
Treder, H.-J.
The evolution and fundamental questions of physical theories unifying the gravitational, electromagnetic, and quantum-mechanical interactions are explored, taking Pauli's aphorism as a motto: 'Let no man join what God has cast asunder.' The contributions of Faraday and Riemann, Lorentz, Einstein, and others are discussed, and the criterion of Pauli is applied to Grand Unification Theories (GUT) in general and to those seeking to link gravitation and electromagnetism in particular. Formal mathematical symmetry principles must be shown to have real physical relevance by predicting measurable phenomena not explainable without a GUT; these phenomena must be macroscopic because gravitational effects are to weak to be measured on the microscopic level. It is shown that empirical and theoretical studies of 'gravomagnetism', 'gravoelectricity', or possible links between gravoelectrity and the cosmic baryon assymmetry eventually lead back to basic questions which appear philosophical or purely mathematical but actually challenge physics to seek verifiable answers.
Towards in vivo focal cortical dysplasia phenotyping using quantitative MRI.
Adler, Sophie; Lorio, Sara; Jacques, Thomas S; Benova, Barbora; Gunny, Roxana; Cross, J Helen; Baldeweg, Torsten; Carmichael, David W
2017-01-01
Focal cortical dysplasias (FCDs) are a range of malformations of cortical development each with specific histopathological features. Conventional radiological assessment of standard structural MRI is useful for the localization of lesions but is unable to accurately predict the histopathological features. Quantitative MRI offers the possibility to probe tissue biophysical properties in vivo and may bridge the gap between radiological assessment and ex-vivo histology. This review will cover histological, genetic and radiological features of FCD following the ILAE classification and will explain how quantitative voxel- and surface-based techniques can characterise these features. We will provide an overview of the quantitative MRI measures available, their link with biophysical properties and finally the potential application of quantitative MRI to the problem of FCD subtyping. Future research linking quantitative MRI to FCD histological properties should improve clinical protocols, allow better characterisation of lesions in vivo and tailored surgical planning to the individual.
Azar, Sandra T; Miller, Elizabeth A; Stevenson, Michael T; Johnson, David R
2017-08-01
Inadequate supervision has been linked to children's injuries. Parental injury prevention beliefs may play a role in supervision, yet little theory has examined the origins of such beliefs. This study examined whether mothers who perpetrated child neglect, who as a group provide inadequate supervision, have more maladaptive beliefs. Then, it tested a social information processing (SIP) model for explaining these beliefs. SIP and injury prevention beliefs were assessed in disadvantaged mothers of preschoolers (N = 145), half with child neglect histories. The neglect group exhibited significantly more maladaptive injury prevention beliefs than comparisons. As predicted, SIP was linked to beliefs that may increase injury risk, even after accounting for relevant sociodemographic variables. Findings support the link of beliefs to injury risk and suggest that specific cognitive problems may underlie these beliefs. Future work should further validate this model, which may inform enhancements to prevention efforts. © The Author 2016. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com
Effects of expertise on football betting.
Khazaal, Yasser; Chatton, Anne; Billieux, Joël; Bizzini, Lucio; Monney, Grégoire; Fresard, Emmanuelle; Thorens, Gabriel; Bondolfi, Guido; El-Guebaly, Nady; Zullino, Daniele; Khan, Riaz
2012-05-11
Football (soccer) is one of the most popular sports in the world, including Europe. It is associated with important betting activities. A common belief, widely spread among those who participate in gambling activities, is that knowledge and expertise on football lead to better prediction skills for match outcomes. If unfounded, however, this belief should be considered as a form of "illusion of control." The aim of this study was to examine whether football experts are better than nonexperts at predicting football match scores. Two hundred and fifty-eight persons took part in the study: 21.3% as football experts, 54.3% as laypersons (non-initiated to football), and 24.4% as football amateurs. They predicted the scores of the first 10 matches of the 2008 UEFA European Football Championship. Logistic regressions were carried out to assess the link between the accuracy of the forecasted scores and the expertise of the participants (expert, amateur, layperson), controlling for age and gender. The variables assessed did not predict the accuracy of scoring prognosis (R2 ranged from 1% to 6%). Expertise, age, and gender did not appear to have an impact on the accuracy of the football match prognoses. Therefore, the belief that football expertise improves betting skills is no more than a cognitive distortion called the "illusion of control." Gamblers may benefit from psychological interventions that target the illusion of control related to their believed links between betting skills and football expertise. Public health policies may need to consider the phenomenon in order to prevent problem gambling related to football betting.
PRELIM: Predictive Relevance Estimation from Linked Models
2014-10-14
code ) 14-10-2014 Final Report 11-07-2014 to 14-10-2014 PRELIM: Predictive Relevance Estimation from Linked Models N00014-14-P-1185 10257H. Van Dyke...Parunak, Ph.D. Soar Technology, Inc. 1 Executive Summary PRELIM (Predictive Relevance Estimation from Linked Models) draws on semantic models...The central challenge in proactive decision support is to anticipate the decision and information needs of decision-makers, in the light of likely
2008-10-17
R E 1960 A new approach to linear filtering and prediction problems Trans. ASME D 82 35–45 [23] Brown R G and Hwang Y C 1992 Introduction to Random...vector Wiener filter [21]. TDSI is also somewhat similar to the Kalman filter [22, 23] which is applied in many areas including tomography [24–27]. The...453–76 [21] Links J M, Prince J L and Gupta S N 1996 A vector Wiener filter for dual-radionuclide imaging IEEE Trans. Med. Imaging 15 700–9 [22] Kalman
Fast Katz and Commuters: Efficient Estimation of Social Relatedness in Large Networks
NASA Astrophysics Data System (ADS)
Esfandiar, Pooya; Bonchi, Francesco; Gleich, David F.; Greif, Chen; Lakshmanan, Laks V. S.; On, Byung-Won
Motivated by social network data mining problems such as link prediction and collaborative filtering, significant research effort has been devoted to computing topological measures including the Katz score and the commute time. Existing approaches typically approximate all pairwise relationships simultaneously. In this paper, we are interested in computing: the score for a single pair of nodes, and the top-k nodes with the best scores from a given source node. For the pairwise problem, we apply an iterative algorithm that computes upper and lower bounds for the measures we seek. This algorithm exploits a relationship between the Lanczos process and a quadrature rule. For the top-k problem, we propose an algorithm that only accesses a small portion of the graph and is related to techniques used in personalized PageRank computing. To test the scalability and accuracy of our algorithms we experiment with three real-world networks and find that these algorithms run in milliseconds to seconds without any preprocessing.
Gray, Sarah A O; Carter, Alice S; Briggs-Gowan, Margaret J; Jones, Stephanie M; Wagmiller, Robert L
2014-09-01
The link between behavior problems and low academic achievement is well established, but few studies have examined longitudinal relations between early externalizing behaviors before school entry and low academic achievement following transition to formal schooling. Early inattention has been particularly overlooked, despite strong associations between inattention and reading difficulties later in development. Trajectories of infant and toddler aggression, overactivity, and inattention, developed from parent reports about 1- to 3-year-old children, were examined as predictors of direct assessments of 2nd-grade reading in an at-risk epidemiological study subsample (N = 359). Reports of inattentive and overactive behaviors at ages 1-3 years and changes in inattention through toddlerhood predicted reading achievement in 2nd grade. A parallel process model suggested that the effects of early inattention on reading appear to be most robust. Findings underscore the contribution of social-emotional development to school readiness and the importance of early identification of children with externalizing problems, as early interventions designed to reduce externalizing problems may improve later reading skills.
Gray, Sarah A. O.; Carter, Alice S.; Briggs-Gowan, Margaret J.; Jones, Stephanie M.; Wagmiller, Robert L.
2015-01-01
The link between behavior problems and low academic achievement is well established, but few studies have examined longitudinal relations between early externalizing behaviors before school entry and low academic achievement following transition to formal schooling. Early inattention has been particularly overlooked, despite strong associations between inattention and reading difficulties later in development. Trajectories of infant/toddler aggression, overactivity, and inattention, developed from parent reports about 1- to 3-year-old children, were examined as predictors of direct assessments of second grade reading in an at-risk epidemiological study subsample (N = 359). Reports of inattentive and overactive behaviors at age 1-to-3 years and changes in inattention through toddlerhood predicted reading achievement in second grade. A parallel process model suggested that the effects of early inattention on reading appear to be most robust. Findings underscore the contribution of social-emotional development to school readiness and the importance of early identification of children with externalizing problems, as early interventions designed to reduce externalizing problems may improve later reading skills. PMID:25046126
Hippocampal-neocortical functional reorganization underlies children's cognitive development.
Qin, Shaozheng; Cho, Soohyun; Chen, Tianwen; Rosenberg-Lee, Miriam; Geary, David C; Menon, Vinod
2014-09-01
The importance of the hippocampal system for rapid learning and memory is well recognized, but its contributions to a cardinal feature of children's cognitive development-the transition from procedure-based to memory-based problem-solving strategies-are unknown. Here we show that the hippocampal system is pivotal to this strategic transition. Longitudinal functional magnetic resonance imaging (fMRI) in 7-9-year-old children revealed that the transition from use of counting to memory-based retrieval parallels increased hippocampal and decreased prefrontal-parietal engagement during arithmetic problem solving. Longitudinal improvements in retrieval-strategy use were predicted by increased hippocampal-neocortical functional connectivity. Beyond childhood, retrieval-strategy use continued to improve through adolescence into adulthood and was associated with decreased activation but more stable interproblem representations in the hippocampus. Our findings provide insights into the dynamic role of the hippocampus in the maturation of memory-based problem solving and establish a critical link between hippocampal-neocortical reorganization and children's cognitive development.
Fast katz and commuters : efficient estimation of social relatedness in large networks.
DOE Office of Scientific and Technical Information (OSTI.GOV)
On, Byung-Won; Lakshmanan, Laks V. S.; Greif, Chen
Motivated by social network data mining problems such as link prediction and collaborative filtering, significant research effort has been devoted to computing topological measures including the Katz score and the commute time. Existing approaches typically approximate all pairwise relationships simultaneously. In this paper, we are interested in computing: the score for a single pair of nodes, and the top-k nodes with the best scores from a given source node. For the pairwise problem, we apply an iterative algorithm that computes upper and lower bounds for the measures we seek. This algorithm exploits a relationship between the Lanczos process and amore » quadrature rule. For the top-k problem, we propose an algorithm that only accesses a small portion of the graph and is related to techniques used in personalized PageRank computing. To test the scalability and accuracy of our algorithms we experiment with three real-world networks and find that these algorithms run in milliseconds to seconds without any preprocessing.« less
Human Gut Microbiota Predicts Susceptibility to Vibrio cholerae Infection.
Midani, Firas S; Weil, Ana A; Chowdhury, Fahima; Begum, Yasmin A; Khan, Ashraful I; Debela, Meti D; Durand, Heather K; Reese, Aspen T; Nimmagadda, Sai N; Silverman, Justin D; Ellis, Crystal N; Ryan, Edward T; Calderwood, Stephen B; Harris, Jason B; Qadri, Firdausi; David, Lawrence A; LaRocque, Regina C
2018-04-12
Cholera is a public health problem worldwide and the risk factors for infection are only partially understood. We prospectively studied household contacts of cholera patients to compare those who were infected with those who were not. We constructed predictive machine learning models of susceptibility using baseline gut microbiota data. We identified bacterial taxa associated with susceptibility to Vibrio cholerae infection and tested these taxa for interactions with V. cholerae in vitro. We found that machine learning models based on gut microbiota predicted V. cholerae infection as well as models based on known clinical and epidemiological risk factors. A 'predictive gut microbiota' of roughly 100 bacterial taxa discriminated between contacts who developed infection and those who did not. Susceptibility to cholera was associated with depleted levels of microbes from the phylum Bacteroidetes. By contrast, a microbe associated with cholera by our modeling framework, Paracoccus aminovorans, promoted the in vitro growth of V. cholerae. Gut microbiota structure, clinical outcome, and age were also linked. These findings support the hypothesis that abnormal gut microbial communities are a host factor related to V. cholerae susceptibility.
Modelling Chemical Reasoning to Predict and Invent Reactions.
Segler, Marwin H S; Waller, Mark P
2017-05-02
The ability to reason beyond established knowledge allows organic chemists to solve synthetic problems and invent novel transformations. Herein, we propose a model that mimics chemical reasoning, and formalises reaction prediction as finding missing links in a knowledge graph. We have constructed a knowledge graph containing 14.4 million molecules and 8.2 million binary reactions, which represents the bulk of all chemical reactions ever published in the scientific literature. Our model outperforms a rule-based expert system in the reaction prediction task for 180 000 randomly selected binary reactions. The data-driven model generalises even beyond known reaction types, and is thus capable of effectively (re-)discovering novel transformations (even including transition metal-catalysed reactions). Our model enables computers to infer hypotheses about reactivity and reactions by only considering the intrinsic local structure of the graph and because each single reaction prediction is typically achieved in a sub-second time frame, the model can be used as a high-throughput generator of reaction hypotheses for reaction discovery. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Pellicano, Elizabeth
2010-03-01
There is strong evidence to suggest that individuals with autism show atypicalities in multiple cognitive domains, including theory of mind (ToM), executive function (EF), and central coherence (CC). In this study, the longitudinal relationships among these 3 aspects of cognition in autism were investigated. Thirty-seven cognitively able children with an autism spectrum condition were assessed on tests targeting ToM (false-belief prediction), EF (planning ability, cognitive flexibility, and inhibitory control), and CC (local processing) at intake and again 3 years later. Time 1 EF and CC skills were longitudinally predictive of change in children's ToM test performance, independent of age, language, nonverbal intelligence, and early ToM skills. Predictive relations in the opposite direction were not significant, and there were no developmental links between EF and CC. Rather than showing problems in ToM, EF and CC as co-occurring and independent atypicalities in autism, these findings suggest that early domain-general skills play a critical role in shaping the developmental trajectory of children's ToM.
Perren, Sonja; Ettekal, Idean; Ladd, Gary
2012-01-01
Background Evidence indicates that being a victim of bullying or peer aggression has negative short- and long-term consequences. In this study, we investigated the mediating and moderating role of two types of attributional mechanisms (hostile and self-blaming attributions) on children’s maladjustment (externalizing and internalizing problems). Methods In total, 478 children participated in this longitudinal study from grade 5 to grade 7. Children, parents and teachers repeatedly completed questionnaires. Peer victimization was assessed through peer reports (T1). Attributions were assessed through self-reports using hypothetical scenarios (T2). Parents and teachers reported on children’s maladjustment (T1 and T3). Results Peer victimization predicted increases in externalizing and internalizing problems. Hostile attributions partially mediated the impact of victimization on increases in externalizing problems. Self-blame was not associated with peer victimization. However, for children with higher levels of self-blaming attributions, peer victimization was linked more strongly with increases in internalizing problems. Conclusions Results imply that hostile attributions may operate as a potential mechanism through which negative experiences with peers lead to increases in children’s aggressive and delinquent behavior, whereas self-blame exacerbates victimization’s effects on internalizing problems. PMID:23057732
Emotional Desensitization to Violence Contributes to Adolescents' Violent Behavior.
Mrug, Sylvie; Madan, Anjana; Windle, Michael
2016-01-01
Many adolescents are exposed to violence in their schools, communities and homes. Exposure to violence at high levels or across multiple contexts has been linked with emotional desensitization, indicated by low levels of internalizing symptoms. However, the long-term consequences of such desensitization are unknown. This study examined emotional desensitization to violence, together with externalizing problems, as mediators of the relationship between exposure to violence in pre-adolescence and violent behavior in late adolescence. A community sample of youth (N = 704; 48% female; 76% African American, 22% Caucasian) reported on their exposure to violence in multiple settings at ages 11, 13 and 18. Internalizing and externalizing problems were assessed at ages 11 and 13; violent behavior was measured at age 18. Structural Equation Modeling showed that exposure to high levels of violence at age 11 was associated with lower levels of internalizing problems (quadratic effect) at age 13, as was exposure to violence across multiple contexts (linear effect). In turn, fewer internalizing problems and more externalizing problems at age 13 predicted more violent behavior at age 18. The results suggest that emotional desensitization to violence in early adolescence contributes to serious violence in late adolescence.
Emotional Desensitization to Violence Contributes to Adolescents’ Violent Behavior
Mrug, Sylvie; Madan, Anjana; Windle, Michael
2015-01-01
Many adolescents are exposed to violence in their schools, communities and homes. Exposure to violence at high levels or across multiple contexts has been linked with emotional desensitization, indicated by low levels of internalizing symptoms. However, the long-term consequences of such desensitization are unknown. This study examined emotional desensitization to violence, together with externalizing problems, as mediators of the relationship between exposure to violence in pre-adolescence and violent behavior in late adolescence. A community sample of youth (N=704; 48% female; 76% African American, 22% Caucasian) reported on their exposure to violence in multiple settings at ages 11, 13 and 18. Internalizing and externalizing problems were assessed at ages 11 and 13; violent behavior was measured at age 18. Structural Equation Modeling showed that exposure to high levels of violence at age 11 was associated with lower levels of internalizing problems (quadratic effect) at age 13, as was exposure to violence across multiple contexts (linear effect). In turn, fewer internalizing problems and more externalizing problems at age 13 predicted more violent behavior at age 18. The results suggest that emotional desensitization to violence in early adolescence contributes to serious violence in late adolescence. PMID:25684447
Savundranayagam, Marie Y; Orange, J B
2011-11-01
The purpose of this study was to investigate the impact of caregivers' appraisals of the effectiveness of their own communication strategies on caregiver burden when caring for family members with Alzheimer's disease (AD). Family caregivers (N = 84) of participants with AD completed questionnaires appraising communication strategies, problem behaviors, and levels of three types of burden. Hierarchical linear regression models revealed that effective strategies and kinship status were significantly linked with stress burden, whereas effective strategies and problem behaviors were significantly related to relationship burden. Cognitive status of participants with AD significantly predicted objective burden. Caregivers who rated effective strategies as helpful were more likely to experience lower levels of stress and relationship burden. Findings provide preliminary support for understanding mechanisms by which the appraisals of communication strategies influence caregiver burden and justify testing empirically derived communication interventions.
CisMapper: predicting regulatory interactions from transcription factor ChIP-seq data
O'Connor, Timothy; Bodén, Mikael
2017-01-01
Abstract Identifying the genomic regions and regulatory factors that control the transcription of genes is an important, unsolved problem. The current method of choice predicts transcription factor (TF) binding sites using chromatin immunoprecipitation followed by sequencing (ChIP-seq), and then links the binding sites to putative target genes solely on the basis of the genomic distance between them. Evidence from chromatin conformation capture experiments shows that this approach is inadequate due to long-distance regulation via chromatin looping. We present CisMapper, which predicts the regulatory targets of a TF using the correlation between a histone mark at the TF's bound sites and the expression of each gene across a panel of tissues. Using both chromatin conformation capture and differential expression data, we show that CisMapper is more accurate at predicting the target genes of a TF than the distance-based approaches currently used, and is particularly advantageous for predicting the long-range regulatory interactions typical of tissue-specific gene expression. CisMapper also predicts which TF binding sites regulate a given gene more accurately than using genomic distance. Unlike distance-based methods, CisMapper can predict which transcription start site of a gene is regulated by a particular binding site of the TF. PMID:28204599
Automatic Invocation Linking for Collaborative Web-Based Corpora
NASA Astrophysics Data System (ADS)
Gardner, James; Krowne, Aaron; Xiong, Li
Collaborative online encyclopedias or knowledge bases such as Wikipedia and PlanetMath are becoming increasingly popular because of their open access, comprehensive and interlinked content, rapid and continual updates, and community interactivity. To understand a particular concept in these knowledge bases, a reader needs to learn about related and underlying concepts. In this chapter, we introduce the problem of invocation linking for collaborative encyclopedia or knowledge bases, review the state of the art for invocation linking including the popular linking system of Wikipedia, discuss the problems and challenges of automatic linking, and present the NNexus approach, an abstraction and generalization of the automatic linking system used by PlanetMath.org. The chapter emphasizes both research problems and practical design issues through discussion of real world scenarios and hence is suitable for both researchers in web intelligence and practitioners looking to adopt the techniques. Below is a brief outline of the chapter.
Visualizing Internet routing changes.
Lad, Mohit; Massey, Dan; Zhang, Lixia
2006-01-01
Today's Internet provides a global data delivery service to millions of end users and routing protocols play a critical role in this service. It is important to be able to identify and diagnose any problems occurring in Internet routing. However, the Internet's sheer size makes this task difficult. One cannot easily extract out the most important or relevant routing information from the large amounts of data collected from multiple routers. To tackle this problem, we have developed Link-Rank, a tool to visualize Internet routing changes at the global scale. Link-Rank weighs links in a topological graph by the number of routes carried over each link and visually captures changes in link weights in the form of a topological graph with adjustable size. Using Link-Rank, network operators can easily observe important routing changes from massive amounts of routing data, discover otherwise unnoticed routing problems, understand the impact of topological events, and infer root causes of observed routing changes.
Statistical similarity measures for link prediction in heterogeneous complex networks
NASA Astrophysics Data System (ADS)
Shakibian, Hadi; Charkari, Nasrollah Moghadam
2018-07-01
The majority of the link prediction measures in heterogeneous complex networks rely on the nodes connectivities while less attention has been paid to the importance of the nodes and paths. In this paper, we propose some new meta-path based statistical similarity measures to properly perform link prediction task. The main idea in the proposed measures is to drive some co-occurrence events in a number of co-occurrence matrices that are occurred between the visited nodes obeying a meta-path. The extracted co-occurrence matrices are analyzed in terms of the energy, inertia, local homogeneity, correlation, and information measure of correlation to determine various information theoretic measures. We evaluate the proposed measures, denoted as link energy, link inertia, link local homogeneity, link correlation, and link information measure of correlation, using a standard DBLP network data set. The results of the AUC score and Precision rate indicate the validity and accuracy of the proposed measures in comparison to the popular meta-path based similarity measures.
Childhood Maltreatment Predicts Allostatic Load in Adulthood
Widom, Cathy Spatz; Horan, Jacqueline; Brzustowicz, Linda
2015-01-01
Childhood maltreatment has been linked to numerous negative health outcomes. However, few studies have examined mediating processes using longitudinal designs or objectively measured biological data. This study sought to determine whether child abuse and neglect predicts allostatic load (a composite indicator of accumulated stress-induced biological risk) and to examine potential mediators. Using a prospective cohort design, children (ages 0-11) with documented cases of abuse and neglect were matched with non-maltreated children and followed up into adulthood with in-person interviews and a medical status exam (mean age 41). Allostatic load was assessed with nine physical health indicators. Child abuse and neglect predicted allostatic load, controlling for age, sex, and race. The direct effect of child abuse and neglect persisted despite the introduction of potential mediators of internalizing and externalizing problems in adolescence and social support and risky lifestyle in middle adulthood. These findings reveal the long-term impact of childhood abuse and neglect on physical health over 30 years later. PMID:25700779
Female Pubertal Timing and Problem Behaviour: The Role of Culture
ERIC Educational Resources Information Center
Skoog, Therese; Stattin, Hakan; Ruiselova, Zdena; Ozdemir, Metin
2013-01-01
We tested the peer-socialization/contextual-amplification explanation for the link between early female puberty and problem behaviour. We propose that in cultures with high tolerance for adolescent heterosexual involvement, early puberty should be linked with problem behaviour--not in other cultures. We compared girls in two cultures (Slovakia and…
Predicting protein-protein interactions from protein domains using a set cover approach.
Huang, Chengbang; Morcos, Faruck; Kanaan, Simon P; Wuchty, Stefan; Chen, Danny Z; Izaguirre, Jesús A
2007-01-01
One goal of contemporary proteome research is the elucidation of cellular protein interactions. Based on currently available protein-protein interaction and domain data, we introduce a novel method, Maximum Specificity Set Cover (MSSC), for the prediction of protein-protein interactions. In our approach, we map the relationship between interactions of proteins and their corresponding domain architectures to a generalized weighted set cover problem. The application of a greedy algorithm provides sets of domain interactions which explain the presence of protein interactions to the largest degree of specificity. Utilizing domain and protein interaction data of S. cerevisiae, MSSC enables prediction of previously unknown protein interactions, links that are well supported by a high tendency of coexpression and functional homogeneity of the corresponding proteins. Focusing on concrete examples, we show that MSSC reliably predicts protein interactions in well-studied molecular systems, such as the 26S proteasome and RNA polymerase II of S. cerevisiae. We also show that the quality of the predictions is comparable to the Maximum Likelihood Estimation while MSSC is faster. This new algorithm and all data sets used are accessible through a Web portal at http://ppi.cse.nd.edu.
Eronen, Lauri; Toivonen, Hannu
2012-06-06
Biological databases contain large amounts of data concerning the functions and associations of genes and proteins. Integration of data from several such databases into a single repository can aid the discovery of previously unknown connections spanning multiple types of relationships and databases. Biomine is a system that integrates cross-references from several biological databases into a graph model with multiple types of edges, such as protein interactions, gene-disease associations and gene ontology annotations. Edges are weighted based on their type, reliability, and informativeness. We present Biomine and evaluate its performance in link prediction, where the goal is to predict pairs of nodes that will be connected in the future, based on current data. In particular, we formulate protein interaction prediction and disease gene prioritization tasks as instances of link prediction. The predictions are based on a proximity measure computed on the integrated graph. We consider and experiment with several such measures, and perform a parameter optimization procedure where different edge types are weighted to optimize link prediction accuracy. We also propose a novel method for disease-gene prioritization, defined as finding a subset of candidate genes that cluster together in the graph. We experimentally evaluate Biomine by predicting future annotations in the source databases and prioritizing lists of putative disease genes. The experimental results show that Biomine has strong potential for predicting links when a set of selected candidate links is available. The predictions obtained using the entire Biomine dataset are shown to clearly outperform ones obtained using any single source of data alone, when different types of links are suitably weighted. In the gene prioritization task, an established reference set of disease-associated genes is useful, but the results show that under favorable conditions, Biomine can also perform well when no such information is available.The Biomine system is a proof of concept. Its current version contains 1.1 million entities and 8.1 million relations between them, with focus on human genetics. Some of its functionalities are available in a public query interface at http://biomine.cs.helsinki.fi, allowing searching for and visualizing connections between given biological entities.
A Complex Systems Model Approach to Quantified Mineral Resource Appraisal
Gettings, M.E.; Bultman, M.W.; Fisher, F.S.
2004-01-01
For federal and state land management agencies, mineral resource appraisal has evolved from value-based to outcome-based procedures wherein the consequences of resource development are compared with those of other management options. Complex systems modeling is proposed as a general framework in which to build models that can evaluate outcomes. Three frequently used methods of mineral resource appraisal (subjective probabilistic estimates, weights of evidence modeling, and fuzzy logic modeling) are discussed to obtain insight into methods of incorporating complexity into mineral resource appraisal models. Fuzzy logic and weights of evidence are most easily utilized in complex systems models. A fundamental product of new appraisals is the production of reusable, accessible databases and methodologies so that appraisals can easily be repeated with new or refined data. The data are representations of complex systems and must be so regarded if all of their information content is to be utilized. The proposed generalized model framework is applicable to mineral assessment and other geoscience problems. We begin with a (fuzzy) cognitive map using (+1,0,-1) values for the links and evaluate the map for various scenarios to obtain a ranking of the importance of various links. Fieldwork and modeling studies identify important links and help identify unanticipated links. Next, the links are given membership functions in accordance with the data. Finally, processes are associated with the links; ideally, the controlling physical and chemical events and equations are found for each link. After calibration and testing, this complex systems model is used for predictions under various scenarios.
Marek, Ryan J; Block, Andrew R; Ben-Porath, Yossef S
2015-03-01
A substantial proportion of individuals who undergo surgical procedures to relieve spine pain continue to report significant pain and dysfunction after recovery. Psychopathology and patient expectations have been linked to poor results, leading to an increasing reliance on presurgical psychological screening (PPS) as part of the surgical diagnostic process. The original Minnesota Multiphasic Personality Inventory (MMPI; Hathaway & McKinley, 1943) and the MMPI-2 (Butcher, Graham, Ben-Porath, Tellegen, & Dahlstrom, 2001) were among the measures most commonly used in PPS evaluations and research. This study focuses on the newest version of the test, the MMPI-2-Restructured Form (MMPI-2-RF; Ben-Porath & Tellegen, 2008/2011; Tellegen & Ben-Porath, 2008/2011) as a predictor of outcomes for spine surgery candidates. Using a sample of 172 men and 210 women who underwent a PPS, we examined the ability of MMPI-2-RF scale scores to predict early surgical outcomes independent of other presurgical risk factors identified by other means, as well as patients' presurgical expectations. MMPI-2-RF results accounted for up to 11% of additional variance in measures of early postoperative functioning. MMPI-2-RF scales that assess for emotional/internalizing problems, specifically Demoralization, measures of somatoform dysfunction, and interpersonal problems contributed most to the prediction of diminished outcome. 2015 APA, all rights reserved
Preschoolers’ Psychopathology and Temperament Predict Mothers’ Later Mood Disorders
Allmann, Anna E.S.; Kopala-Sibley, Daniel C.; Klein, Daniel N.
2017-01-01
Considerable research exists documenting the relationship between maternal mood disorders, primarily major depressive disorder (MDD), and a variety of negative child outcomes. By contrast, research exploring the reverse pathway whereby child traits are associated with later maternal mood disorders is much more limited. We examined whether young children’s temperament and psychopathology predicted maternal mood disorders approximately 6 years later. Child temperament and symptoms were assessed at age three using semi-structured diagnostic interviews and parent-report inventories. Maternal psychopathology was assessed with semi-structured interviews when children were three and nine years old. Mothers also reported on their marital satisfaction when children were three and six years old. Child temperamental negative affectivity (NA), depressive symptoms, and externalizing behavior problems significantly predicted maternal mood disorders over and above prior maternal mood, anxiety, and substance disorders. The link between children’s early externalizing symptoms and maternal mood disorders 6 years later was mediated by maternal marital satisfaction 3 years after the initial assessment. These findings suggest that early child temperament and psychopathology contribute to risk for later maternal mood disorders both directly and through their impact on the marital system. Research indicates that effective treatment of maternal depression is associated with positive outcomes for children; however, this study suggests that treating early child problems may mitigate the risk of later maternal psychopathology. PMID:26219263
Heberle, Amy E.; Krill, Sarah C.; Briggs-Gowan, Margaret J.; Carter, Alice S.
2014-01-01
Objective This study tested an ecological model predicting children’s behavior problems in kindergarten from risk and protective factors (parent psychological distress, parenting behavior, and social support) during early childhood. Method Study participants were 1161 socio-demographically diverse mother-child pairs who participated in a longitudinal birth cohort study. The predictor variables were collected at two separate time points and based on parent reports; children were an average of two years old at Time 1 and three years old at Time 2. The outcome measures were collected when children reached Kindergarten and were six years old on average. Results Our results show that early maternal psychological distress, mediated by sub-optimal parenting behavior, predicts children’s externalizing and internalizing behaviors in kindergarten. Moreover, early social support buffers the relations between psychological distress and later sub-optimal parenting behaviors and between sub-optimal parenting behavior and later depressive/withdrawn behavior. Conclusions Our findings have several implications for early intervention and prevention efforts. Of note, informal social support appears to play an important protective role in the development of externalizing and internalizing behavior problems, weakening the link between psychological distress and less optimal parenting behavior and between sub-optimal parenting behavior and children’s withdrawal/depression symptoms. Increasing social support may be a productive goal for family and community-level intervention. PMID:24697587
Workplace harassment, active coping, and alcohol-related outcomes.
Richman, J A; Rospenda, K M; Flaherty, J A; Freels, S
2001-01-01
While sexual harassment and generalized workplace abuse (GWA) have been linked with alcohol use and abuse, active problem-focused coping has been shown to lessen vulnerability to deleterious mental health consequences of varied social stressors. At the same time, active coping is relatively more efficacious in response to stressors, which are amenable to change by personal actions. However, the moderating role that coping plays in relation to harassment and drinking is unknown. Using data from a two-wave survey of university employees (N=2038), we addressed the extent to which (1) active coping was utilized by harassed and abused employees, (2) whether coping impacted on the continuation or cessation of harassment and abuse, and (3) the extent to which nonsuccessful coping was predictive of alcohol use and abuse. Active coping had no significant impact on the ability to end harassing or abusive experiences. Moreover, the use of problem-focused coping that was unsuccessful predicted some drinking outcomes for both men and women, controlling for Wave I drinking and sociodemographic characteristics. The data suggest that increased institutional attention to the prevention of workplace harassment and abuse might impact on decreasing alcohol use and abuse.
Haller, Moira; Chassin, Laurie
2014-09-01
The present study utilized longitudinal data from a community sample (n = 377; 166 trauma-exposed; 54% males; 73% non-Hispanic Caucasian; 22% Hispanic; 5% other ethnicity) to test whether pretrauma substance use problems increase risk for trauma exposure (high-risk hypothesis) or posttraumatic stress disorder (PTSD) symptoms (susceptibility hypothesis), whether PTSD symptoms increase risk for later alcohol/drug problems (self-medication hypothesis), and whether the association between PTSD symptoms and alcohol/drug problems is attributable to shared risk factors (shared vulnerability hypothesis). Logistic and negative binomial regressions were performed in a path analysis framework. Results provided the strongest support for the self-medication hypothesis, such that PTSD symptoms predicted higher levels of later alcohol and drug problems, over and above the influences of pretrauma family risk factors, pretrauma substance use problems, trauma exposure, and demographic variables. Results partially supported the high-risk hypothesis, such that adolescent substance use problems increased risk for assaultive violence exposure but did not influence overall risk for trauma exposure. There was no support for the susceptibility hypothesis. Finally, there was little support for the shared vulnerability hypothesis. Neither trauma exposure nor preexisting family adversity accounted for the link between PTSD symptoms and later substance use problems. Rather, PTSD symptoms mediated the effect of pretrauma family adversity on later alcohol and drug problems, thereby supporting the self-medication hypothesis. These findings make important contributions to better understanding the directions of influence among traumatic stress, PTSD symptoms, and substance use problems.
Strömberg, Carl; Aboagye, Emmanuel; Hagberg, Jan; Bergström, Gunnar; Lohela-Karlsson, Malin
2017-09-01
The aim of this study was to propose wage multipliers that can be used to estimate the costs of productivity loss for employers in economic evaluations, using detailed information from managers. Data were collected in a survey panel of 758 managers from different sectors of the labor market. Based on assumed scenarios of a period of absenteeism due to sickness, presenteeism and work environment-related problem episodes, and specified job characteristics (i.e., explanatory variables), managers assessed their impact on group productivity and cost (i.e., the dependent variable). In an ordered probit model, the extent of productivity loss resulting from job characteristics is predicted. The predicted values are used to derive wage multipliers based on the cost of productivity estimates provided by the managers. The results indicate that job characteristics (i.e., degree of time sensitivity of output, teamwork, or difficulty in replacing a worker) are linked to productivity loss as a result of health-related and work environment-related problems. The impact of impaired performance on productivity differs among various occupations. The mean wage multiplier is 1.97 for absenteeism, 1.70 for acute presenteeism, 1.54 for chronic presenteeism, and 1.72 for problems related to the work environment. This implies that the costs of health-related and work environment-related problems to organizations can exceed the worker's wage. The use of wage multipliers is recommended for calculating the cost of health-related and work environment-related productivity loss to properly account for actual costs. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Tseng, Wan-Ling; Gau, Susan Shur-Fen
2013-01-01
Background: Cognitive processes and mechanisms underlying the strong link between attention-deficit/hyperactivity disorder (ADHD) and social problems remain unclear. Limited knowledge also exists regarding a subgroup of youth with ADHD who do not have social problems. This study investigated the extent to which executive function (EF) mediated the…
NASA Astrophysics Data System (ADS)
Gill, G.; Sakrani, T.; Cheng, W.; Zhou, J.
2017-09-01
Traffic safety is a major concern in the transportation industry due to immense monetary and emotional burden caused by crashes of various severity levels, especially the injury and fatality ones. To reduce such crashes on all public roads, the safety management processes are commonly implemented which include network screening, problem diagnosis, countermeasure identification, and project prioritization. The selection of countermeasures for potential mitigation of crashes is governed by the influential factors which impact roadway crashes. Crash prediction model is the tool widely adopted by safety practitioners or researchers to link various influential factors to crash occurrences. Many different approaches have been used in the past studies to develop better fitting models which also exhibit prediction accuracy. In this study, a crash prediction model is developed to investigate the vehicular crashes occurring at roadway segments. The spatial and temporal nature of crash data is exploited to form a spatiotemporal model which accounts for the different types of heterogeneities among crash data and geometric or traffic flow variables. This study utilizes the Poisson lognormal model with random effects, which can accommodate the yearly variations in explanatory variables and the spatial correlations among segments. The dependency of different factors linked with roadway geometric, traffic flow, and road surface type on vehicular crashes occurring at segments was established as the width of lanes, posted speed limit, nature of pavement, and AADT were found to be correlated with vehicle crashes.
Elam, Kit K; Harold, Gordon T; Neiderhiser, Jenae M; Reiss, David; Shaw, Daniel S; Natsuaki, Misaki N; Gaysina, Darya; Barrett, Doug; Leve, Leslie D
2014-05-01
Socially disruptive behavior during peer interactions in early childhood is detrimental to children's social, emotional, and academic development. Few studies have investigated the developmental underpinnings of children's socially disruptive behavior using genetically sensitive research designs that allow examination of parent-on-child and child-on-parent (evocative genotype-environment correlation [rGE]) effects when examining family process and child outcome associations. Using an adoption-at-birth design, the present study controlled for passive genotype-environment correlation and directly examined evocative rGE while examining the associations between family processes and children's peer behavior. Specifically, the present study examined the evocative effect of genetic influences underlying toddler low social motivation on mother-child and father-child hostility and the subsequent influence of parent hostility on disruptive peer behavior during the preschool period. Participants were 316 linked triads of birth mothers, adoptive parents, and adopted children. Path analysis showed that birth mother low behavioral motivation predicted toddler low social motivation, which predicted both adoptive mother-child and father-child hostility, suggesting the presence of an evocative genotype-environment association. In addition, both mother-child and father-child hostility predicted children's later disruptive peer behavior. Results highlight the importance of considering genetically influenced child attributes on parental hostility that in turn links to later child social behavior. Implications for intervention programs focusing on early family processes and the precursors of disrupted child social development are discussed. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
Elam, Kit K.; Harold, Gordon T.; Neiderhiser, Jenae M.; Reiss, David; Shaw, Daniel S.; Natsuaki, Misaki N.; Gaysina, Darya; Barrett, Doug; Leve, Leslie D.
2014-01-01
Socially disruptive behavior during peer interactions in early childhood is detrimental to children’s social, emotional, and academic development. Few studies have investigated the developmental underpinnings of children’s socially disruptive behavior using genetically-sensitive research designs that allow examination of parent-on-child and child-on-parent (evocative genotype-environment correlation) effects when examining family process and child outcome associations. Using an adoption-at-birth design, the present study controlled for passive genotype-environment correlation and directly examined evocative genotype-environment correlation (rGE) while examining the associations between family processes and children’s peer behavior. Specifically, the present study examined the evocative effect of genetic influences underlying toddler low social motivation on mother-child and father-child hostility, and the subsequent influence of parent hostility on disruptive peer behavior during the preschool period. Participants were 316 linked triads of birth mothers, adoptive parents, and adopted children. Path analysis showed that birth mother low behavioral motivation predicted toddler low social motivation, which predicted both adoptive mother-child and father-child hostility, suggesting the presence of an evocative genotype-environment association. In addition, both mother-child and father-child hostility predicted children’s later disruptive peer behavior. Results highlight the importance of considering genetically-influenced child attributes on parental hostility that in turn link to later child social behavior. Implications for intervention programs focusing on early family processes and the precursors of disrupted child social development are discussed. PMID:24364829
Traffic congestion and reliability : linking solutions to problems.
DOT National Transportation Integrated Search
2004-07-19
The Traffic Congestion and Reliability: Linking Solutions to Problems Report provides : a snapshot of congestion in the United States by summarizing recent trends in : congestion, highlighting the role of unreliable travel times in the effects of con...
The link between drinking and gambling among undergraduate university students.
Hodgins, David C; Racicot, Stephanie
2013-09-01
The purpose of this research was to explore different aspects of the link between alcohol use and gambling among undergraduate university students (N = 121). Potential aspects of the link examined included level of involvement in each behavior, consequences, motives for involvement, and impaired control over involvement. Results confirmed that drinking and gambling among university students are associated, consistent with the expectations of a problem syndrome model. The strongest link was between general dimensions of problematic involvement for both behaviors. Students who drink to cope and have other indicators of alcohol problems are more likely to gamble to cope, gamble to win money, and have higher gambling involvement and gambling-related problems. However, the salience of drinking and gambling to cope in this relationship is an interesting finding that needs further exploration and extension to other problem behaviors. PsycINFO Database Record (c) 2013 APA, all rights reserved.
A constraint optimization based virtual network mapping method
NASA Astrophysics Data System (ADS)
Li, Xiaoling; Guo, Changguo; Wang, Huaimin; Li, Zhendong; Yang, Zhiwen
2013-03-01
Virtual network mapping problem, maps different virtual networks onto the substrate network is an extremely challenging work. This paper proposes a constraint optimization based mapping method for solving virtual network mapping problem. This method divides the problem into two phases, node mapping phase and link mapping phase, which are all NP-hard problems. Node mapping algorithm and link mapping algorithm are proposed for solving node mapping phase and link mapping phase, respectively. Node mapping algorithm adopts the thinking of greedy algorithm, mainly considers two factors, available resources which are supplied by the nodes and distance between the nodes. Link mapping algorithm is based on the result of node mapping phase, adopts the thinking of distributed constraint optimization method, which can guarantee to obtain the optimal mapping with the minimum network cost. Finally, simulation experiments are used to validate the method, and results show that the method performs very well.
Smyczynska, Joanna; Hilczer, Maciej; Smyczynska, Urszula; Stawerska, Renata; Tadeusiewicz, Ryszard; Lewinski, Andrzej
2015-01-01
The leading method for prediction of growth hormone (GH) therapy effectiveness are multiple linear regression (MLR) models. Best of our knowledge, we are the first to apply artificial neural networks (ANN) to solve this problem. For ANN there is no necessity to assume the functions linking independent and dependent variables. The aim of study is to compare ANN and MLR models of GH therapy effectiveness. Analysis comprised the data of 245 GH-deficient children (170 boys) treated with GH up to final height (FH). Independent variables included: patients' height, pre-treatment height velocity, chronological age, bone age, gender, pubertal status, parental heights, GH peak in 2 stimulation tests, IGF-I concentration. The output variable was FH. For testing dataset, MLR model predicted FH SDS with average error (RMSE) 0.64 SD, explaining 34.3% of its variability; ANN model derived on the same pre-processed data predicted FH SDS with RMSE 0.60 SD, explaining 42.0% of its variability; ANN model derived on raw data predicted FH with RMSE 3.9 cm (0.63 SD), explaining 78.7% of its variability. ANN seem to be valuable tool in prediction of GH treatment effectiveness, especially since they can be applied to raw clinical data.
RFI simulation definition study, exhibit D
NASA Technical Reports Server (NTRS)
Braun, W. R.
1981-01-01
Comparative analyses of experimental and predicted effects of the radio frequency interference (RFI) environment on the Shuttle/TDRSS S-band links were performed. Specifications are defined ad ESTL test requirements are presented. Procedures for using the RFI test generator in the ESTL S-band link tests are presented and performance predictions for these links in the RFI environment are provided.
Application of infrared thermography in computer aided diagnosis
NASA Astrophysics Data System (ADS)
Faust, Oliver; Rajendra Acharya, U.; Ng, E. Y. K.; Hong, Tan Jen; Yu, Wenwei
2014-09-01
The invention of thermography, in the 1950s, posed a formidable problem to the research community: What is the relationship between disease and heat radiation captured with Infrared (IR) cameras? The research community responded with a continuous effort to find this crucial relationship. This effort was aided by advances in processing techniques, improved sensitivity and spatial resolution of thermal sensors. However, despite this progress fundamental issues with this imaging modality still remain. The main problem is that the link between disease and heat radiation is complex and in many cases even non-linear. Furthermore, the change in heat radiation as well as the change in radiation pattern, which indicate disease, is minute. On a technical level, this poses high requirements on image capturing and processing. On a more abstract level, these problems lead to inter-observer variability and on an even more abstract level they lead to a lack of trust in this imaging modality. In this review, we adopt the position that these problems can only be solved through a strict application of scientific principles and objective performance assessment. Computing machinery is inherently objective; this helps us to apply scientific principles in a transparent way and to assess the performance results. As a consequence, we aim to promote thermography based Computer-Aided Diagnosis (CAD) systems. Another benefit of CAD systems comes from the fact that the diagnostic accuracy is linked to the capability of the computing machinery and, in general, computers become ever more potent. We predict that a pervasive application of computers and networking technology in medicine will help us to overcome the shortcomings of any single imaging modality and this will pave the way for integrated health care systems which maximize the quality of patient care.
Shared control on lunar spacecraft teleoperation rendezvous operations with large time delay
NASA Astrophysics Data System (ADS)
Ya-kun, Zhang; Hai-yang, Li; Rui-xue, Huang; Jiang-hui, Liu
2017-08-01
Teleoperation could be used in space on-orbit serving missions, such as object deorbits, spacecraft approaches, and automatic rendezvous and docking back-up systems. Teleoperation rendezvous and docking in lunar orbit may encounter bottlenecks for the inherent time delay in the communication link and the limited measurement accuracy of sensors. Moreover, human intervention is unsuitable in view of the partial communication coverage problem. To solve these problems, a shared control strategy for teleoperation rendezvous and docking is detailed. The control authority in lunar orbital maneuvers that involves two spacecraft as rendezvous and docking in the final phase was discussed in this paper. The predictive display model based on the relative dynamic equations is established to overcome the influence of the large time delay in communication link. We discuss and attempt to prove via consistent, ground-based simulations the relative merits of fully autonomous control mode (i.e., onboard computer-based), fully manual control (i.e., human-driven at the ground station) and shared control mode. The simulation experiments were conducted on the nine-degrees-of-freedom teleoperation rendezvous and docking simulation platform. Simulation results indicated that the shared control methods can overcome the influence of time delay effects. In addition, the docking success probability of shared control method was enhanced compared with automatic and manual modes.
Community violence concerns and adolescent sleep.
Bagley, Erika J; Tu, Kelly M; Buckhalt, Joseph A; El-Sheikh, Mona
2016-03-01
The goal of this study was to examine links between concerns about community violence and objective and subjective sleep parameters in an adolescent sample. Sex was considered as a moderator of effects. The study used a cross-sectional design. The community-based sample included 252 adolescents (53% girls) with an average age of 15.79 years (SD = 0.81) from the Southeastern United States. The sample included 34% African American and 66% European American adolescents from a wide range of socioeconomic backgrounds. Adolescent-reported community violence concerns were assessed using a composite of 3 separate subscales that measured perceived community safety and threats of community and school violence. Sleep duration and quality were assessed using actigraphy, and subjective sleep problems and daytime sleepiness were measured with subscales of the School Sleep Habits Survey. Community violence predicted lower sleep efficiency, more long-wake episodes, and more sleep/wake problems and sleepiness. Sex-related moderation effects revealed that girls in the sample were more vulnerable to the effects of violence concerns on their objective sleep quality. Findings highlight the role of community violence concerns on adolescents' sleep, revealing that greater community violence concerns are linked with lower levels of actigraphy-based and subjective reports of sleep quality, particularly for adolescent girls. Consideration of the mechanisms by which violence concerns may affect sleep is discussed.
NASA Astrophysics Data System (ADS)
Chardon, Jérémy; Hingray, Benoit; Favre, Anne-Catherine
2016-04-01
Scenarios of surface weather required for the impact studies have to be unbiased and adapted to the space and time scales of the considered hydro-systems. Hence, surface weather scenarios obtained from global climate models and/or numerical weather prediction models are not really appropriated. Outputs of these models have to be post-processed, which is often carried out thanks to Statistical Downscaling Methods (SDMs). Among those SDMs, approaches based on regression are often applied. For a given station, a regression link can be established between a set of large scale atmospheric predictors and the surface weather variable. These links are then used for the prediction of the latter. However, physical processes generating surface weather vary in time. This is well known for precipitation for instance. The most relevant predictors and the regression link are also likely to vary in time. A better prediction skill is thus classically obtained with a seasonal stratification of the data. Another strategy is to identify the most relevant predictor set and establish the regression link from dates that are similar - or analog - to the target date. In practice, these dates can be selected thanks to an analog model. In this study, we explore the possibility of improving the local performance of an analog model - where the analogy is applied to the geopotential heights 1000 and 500 hPa - using additional local scale predictors for the probabilistic prediction of the Safran precipitation over France. For each prediction day, the prediction is obtained from two GLM regression models - for both the occurrence and the quantity of precipitation - for which predictors and parameters are estimated from the analog dates. Firstly, the resulting combined model noticeably allows increasing the prediction performance by adapting the downscaling link for each prediction day. Secondly, the selected predictors for a given prediction depend on the large scale situation and on the considered region. Finally, even with such an adaptive predictor identification, the downscaling link appears to be robust: for a same prediction day, predictors selected for different locations of a given region are similar and the regression parameters are consistent within the region of interest.
Gambling Motives: Do They Explain Cognitive Distortions in Male Poker Gamblers?
Mathieu, Sasha; Barrault, Servane; Brunault, Paul; Varescon, Isabelle
2018-03-01
Gambling behavior is partly the result of varied motivations leading individuals to participate in gambling activities. Specific motivational profiles are found in gamblers, and gambling motives are closely linked to the development of cognitive distortions. This cross-sectional study aimed to predict cognitive distortions from gambling motives in poker players. The population was recruited in online gambling forums. Participants reported gambling at least once a week. Data included sociodemographic characteristics, the South Oaks Gambling Screen, the Gambling Motives Questionnaire-Financial and the Gambling-Related Cognition Scale. This study was conducted on 259 male poker gamblers (aged 18-69 years, 14.3% probable pathological gamblers). Univariate analyses showed that cognitive distortions were independently predicted by overall gambling motives (34.8%) and problem gambling (22.4%) (p < .05). The multivariate model, including these two variables, explained 39.7% of cognitive distortions (p < .05). The results associated with the literature data highlight that cognitive distortions are a good discriminating factor of gambling problems, showing a close inter-relationship between gambling motives, cognitive distortions and the severity of gambling. These data are consistent with the following theoretical process model: gambling motives lead individuals to practice and repeat the gambling experience, which may lead them to develop cognitive distortions, which in turn favor problem gambling. This study opens up new research perspectives to understand better the mechanisms underlying gambling practice and has clinical implications in terms of prevention and treatment. For example, a coupled motivational and cognitive intervention focused on gambling motives/cognitive distortions could be beneficial for individuals with gambling problems.
Grossi, Enzo
2006-05-03
In recent years a number of algorithms for cardiovascular risk assessment has been proposed to the medical community. These algorithms consider a number of variables and express their results as the percentage risk of developing a major fatal or non-fatal cardiovascular event in the following 10 to 20 years The author has identified three major pitfalls of these algorithms, linked to the limitation of the classical statistical approach in dealing with this kind of non linear and complex information. The pitfalls are the inability to capture the disease complexity, the inability to capture process dynamics, and the wide confidence interval of individual risk assessment. Artificial Intelligence tools can provide potential advantage in trying to overcome these limitations. The theoretical background and some application examples related to artificial neural networks and fuzzy logic have been reviewed and discussed. The use of predictive algorithms to assess individual absolute risk of cardiovascular future events is currently hampered by methodological and mathematical flaws. The use of newer approaches, such as fuzzy logic and artificial neural networks, linked to artificial intelligence, seems to better address both the challenge of increasing complexity resulting from a correlation between predisposing factors, data on the occurrence of cardiovascular events, and the prediction of future events on an individual level.
Developmental Pathways from Prenatal Tobacco and Stress Exposure to Behavioral Disinhibition
Clark, C.A.C.; Espy, K.A.; Wakschlag, L.
2016-01-01
Prenatal tobacco exposure (PTE) and prenatal stress exposure (PSE) each have been linked to externalizing behavior, although their effects generally have been considered in isolation. Here, we aimed to characterize the joint or interactive roles of PTE and PSE in early developmental pathways to behavioral disinhibition, a profile of cognitive and behavioral under-control that presages severe externalizing behavior. As part of a prospective, longitudinal study, 296 children were assessed at a mean age of 5 years. Exposures were assessed via repeated interviews across the prenatal period and bioassays of cotinine were obtained. Behavioral disinhibition was assessed using temperament measures in infancy, performance-based executive control tasks and measures of disruptive and inattentive behavior. PSE was associated with a higher probability of difficult temperament in infancy. Each exposure independently predicted poorer executive control at age 5 years. Difficult temperament and executive control difficulties in turn predicted elevated levels of disruptive behavior, although links from PTE and PSE to parent-reported attention problems were less robust. Children who experienced these prenatal exposures in conjunction with higher postnatal stress exposure showed the lowest executive control and highest levels of disruptive behavior. Findings highlight the compounding adverse impact of PTE and PSE on children’s behavioral trajectories. Given their high concordance, prenatal health campaigns should target these exposures in tandem. PMID:26628107
Cirrus microphysics and radiative transfer: Cloud field study on October 28, 1986
NASA Technical Reports Server (NTRS)
Kinne, Stefan; Ackerman, Thomas P.; Heymsfield, Andrew J.; Valero, Francisco P. J.; Sassen, Kenneth; Spinhirne, James D.
1990-01-01
The radiative properties of cirrus clouds present one of the unresolved problems in weather and climate research. Uncertainties in ice particle amount and size and, also, the general inability to model the single scattering properties of their usually complex particle shapes, prevent accurate model predictions. For an improved understanding of cirrus radiative effects, field experiments, as those of the Cirrus IFO of FIRE, are necessary. Simultaneous measurements of radiative fluxes and cirrus microphysics at multiple cirrus cloud altitudes allows the pitting of calculated versus measured vertical flux profiles; with the potential to judge current cirrus cloud modeling. Most of the problems in this study are linked to the inhomogeneity of the cloud field. Thus, only studies on more homogeneous cirrus cloud cases promises a possibility to improve current cirrus parameterizations. Still, the current inability to detect small ice particles will remain as a considerable handicap.
On different types of uncertainties in the context of the precautionary principle.
Aven, Terje
2011-10-01
Few policies for risk management have created more controversy than the precautionary principle. A main problem is the extreme number of different definitions and interpretations. Almost all definitions of the precautionary principle identify "scientific uncertainties" as the trigger or criterion for its invocation; however, the meaning of this concept is not clear. For applying the precautionary principle it is not sufficient that the threats or hazards are uncertain. A stronger requirement is needed. This article provides an in-depth analysis of this issue. We question how the scientific uncertainties are linked to the interpretation of the probability concept, expected values, the results from probabilistic risk assessments, the common distinction between aleatory uncertainties and epistemic uncertainties, and the problem of establishing an accurate prediction model (cause-effect relationship). A new classification structure is suggested to define what scientific uncertainties mean. © 2011 Society for Risk Analysis.
A Bayesian prediction model between a biomarker and the clinical endpoint for dichotomous variables.
Jiang, Zhiwei; Song, Yang; Shou, Qiong; Xia, Jielai; Wang, William
2014-12-20
Early biomarkers are helpful for predicting clinical endpoints and for evaluating efficacy in clinical trials even if the biomarker cannot replace clinical outcome as a surrogate. The building and evaluation of an association model between biomarkers and clinical outcomes are two equally important concerns regarding the prediction of clinical outcome. This paper is to address both issues in a Bayesian framework. A Bayesian meta-analytic approach is proposed to build a prediction model between the biomarker and clinical endpoint for dichotomous variables. Compared with other Bayesian methods, the proposed model only requires trial-level summary data of historical trials in model building. By using extensive simulations, we evaluate the link function and the application condition of the proposed Bayesian model under scenario (i) equal positive predictive value (PPV) and negative predictive value (NPV) and (ii) higher NPV and lower PPV. In the simulations, the patient-level data is generated to evaluate the meta-analytic model. PPV and NPV are employed to describe the patient-level relationship between the biomarker and the clinical outcome. The minimum number of historical trials to be included in building the model is also considered. It is seen from the simulations that the logit link function performs better than the odds and cloglog functions under both scenarios. PPV/NPV ≥0.5 for equal PPV and NPV, and PPV + NPV ≥1 for higher NPV and lower PPV are proposed in order to predict clinical outcome accurately and precisely when the proposed model is considered. Twenty historical trials are required to be included in model building when PPV and NPV are equal. For unequal PPV and NPV, the minimum number of historical trials for model building is proposed to be five. A hypothetical example shows an application of the proposed model in global drug development. The proposed Bayesian model is able to predict well the clinical endpoint from the observed biomarker data for dichotomous variables as long as the conditions are satisfied. It could be applied in drug development. But the practical problems in applications have to be studied in further research.
ERIC Educational Resources Information Center
Dussault, Frederic; Brendgen, Mara; Vitaro, Frank; Wanner, Brigitte; Tremblay, Richard E.
2011-01-01
Background: Research shows high co-morbidity between gambling problems and depressive symptoms, but the directionality of this link is unclear. Moreover, the co-occurrence of gambling problems and depressive symptoms could be spurious and explained by common underlying risk factors such as impulsivity and socio-family risk. The goals of the…
Boyes, Mark E; Bowes, Lucy; Cluver, Lucie D; Ward, Catherine L; Badcock, Nicholas A
2014-11-01
Bullying victimisation has been prospectively linked with mental health problems among children and adolescents in longitudinal studies in the developed world. However, research from the developing world, where adolescents face multiple risks to social and emotional development, has been limited by cross-sectional designs. This is the first longitudinal study of the psychological impacts of bullying victimisation in South Africa. The primary aim was to examine prospective relationships between bullying victimisation and internalising and externalising symptoms in South African youth. Secondary aims were to examine gender and age-related differences in experiences of bullying victimisation. Children and adolescents (10-17 years, 57 % female, n = 3,515) from high HIV-prevalent (>30 %) communities in South Africa were interviewed and followed-up 1 year later (97 % retention). Census enumeration areas were randomly selected from urban and rural sites in two provinces and door-to-door sampling included all households with a resident child/adolescent. Exposure to multiple experiences of bullying victimisation at baseline predicted internalising symptoms and conduct problems 1 year later. Additionally, baseline mental health scores predicted later bullying victimisation, demonstrating bi-directionality of relationships between bullying victimisation and mental health outcomes in this sample. Expected gender differences in physical, verbal, and relational bullying victimisation were evident and predicted declines in bullying victimisation over time were observed. In the developed world, school-based anti-bullying programmes have been shown to be effective in reducing bullying and victimisation. Anti-bullying programmes should be implemented and rigorously evaluated in South Africa, as this may promote improved mental health among South African children and adolescents.
Brains, brawn and sociality: a hyaena’s tale
Holekamp, Kay E.; Dantzer, Ben; Stricker, Gregory; Shaw Yoshida, Kathryn C.; Benson-Amram, Sarah
2015-01-01
Theoretically intelligence should evolve to help animals solve specific types of problems posed by the environment, but it remains unclear how environmental complexity or novelty facilitates the evolutionary enhancement of cognitive abilities, or whether domain-general intelligence can evolve in response to domain-specific selection pressures. The social complexity hypothesis, which posits that intelligence evolved to cope with the labile behaviour of conspecific group-mates, has been strongly supported by work on the sociocognitive abilities of primates and other animals. Here we review the remarkable convergence in social complexity between cercopithecine primates and spotted hyaenas, and describe our tests of predictions of the social complexity hypothesis in regard to both cognition and brain size in hyaenas. Behavioural data indicate that there has been remarkable convergence between primates and hyaenas with respect to their abilities in the domain of social cognition. Furthermore, within the family Hyaenidae, our data suggest that social complexity might have contributed to enlargement of the frontal cortex. However, social complexity failed to predict either brain volume or frontal cortex volume in a larger array of mammalian carnivores. To address the question of whether or not social complexity might be able to explain the evolution of domain-general intelligence as well as social cognition in particular, we presented simple puzzle boxes, baited with food and scaled to accommodate body size, to members of 39 carnivore species housed in zoos and found that species with larger brains relative to their body mass were more innovative and more successful at opening the boxes. However, social complexity failed to predict success in solving this problem. Overall our work suggests that, although social complexity enhances social cognition, there are no unambiguous causal links between social complexity and either brain size or performance in problem-solving tasks outside the social domain in mammalian carnivores. PMID:26160980
Anxiety Sensitivity and Cannabis Use-Related Problems: The Impact of Race
Dean, Kimberlye E.; Ecker, Anthony H.; Buckner, Julia D.
2017-01-01
Background and Objectives Cannabis is the most widely used illicit substance among young adults. Anxiety sensitivity (AS; i.e., fear of anxiety-related symptoms) is positively related to coping motives for cannabis use (which are robustly positively linked to cannabis-related problems). However, AS is unrelated to cannabis use-related problems. Yet, extant studies have been conducted on primarily White samples. It may be that among Black students, AS-physical concerns (i.e., fear of physical anxiety-related sensations) are related to cannabis problems given that Black individuals are more likely than White individuals to report experiencing greater and more intense somatic symptoms when experiencing anxiety. Black individuals may rely on cannabis to cope with fear of these somatic symptoms, continuing to use despite cannabis-related problems. Methods The current study tested whether race moderated the relation between AS-physical concerns and cannabis problems among 102 (85.3% female) current cannabis using undergraduates who were either non-Hispanic Black (n= 51) or non-Hispanic White (n= 51). Results After controlling for frequency of cannabis use, income, and gender, race significantly moderated the relation between AS-physical concerns and cannabis use-related problems such that AS-physical concerns significantly predicted cannabis-related problems among Black and not White individuals. Discussion and Conclusions Findings highlight the importance of considering race in identifying psychosocial predictors of cannabis-related problems. Scientific Significance Intervention strategies for Black cannabis users may benefit from examining and targeting AS-physical concerns. PMID:28295843
Anxiety sensitivity and cannabis use-related problems: The impact of race.
Dean, Kimberlye E; Ecker, Anthony H; Buckner, Julia D
2017-04-01
Cannabis is the most widely used illicit substance among young adults. Anxiety sensitivity (AS; ie, fear of anxiety-related symptoms) is positively related to coping motives for cannabis use (which are robustly positively linked to cannabis-related problems). However, AS is unrelated to cannabis use-related problems. Yet, extant studies have been conducted on primarily White samples. It may be that among Black students, AS-physical concerns (ie, fear of physical anxiety-related sensations) are related to cannabis problems given that Black individuals are more likely than White individuals to report experiencing greater and more intense somatic symptoms when experiencing anxiety. Black individuals may rely on cannabis to cope with fear of these somatic symptoms, continuing to use despite cannabis-related problems. The current study tested whether race moderated the relation between AS-physical concerns and cannabis problems among 102 (85.3% female) current cannabis using undergraduates who were either non-Hispanic Black (n = 51) or non-Hispanic White (n = 51). After controlling for frequency of cannabis use, income, and gender, race significantly moderated the relation between AS-physical concerns and cannabis use-related problems such that AS-physical concerns significantly predicted cannabis-related problems among Black and not White individuals. Findings highlight the importance of considering race in identifying psychosocial predictors of cannabis-related problems. Intervention strategies for Black cannabis users may benefit from examining and targeting AS-physical concerns. (Am J Addict 2017;26:209-214). © 2017 American Academy of Addiction Psychiatry.
Waller, Rebecca; Hyde, Luke W; Baskin-Sommers, Arielle R; Olson, Sheryl L
2017-04-01
Callous unemotional (CU) behaviors are linked to aggression, behavior problems, and difficulties in peer relationships in children and adolescents. However, few studies have examined whether early childhood CU behaviors predict aggression or peer-rejection during late-childhood or potential moderation of this relationship by executive function. The current study examined whether the interaction of CU behaviors and executive function in early childhood predicted different forms of aggression in late-childhood, including proactive, reactive, and relational aggression, as well as how much children were liked by their peers. Data from cross-informant reports and multiple observational tasks were collected from a high-risk sample (N = 240; female = 118) at ages 3 and 10 years old. Parent reports of CU behaviors at age 3 predicted teacher reports of reactive, proactive, and relational aggression, as well as lower peer-liking at age 10. Moderation analysis showed that specifically at high levels of CU behaviors and low levels of observed executive function, children were reported by teachers as showing greater reactive and proactive aggression, and were less-liked by peers. Findings demonstrate that early childhood CU behaviors and executive function have unique main and interactive effects on both later aggression and lower peer-liking even when taking into account stability in behavior problems over time. By elucidating how CU behaviors and deficits in executive function potentiate each other during early childhood, we can better characterize the emergence of severe and persistent behavior and interpersonal difficulties across development.
Kerr, D C R; Capaldi, D M
2011-04-01
Longitudinal research supports that suicidal thoughts and behaviors in adolescence predict maladjustment in young adulthood. Prior research supports links between suicide attempt and aggression, perhaps because of a propensity for impulsive behavior in states of high negative affect that underlies both problems. Such vulnerability may increase risk for intimate partner violence and generally poor young adulthood relational adjustment. A total of 153 men participated in annual assessments from ages 10-32 years and with a romantic partner at three assessments from ages 18-25 years. Multi-method/multi-informant constructs were formed for parent/family risk factors, adolescent psychopathology (e.g. suicide-attempt history, mother-, father-, teacher- and self-reported physical aggression) and young adulthood relational distress (jealousy and low relationship satisfaction) and maladaptive relationship behavior (observed, self- and partner-reported physical and psychological aggression toward a partner, partner-reported injury, official domestic violence arrest records and relationship instability). Across informants, adolescent aggression was correlated with suicide-attempt history. With few exceptions, aggression and a suicide attempt in adolescence each predicted negative romantic relationship outcomes after controlling for measured confounds. Adolescent aggression predicted young adulthood aggression toward a partner, in part, via relationship dissatisfaction. Boys' aggression and suicide-attempt history in adolescence each predict poor relationship outcomes, including partner violence, in young adulthood. Findings are consistent with the theory of a trait-like vulnerability, such as impulsive aggression, that undermines adaptation across multiple domains in adolescence and young adulthood. Prevention and intervention approaches can target common causes of diverse public health problems.
Kerr, David C. R.; Capaldi, Deborah M.
2010-01-01
Background Longitudinal research supports that suicidal thoughts and behaviors in adolescence predict maladjustment in young adulthood. Prior research supports links between suicide attempt and aggression, perhaps because of a propensity for impulsive behavior in states of high negative affect that underlies both problems. Such vulnerability may increase risk for intimate partner violence and generally poor young adulthood relational adjustment. Method 153 men participated in annual assessments from ages 10 to 32 years and with a romantic partner at three assessments from ages 18 to 25 years. Multimethod/multi-informant constructs were formed for parent/family risk factors, adolescent psychopathology (e.g., suicide attempt history; mother-, father-, teacher-, and self-reported physical aggression), and young adulthood relational distress (jealousy and low relationship satisfaction) and maladaptive relationship behavior (observed, self-, and partner-reported physical and psychological aggression toward a partner, partner-reported injury, official domestic violence arrest records, and relationship instability). Results Across informants, adolescent aggression was correlated with suicide attempt history. With few exceptions, aggression and a suicide attempt in adolescence each predicted negative romantic relationship outcomes after controlling for measured confounds. Adolescent aggression predicted young adulthood aggression toward a partner, in part, via relationship dissatisfaction. Conclusions Boys’ aggression and suicide attempt history in adolescence each predict poor relationship outcomes, including partner violence, in young adulthood. Findings are consistent with the theory of a trait-like vulnerability, such as impulsive aggression, that undermines adaptation across multiple domains in adolescence and young adulthood. Prevention and intervention approaches can target common causes of diverse public health problems. PMID:20540815
Merrill, Jennifer E.; Wardell, Jeffrey D.; Read, Jennifer P.
2014-01-01
Objective: Although college students experience a diverse range of alcohol consequences, most studies focus on global, rather than distinct, consequence types. One predictor of unique consequences—drinking motives—has been studied only cross-sectionally. We aimed to examine the prediction of unique alcohol consequence domains (social/interpersonal, academic/occupational, risky behavior, impaired control, poor self-care, diminished self-perception, blackout drinking, and physiological dependence) by coping and enhancement motives over the course of one year. We hypothesized that coping motives would directly predict and that enhancement motives would indirectly (through alcohol use) predict unique consequences. Method: Web surveys were administered to a sample of college students (n = 552, 62% female) at the beginning of the fall semester for 2 consecutive academic years. Structural equation modeling was used to test direct and indirect paths from motives to consequences. Results: The data supported hypothesized direct, prospective paths from coping motives to several alcohol consequences (impaired control, diminished self-perception, poor self-care, risky behaviors, academic/occupational, and physiological dependence). These associations were not mediated by alcohol consumption. Enhancement motives were indirectly associated with all eight consequence domains by way of increased alcohol use at follow-up. Models were invariant across gender, year in school, and symptoms of posttraumatic stress. Conclusions: Findings suggest that whether motives act as a final common pathway to problem drinking may depend on which motives and which drinking outcomes are examined. As coping motives demonstrate a direct link to unique alcohol problem types over time, individuals endorsing these motives may need to be prioritized for intervention. PMID:24411801
Vasconcelos E Sa, Debora; Barrowclough, Christine; Hartley, Samantha; Wearden, Alison
2017-06-01
There is evidence that self-blame is an important predictor of distress and depression in relatives of people with long-term psychosis, but there is limited research investigating the nature and correlates of self-blame in relatives of people with recent-onset psychosis. Self-blame motivates a tendency to engage with others and to repair wrongdoings; it might be that such cognitions also impact on relatives' behaviours towards the patient. This study examined the association between self-blame and psychological distress, and tested the prediction that greater self-blame would be associated with more behavioural control attempts to patients in a sample of relatives of people with recent-onset psychosis. Statements pertaining to self-blame and behavioural control were extracted and rated from 80 interviews with relatives, who also completed the General Health Questionnaire-28. Content analysis was used to examine the nature of self-blame attributions. Regression analyses were used to explore the links between self-blame attributions and distress, and between self-blame and behavioural control in this recent-onset population. Higher levels of self-blame were associated with more behavioural control attempts, and self-blame predicted relatives' behavioural responses when adjusting for the contribution of control attributions. Self-blame was also linked with distress, but did not emerge as an independent predictor in multivariate analysis. Most relatives who blamed themselves did so for not overseeing their family member's mental health problems properly or for perceiving themselves generally as poor carers. This study extends findings related to self-blame to a population of relatives of people with recent-onset psychosis and highlights the possible role of blaming cognitions in promoting interpersonal engagement through behavioural control. Self-blaming beliefs were linked with increased distress in relatives of people with recent-onset psychosis; Increased self-blame was associated with more behavioural control attempts; Most relatives blamed themselves for not overseeing their family member's mental health problems properly, and for perceiving themselves generally as poor carers. The cross-sectional study design limits inferences about causality. © 2017 The British Psychological Society.
Multicast backup reprovisioning problem for Hamiltonian cycle-based protection on WDM networks
NASA Astrophysics Data System (ADS)
Din, Der-Rong; Huang, Jen-Shen
2014-03-01
As networks grow in size and complexity, the chance and the impact of failures increase dramatically. The pre-allocated backup resources cannot provide 100% protection guarantee when continuous failures occur in a network. In this paper, the multicast backup re-provisioning problem (MBRP) for Hamiltonian cycle (HC)-based protection on WDM networks for the link-failure case is studied. We focus on how to recover the protecting capabilities of Hamiltonian cycle against the subsequent link-failures on WDM networks for multicast transmissions, after recovering the multicast trees affected by the previous link-failure. Since this problem is a hard problem, an algorithm, which consists of several heuristics and a genetic algorithm (GA), is proposed to solve it. The simulation results of the proposed method are also given. Experimental results indicate that the proposed algorithm can solve this problem efficiently.
Compression in Working Memory and Its Relationship With Fluid Intelligence.
Chekaf, Mustapha; Gauvrit, Nicolas; Guida, Alessandro; Mathy, Fabien
2018-06-01
Working memory has been shown to be strongly related to fluid intelligence; however, our goal is to shed further light on the process of information compression in working memory as a determining factor of fluid intelligence. Our main hypothesis was that compression in working memory is an excellent indicator for studying the relationship between working-memory capacity and fluid intelligence because both depend on the optimization of storage capacity. Compressibility of memoranda was estimated using an algorithmic complexity metric. The results showed that compressibility can be used to predict working-memory performance and that fluid intelligence is well predicted by the ability to compress information. We conclude that the ability to compress information in working memory is the reason why both manipulation and retention of information are linked to intelligence. This result offers a new concept of intelligence based on the idea that compression and intelligence are equivalent problems. Copyright © 2018 Cognitive Science Society, Inc.
Predicting Flavonoid UGT Regioselectivity
Jackson, Rhydon; Knisley, Debra; McIntosh, Cecilia; Pfeiffer, Phillip
2011-01-01
Machine learning was applied to a challenging and biologically significant protein classification problem: the prediction of avonoid UGT acceptor regioselectivity from primary sequence. Novel indices characterizing graphical models of residues were proposed and found to be widely distributed among existing amino acid indices and to cluster residues appropriately. UGT subsequences biochemically linked to regioselectivity were modeled as sets of index sequences. Several learning techniques incorporating these UGT models were compared with classifications based on standard sequence alignment scores. These techniques included an application of time series distance functions to protein classification. Time series distances defined on the index sequences were used in nearest neighbor and support vector machine classifiers. Additionally, Bayesian neural network classifiers were applied to the index sequences. The experiments identified improvements over the nearest neighbor and support vector machine classifications relying on standard alignment similarity scores, as well as strong correlations between specific subsequences and regioselectivities. PMID:21747849
What causes similarity in catchments?
NASA Astrophysics Data System (ADS)
Savenije, Hubert
2014-05-01
One of the biggest issues in hydrology is how to handle the heterogeneity of catchment properties at different scales. But is this really such a big issue? Is this problem not merely the consequence of how we conceptualise and how we model catchments? Is there not far more similarity than we observe. Maybe we are not looking at the right things or at the right scale to see the similarity. The identity of catchments is largely determined by: the landscape, the ecosystem living on the landscape, and the geology, in that order. Soils, which are often seen as a crucial aspect of hydrological behaviour, are far less important, as will be demonstrated. The main determinants of hydrological behaviour are: the landscape composition, the rooting depth and the phenology. These determinants are a consequence of landscape and ecosystem evolution, which, in turn, are the manifestations of entropy production. There are striking similarities between catchments. The different runoff processes from hillslopes are linked and similar in different environments (McDonnell, 2013). Wetlands behave similarly all over the world. The key is to classify landscapes and to link the ecosystems living on them to climate. The ecosystem then is the main controller of hydrological behaviour. Besides phenology, the rooting depth is key in determining runoff behaviour. Both are strongly linked to climate and much less to soil properties. An example is given of how rooting depth is determined by climate, and how rooting depth can be predicted without calibration, providing a strong constraints on the prediction of rainfall partitioning and catchment runoff.
Temperament and Parenting during the First Year of Life Predict Future Child Conduct Problems
Lahey, Benjamin B.; Van Hulle, Carol A.; Keenan, Kate; Rathouz, Paul J.; D’Onofrio, Brian M.; Rodgers, Joseph Lee; Waldman, Irwin D.
2010-01-01
Predictive associations between parenting and temperament during the first year of life and child conduct problems were assessed longitudinally in 1,863 offspring of a representative sample of women. Maternal ratings of infant fussiness, activity level, predictability, and positive affect each independently predicted maternal ratings of conduct problems during ages 4–13 years. Furthermore, a significant interaction indicated that infants who were both low in fussiness and high in predictability were at very low risk for future conduct problems. Fussiness was a stronger predictor of conduct problems in boys whereas fearfulness was a stronger predictor in girls. Conduct problems also were robustly predicted by low levels of early mother-report cognitive stimulation. Interviewer-rated maternal responsiveness was a robust predictor of conduct problems, but only among infants low in fearfulness. Spanking during infancy predicted slightly more severe conduct problems, but the prediction was moderated by infant fussiness and positive affect. Thus, individual differences in risk for mother-rated conduct problems across childhood are already partly evident in maternal ratings of temperament during the first year of life and are predicted by early parenting and parenting-by-temperament interactions. PMID:18568397
NASA Astrophysics Data System (ADS)
Liou, Meng-Sing
2013-11-01
The development of computational fluid dynamics over the last few decades has yielded enormous successes and capabilities that are being routinely employed today; however there remain some open problems to be properly resolved. One example is the so-called overheating problem, which can arise in two very different scenarios, from either colliding or receding streams. Common in both is a localized, numerically over-predicted temperature. Von Neumann reported the former, a compressive overheating, nearly 70 years ago and numerically smeared the temperature peak by introducing artificial diffusion. However, the latter is unphysical in an expansive (rarefying) situation; it still dogs every method known to the author. We will present a study aiming at resolving this overheating problem and we find that: (1) the entropy increase is one-to-one linked to the increase in the temperature rise and (2) the overheating is inevitable in the current computational fluid dynamics framework in practice. Finally we will show a simple hybrid method that fundamentally cures the overheating problem in a rarefying flow, but also retains the property of accurate shock capturing. Moreover, this remedy (enhancement of current numerical methods) can be included easily in the present Eulerian codes. This work is performed under NASA's Fundamental Aeronautics Program.
Arnett, Anne B; Pennington, Bruce F; Young, Jami F; Hankin, Benjamin L
2016-04-01
The onset of hyperactivity/impulsivity and attention problems (HAP) is typically younger than that of conduct problems (CP), and some research supports a directional relation wherein HAP precedes CP. Studies have tested this theory using between-person and between-group comparisons, with conflicting results. In contrast, prior research has not examined the effects of within-person fluctuations in HAP on CP. This study tested the hypothesis that within-person variation in HAP would positively predict subsequent within-person variation in CP, in two population samples of youth (N = 620) who participated in identical methods of assessment over the course of 30 months. Three-level, hierarchical models were used to test for within-person, longitudinal associations between HAP and CP, as well as moderating effects of between-person and between-family demographics. We found a small but significant association in the expected direction for older youth, but the opposite effect in younger and non-Caucasian youth. These results were replicated across both samples. The process by which early HAP relates to later CP may vary by age and racial identity. © 2015 Association for Child and Adolescent Mental Health.
Lewis, Robin J.; Mason, Tyler B.; Winstead, Barbara A.; Kelley, Michelle L.
2015-01-01
Objective This study proposed and tested the first conceptual model of sexual minority specific (discrimination, internalized homophobia) and more general risk factors (perpetrator and partner alcohol use, anger, relationship satisfaction) for intimate partner violence among partnered lesbian women. Method Self-identified lesbian women (N=1048) were recruited from online market research panels. Participants completed an online survey that included measures of minority stress, anger, alcohol use and alcohol-related problems, relationship satisfaction, psychological aggression, and physical violence. Results The model demonstrated good fit and significant links from sexual minority discrimination to internalized homophobia and anger, from internalized homophobia to anger and alcohol problems, and from alcohol problems to intimate partner violence. Partner alcohol use predicted partner physical violence. Relationship dissatisfaction was associated with physical violence via psychological aggression. Physical violence was bidirectional. Conclusions Minority stress, anger, alcohol use and alcohol-related problems play an important role in perpetration of psychological aggression and physical violence in lesbian women's intimate partner relationships. The results of this study provide evidence of potentially modifiable sexual minority specific and more general risk factors for lesbian women's partner violence. PMID:28239508
van der Molen, Elsa; Blokland, Arjan A J; Hipwell, Alison E; Vermeiren, Robert R J M; Doreleijers, Theo A H; Loeber, Rolf
2015-07-01
It is widely recognized that early onset of disruptive behavior is linked to a variety of detrimental outcomes in males, later in life. In contrast, little is known about the association between girls' childhood trajectories of disruptive behavior and adjustment problems in early adolescence. This study used nine waves of data from the ongoing Pittsburgh Girls Study. A semiparametric group-based model was used to identify trajectories of disruptive behavior in 1,513 girls from age 6 to 12 years. Adjustment problems were characterized by depression, self-harm, Post Traumatic Stress Disorder (PTSD), substance use, interpersonal aggression, sexual behavior, affiliation with delinquent peers, and academic achievement at ages 13 and 14. Three trajectories of childhood disruptive behavior were identified: low, medium, and high. Girls in the high group were at increased risk for depression, self-harm, PTSD, illegal substance use, interpersonal aggression, early and risky sexual behavior, and lower academic achievement. The likelihood of multiple adjustment problems increased with trajectories reflecting higher levels of disruptive behavior. Girls following the high childhood trajectory of disruptive behavior require early intervention programs to prevent multiple, adverse outcomes in adolescence and further escalation in adulthood. © 2014 Association for Child and Adolescent Mental Health.
van der Molen, Elsa; Blokland, Arjan A. J.; Hipwell, Alison E.; Vermeiren, Robert R.J.M.; Doreleijers, Theo A.H.; Loeber, Rolf
2014-01-01
Background It is widely recognized that early onset of disruptive behavior is linked to a variety of detrimental outcomes in males later in life. In contrast, little is known about the association between girls’ childhood trajectories of disruptive behavior and adjustment problems in early adolescence. Methods The current study used 9 waves of data from the ongoing Pittsburgh Girls Study. A semi-parametric group based model was used to identify trajectories of disruptive behavior in 1,513 girls from age 6 to 12 years. Adjustment problems were characterized by depression, self-harm, PTSD, substance use, interpersonal aggression, sexual behavior, affiliation with delinquent peers, and academic achievement at ages 13 and 14. Results Three trajectories of childhood disruptive behavior were identified: low, medium, and high. Girls in the high group were at increased risk for depression, self-harm, PTSD, illegal substance use, interpersonal aggression, early and risky sexual behavior, and lower academic achievement. The likelihood of multiple adjustment problems increased with trajectories reflecting higher levels of disruptive behavior. Conclusion Girls following the high childhood trajectory of disruptive behavior require early intervention programs to prevent multiple, adverse outcomes in adolescence and further escalation in adulthood. PMID:25302849
Childhood Problem Behaviors and Death by Midlife: The British National Child Development Study
ERIC Educational Resources Information Center
Jokela, Markus; Ferrie, Jane; Kivimaki, Mika
2009-01-01
The childhood behavior problem as assessed by teachers of over 11,000 boys and girls who were born in 1958 and were part of the British National Child Development Study is reviewed to determine a link between these behaviors and mortality by the age of 46. It is found that childhood behavior problem is linked to long-term mortality beyond…
Perren, Sonja; Ettekal, Idean; Ladd, Gary
2013-01-01
Evidence indicates that being a victim of bullying or peer aggression has negative short- and long-term consequences. In this study, we investigated the mediating and moderating role of two types of attributional mechanisms (hostile and self-blaming attributions) on children's maladjustment (externalizing and internalizing problems). In total, 478 children participated in this longitudinal study from grade 5 to grade 7. Children, parents, and teachers repeatedly completed questionnaires. Peer victimization was assessed through peer reports (T1). Attributions were assessed through self-reports using hypothetical scenarios (T2). Parents and teachers reported on children's maladjustment (T1 and T3). Peer victimization predicted increases in externalizing and internalizing problems. Hostile attributions partially mediated the impact of victimization on increases in externalizing problems. Self-blame was not associated with peer victimization. However, for children with higher levels of self-blaming attributions, peer victimization was linked more strongly with increases in internalizing problems. Results imply that hostile attributions may operate as a potential mechanism through which negative experiences with peers lead to increases in children's aggressive and delinquent behavior, whereas self-blame exacerbates victimization's effects on internalizing problems. © 2012 The Authors. Journal of Child Psychology and Psychiatry © 2012 Association for Child and Adolescent Mental Health.
Evans, Chris D; Cooper, David M; Juggins, Steve; Jenkins, Alan; Norris, Dave
2006-07-15
Freshwater sensitivity to acidification varies according to geology, soils and land-use, and consequently it remains difficult to quantify the current extent of acidification, or its biological impacts, based on limited spot samples. The problem is particularly acute for river systems, where the transition from acid to circum-neutral conditions can occur within short distances. This paper links an established point-based long-term acidification model (MAGIC) with a landscape-based mixing model (PEARLS) to simulate spatial and temporal variations in acidification for a 256 km(2) catchment in North Wales. Empirical relationships are used to predict changes in the probability of occurrence of an indicator invertebrate species, Baetis rhodani, across the catchment as a function of changing chemical status. Results suggest that, at present, 27% of the river network has a mean acid neutralising capacity (ANC) below a biologically-relevant threshold of 20 microeq l(-1). At high flows, this proportion increases to 45%. The model suggests that only around 16% of the stream network had a mean ANC < 20 microeq l(-1) in 1850, but that this increased to 42% at the sulphur deposition peak around 1970. By 2050 recovery is predicted, but with some persistence of acid conditions in the most sensitive, peaty headwaters. Stream chemical suitability for Baetis rhodani is also expected to increase in formerly acidified areas, but for overall abundance to remain below that simulated in 1850. The approach of linking plot-scale process-based models to catchment mixing models provides a potential means of predicting the past and future spatial extent of acidification within large, heterogeneous river networks and regions. Further development of ecological response models to include other chemical predictor variables and the effects of acid episodes would allow more realistic simulation of the temporal and spatial dynamics of ecosystem recovery from acidification.
Model updating in flexible-link multibody systems
NASA Astrophysics Data System (ADS)
Belotti, R.; Caneva, G.; Palomba, I.; Richiedei, D.; Trevisani, A.
2016-09-01
The dynamic response of flexible-link multibody systems (FLMSs) can be predicted through nonlinear models based on finite elements, to describe the coupling between rigid- body and elastic behaviour. Their accuracy should be as high as possible to synthesize controllers and observers. Model updating based on experimental measurements is hence necessary. By taking advantage of the experimental modal analysis, this work proposes a model updating procedure for FLMSs and applies it experimentally to a planar robot. Indeed, several peculiarities of the model of FLMS should be carefully tackled. On the one hand, nonlinear models of a FLMS should be linearized about static equilibrium configurations. On the other, the experimental mode shapes should be corrected to be consistent with the elastic displacements represented in the model, which are defined with respect to a fictitious moving reference (the equivalent rigid link system). Then, since rotational degrees of freedom are also represented in the model, interpolation of the experimental data should be performed to match the model displacement vector. Model updating has been finally cast as an optimization problem in the presence of bounds on the feasible values, by also adopting methods to improve the numerical conditioning and to compute meaningful updated inertial and elastic parameters.
Estimating topological properties of weighted networks from limited information
NASA Astrophysics Data System (ADS)
Gabrielli, Andrea; Cimini, Giulio; Garlaschelli, Diego; Squartini, Angelo
A typical problem met when studying complex systems is the limited information available on their topology, which hinders our understanding of their structural and dynamical properties. A paramount example is provided by financial networks, whose data are privacy protected. Yet, the estimation of systemic risk strongly depends on the detailed structure of the interbank network. The resulting challenge is that of using aggregate information to statistically reconstruct a network and correctly predict its higher-order properties. Standard approaches either generate unrealistically dense networks, or fail to reproduce the observed topology by assigning homogeneous link weights. Here we develop a reconstruction method, based on statistical mechanics concepts, that exploits the empirical link density in a highly non-trivial way. Technically, our approach consists in the preliminary estimation of node degrees from empirical node strengths and link density, followed by a maximum-entropy inference based on a combination of empirical strengths and estimated degrees. Our method is successfully tested on the international trade network and the interbank money market, and represents a valuable tool for gaining insights on privacy-protected or partially accessible systems. Acknoweledgement to ``Growthcom'' ICT - EC project (Grant No: 611272) and ``Crisislab'' Italian Project.
Similarity-based Regularized Latent Feature Model for Link Prediction in Bipartite Networks.
Wang, Wenjun; Chen, Xue; Jiao, Pengfei; Jin, Di
2017-12-05
Link prediction is an attractive research topic in the field of data mining and has significant applications in improving performance of recommendation system and exploring evolving mechanisms of the complex networks. A variety of complex systems in real world should be abstractly represented as bipartite networks, in which there are two types of nodes and no links connect nodes of the same type. In this paper, we propose a framework for link prediction in bipartite networks by combining the similarity based structure and the latent feature model from a new perspective. The framework is called Similarity Regularized Nonnegative Matrix Factorization (SRNMF), which explicitly takes the local characteristics into consideration and encodes the geometrical information of the networks by constructing a similarity based matrix. We also develop an iterative scheme to solve the objective function based on gradient descent. Extensive experiments on a variety of real world bipartite networks show that the proposed framework of link prediction has a more competitive, preferable and stable performance in comparison with the state-of-art methods.
Eriksonian intimacy development, relationship satisfaction, and depression in gay male couples
Starks, Tyrel J.; Doyle, Kendell M.; Millar, Brett M.; Parsons, Jeffrey T.
2017-01-01
Research suggests connections or links between the mental health of both partners in a romantic relationship, as partners often report similar mental health problems, with implications for relationship functioning. The current study utilized the framework of interdependence theory to explore associations among intimacy development, as conceptualized by Erikson, relationship satisfaction, and depression in a sample of 128 same-sex male couples. In each couple, one partner was recruited first through active or passive outreach conducted online and in-person, and after completion of the online survey, was then invited to send his partner a link to the study. The 256 male respondents (mean age = 32.6 years) all reported a U.S. residence and had an average relationship length of five years. Utilizing the Actor-Partner Interdependence Model, analyses indicated that participants’ intimacy development directly predicted their own relationship satisfaction (B = 1.84, p< .01) as well as their partner’s relationship satisfaction (B = 1.61, p<.01). Similarly, both the actor (B = -0.04, p< .01) and partner (B = -0.04, p< .05) effects of relationship satisfaction on depression were significant. Consistent with the interdependent concept of joint control, three indirect pathways linked Eriksonian intimacy to depression through relationship satisfaction. These findings suggest that individual development may become linked to mental health through pathways involving dyadic functioning. This pattern implies highly inter-connected links between the intra-personal and inter-personal, which have implications for mental health intervention with gay men in relationships. PMID:29805985
Conditions for Viral Influence Spreading through Multiplex Correlated Social Networks
NASA Astrophysics Data System (ADS)
Hu, Yanqing; Havlin, Shlomo; Makse, Hernán A.
2014-04-01
A fundamental problem in network science is to predict how certain individuals are able to initiate new networks to spring up "new ideas." Frequently, these changes in trends are triggered by a few innovators who rapidly impose their ideas through "viral" influence spreading, producing cascades of followers and fragmenting an old network to create a new one. Typical examples include the rise of scientific ideas or abrupt changes in social media, like the rise of Facebook to the detriment of Myspace. How this process arises in practice has not been conclusively demonstrated. Here, we show that a condition for sustaining a viral spreading process is the existence of a multiplex-correlated graph with hidden "influence links." Analytical solutions predict percolation-phase transitions, either abrupt or continuous, where networks are disintegrated through viral cascades of followers, as in empirical data. Our modeling predicts the strict conditions to sustain a large viral spreading via a scaling form of the local correlation function between multilayers, which we also confirm empirically. Ultimately, the theory predicts the conditions for viral cascading in a large class of multiplex networks ranging from social to financial systems and markets.
Amphetamine primes motivation to gamble and gambling-related semantic networks in problem gamblers.
Zack, Martin; Poulos, Constantine X
2004-01-01
Previous research suggests that gambling can induce effects that closely resemble a psychostimulant drug effect. Modest doses of addictive drugs can prime motivation for drugs with similar properties. Together, these findings imply that a dose of a psychostimulant drug could prime motivation to gamble in problem gamblers. This study assessed priming effects of oral D-amphetamine (AMPH) (30 mg) in a within-subject, counter-balanced, placebo-controlled design in problem gamblers (n=10), comorbid gamblerdrinkers (n=6), problem drinkers (n=8), and healthy controls (n=12). Modified visual analog scales assessed addictive motivation and subjective effects. A modified rapid reading task assessed pharmacological activation of words from motivationally relevant and irrelevant semantic domains (Gambling, Alcohol, Positive Affect, Negative Affect, Neutral). AMPH increased self-reported motivation for gambling in problem gamblers. Severity of problem gambling predicted positive subjective effects of AMPH and motivation to gamble under the drug. There was little evidence that AMPH directly primed motivation for alcohol in problem drinkers. On the reading task, AMPH produced undifferentiated improvement in reading speed to all word classes in Nongamblers. By contrast, in the two problem gambler groups, AMPH improved reading speed to Gambling words while profoundly slowing reading speed to motivationally irrelevant Neutral words. The latter finding was interpreted as directly congruent with models, which contend that priming of addictive motivation involves a linked suppression of motivationally irrelevant stimuli. This study provides experimental evidence that psychostimulant-like neurochemical activation is an important component of gambling addiction.
Vanderveen, Keith B [Tracy, CA; Talbot, Edward B [Livermore, CA; Mayer, Laurence E [Davis, CA
2008-04-08
Nodes in a network having a plurality of nodes establish communication links with other nodes using available transmission media, as the ability to establish such links becomes available and desirable. The nodes predict when existing communications links will fail, become overloaded or otherwise degrade network effectiveness and act to establish substitute or additional links before the node's ability to communicate with the other nodes on the network is adversely affected. A node stores network topology information and programmed link establishment rules and criteria. The node evaluates characteristics that predict existing links with other nodes becoming unavailable or degraded. The node then determines whether it can form a communication link with a substitute node, in order to maintain connectivity with the network. When changing its communication links, a node broadcasts that information to the network. Other nodes update their stored topology information and consider the updated topology when establishing new communications links for themselves.
Dynamics of Pure Shape, Relativity, and the Problem of Time
NASA Astrophysics Data System (ADS)
Barbour, Julian
A new approach to the dynamics of the universe based on work by Ó Murchadha, Foster, Anderson and the author is presented. The only kinematics presupposed is the spatial geometry needed to define configuration spaces in purely relational terms. A new formulation of the relativity principle based on Poincarés analysis of the problem of absolute and relative motion (Machs principle) is given. The entire dynamics is based on shape and nothing else. It leads to much stronger predictions than standard Newtonian theory. For the dynamics of Riemannian 3-geometries on which matter fields also evolve, implementation of the new relativity principle establishes unexpected links between special relativity, general relativity and the gauge principle. They all emerge together as a self-consistent complex from a unified and completely relational approach to dynamics. A connection between time and scale invariance is established. In particular, the representation of general relativity as evolution of the shape of space leads to a unique dynamical definition of simultaneity. This opens up the prospect of a solution of the problem of time in quantum gravity on the basis of a fundamental dynamical principle.
NASA Astrophysics Data System (ADS)
Müller, A.
1994-09-01
One of the basic problems in science is the understanding of the potentialities of material systems, a topic which is of relevance for disciplines ranging from natural philosophy over topology and/or structural chemistry, and biology ( morphogenesis) to materials science. Information on this problem can be obtained by studying the different types of linking of basic fragments in self-assembly processes, a type of reaction which has proved to be one of the most important in the biological and material world. The outlined problem can be nicely studied in the case of polyoxometalates with reference to basic organizing principles of material systems like conservative self-organization ( self-assembly), host—guest interactions, complementarity, molecular recognition, emergence vs. reduction ( as a dialectic unit), template-direction, exchange-interactions and, in general, the mesoscopic material world with its unusual properties as well as its topological and/or structural diversity. Science will lose in significance as an interdisciplinary unit — as outlined or maybe predicted here — should not more importance be attached to general aspects in the future.
Bai, Sunhye; Reynolds, Bridget M.; Robles, Theodore F.; Repetti, Rena L.
2016-01-01
This study examined how academic and peer problems at school are linked to family interactions at home on the same day, using eight consecutive weeks of daily diary data collected from early adolescents (60% female; M age = 11.28, SD = 1.50), mothers and fathers in 47 families. On days when children reported more academic problems at school, they, but not their parents, reported less warmth and more conflict with mothers, and more conflict and less time spent around fathers. These effects were partially explained by same-day child reports of higher negative mood. Peer problems were less consistently associated with parent-child interactions over and above the effects of academic problems that day. A one-time measure of parent-child relationship quality moderated several daily associations, such that the same-day link between school problems and child-report of family interactions was stronger among children who were closer to their parents. PMID:29307958
NASA Astrophysics Data System (ADS)
Ma, Chuang; Bao, Zhong-Kui; Zhang, Hai-Feng
2017-10-01
So far, many network-structure-based link prediction methods have been proposed. However, these methods only highlight one or two structural features of networks, and then use the methods to predict missing links in different networks. The performances of these existing methods are not always satisfied in all cases since each network has its unique underlying structural features. In this paper, by analyzing different real networks, we find that the structural features of different networks are remarkably different. In particular, even in the same network, their inner structural features are utterly different. Therefore, more structural features should be considered. However, owing to the remarkably different structural features, the contributions of different features are hard to be given in advance. Inspired by these facts, an adaptive fusion model regarding link prediction is proposed to incorporate multiple structural features. In the model, a logistic function combing multiple structural features is defined, then the weight of each feature in the logistic function is adaptively determined by exploiting the known structure information. Last, we use the "learnt" logistic function to predict the connection probabilities of missing links. According to our experimental results, we find that the performance of our adaptive fusion model is better than many similarity indices.
The danger of being inattentive - ADHD symptoms and risky sexual behaviour in Russian adolescents.
Isaksson, J; Stickley, A; Koposov, R; Ruchkin, V
2018-01-01
Prior research has indicated that attention-deficit/hyperactivity disorder (ADHD) symptoms may be associated with an increased likelihood of engaging in risky sexual behaviour (RSB). However, research on this association among adolescents has been comparatively limited and mainly confined to North America. The aim of this study was to examine if inattention and hyperactivity/impulsivity symptoms were linked to RSB in a community cohort sample of Russian adolescents. The study was based on a group of 537 adolescents from Northern Russia. Information on inattention and hyperactivity/impulsivity as well as conduct problems was obtained through teacher ratings, while information on RSB (previous unprotected sex, number of sexual partners, sex while intoxicated and partner pregnancies), substance use, perception of risk, and parenting behaviour was based on students' self-reports. Binary logistic regression analysis was used to examine associations between the variables. Teacher-rated inattention symptoms predicted RSB, independently of co-morbid conduct problems, substance use, risk perception, and different parenting styles (parental warmth, involvement and control). In addition, male sex, binge drinking and a lower assessment of perceived risk were all significantly associated with RSB in an adjusted model. Neither teacher-rated hyperactivity/impulsivity symptoms nor conduct problems were linked to RSB in the full model. Deficits in planning and organizing behaviours, being easily distracted and forgetful seem to be of importance for RSB in Russian adolescents. This highlights the importance of discriminating between different ADHD symptoms in adolescence to prevent risk behaviours and their potentially detrimental outcomes on health and well-being. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Lithospheric Strength and Stress State: Persistent Challenges and New Directions in Geodynamics
NASA Astrophysics Data System (ADS)
Hirth, G.
2017-12-01
The strength of the lithosphere controls a broad array of geodynamic processes ranging from earthquakes, the formation and evolution of plate boundaries and the thermal evolution of the planet. A combination of laboratory, geologic and geophysical observations provides several independent constraints on the rheological properties of the lithosphere. However, several persistent challenges remain in the interpretation of these data. Problems related to extrapolation in both scale and time (rate) need to be addressed to apply laboratory data. Nonetheless, good agreement between extrapolation of flow laws and the interpretation of microstructures in viscously deformed lithospheric mantle rocks demonstrates a strong foundation to build on to explore the role of scale. Furthermore, agreement between the depth distribution of earthquakes and predictions based on extrapolation of high temperature friction relationships provides a basis to understand links between brittle deformation and stress state. In contrast, problems remain for rationalizing larger scale geodynamic processes with these same rheological constraints. For example, at face value the lab derived values for the activation energy for creep are too large to explain convective instabilities at the base of the lithosphere, but too low to explain the persistence of dangling slabs in the upper mantle. In this presentation, I will outline these problems (and successes) and provide thoughts on where new progress can be made to resolve remaining inconsistencies, including discussion of the role of the distribution of volatiles and alteration on the strength of the lithosphere, new data on the influence of pressure on friction and fracture strength, and links between the location of earthquakes, thermal structure, and stress state.
Brody, Gene H; Kim, Sooyeon; Murry, Velma McBride; Brown, Anita C
2004-01-01
A 4-wave longitudinal design was used to examine protective links from child competence to behavioral problems in first- (M=10.97 years) and second- (M=8.27 years) born rural African American children. At 1-year intervals, teachers assessed child behavioral problems, mothers reported their psychological functioning, and both mothers and children reported parenting practices. Structural equation modeling indicated that child competence was linked with residualized positive changes in mothers' psychological functioning from Wave 1 to Wave 2. Mothers' psychological functioning and child competence at Wave 2 forecast involved-supportive parenting at Wave 3, which was associated negatively with externalizing and internalizing problems at Wave 4. The importance of replicating processes leading to outcomes among children in the same study is discussed.
Dharmalingam, Rajasekaran; Dash, Subhransu Sekhar; Senthilnathan, Karthikrajan; Mayilvaganan, Arun Bhaskar; Chinnamuthu, Subramani
2014-01-01
This paper deals with the performance of unified power quality conditioner (UPQC) based on current source converter (CSC) topology. UPQC is used to mitigate the power quality problems like harmonics and sag. The shunt and series active filter performs the simultaneous elimination of current and voltage problems. The power fed is linked through common DC link and maintains constant real power exchange. The DC link is connected through the reactor. The real power supply is given by the photovoltaic system for the compensation of power quality problems. The reference current and voltage generation for shunt and series converter is based on phase locked loop and synchronous reference frame theory. The proposed UPQC-CSC design has superior performance for mitigating the power quality problems. PMID:25013854
Dharmalingam, Rajasekaran; Dash, Subhransu Sekhar; Senthilnathan, Karthikrajan; Mayilvaganan, Arun Bhaskar; Chinnamuthu, Subramani
2014-01-01
This paper deals with the performance of unified power quality conditioner (UPQC) based on current source converter (CSC) topology. UPQC is used to mitigate the power quality problems like harmonics and sag. The shunt and series active filter performs the simultaneous elimination of current and voltage problems. The power fed is linked through common DC link and maintains constant real power exchange. The DC link is connected through the reactor. The real power supply is given by the photovoltaic system for the compensation of power quality problems. The reference current and voltage generation for shunt and series converter is based on phase locked loop and synchronous reference frame theory. The proposed UPQC-CSC design has superior performance for mitigating the power quality problems.
Chen, Wan-Yi; Corvo, Kenneth; Lee, Yookyong; Hahm, Hyeouk Chris
2017-01-01
Research on the impact of exposure to community violence tends to define victimization as a single construct. This study differentiates between direct and indirect violence victimization in their association with mental health problems and mental health service use. This study includes 8947 individuals from four waves of the National Longitudinal Study of Adolescent to Adult Health and examines (1) whether sub-types of adolescent victimization are linked to depressive symptoms; (2) whether adolescent victimization is linked with mental health service use; and (3) the role of mental health service use in attenuating symptoms arising from victimizations. Adolescents witnessing community violence were more likely to experience depressive symptoms during adolescence but not during their young adulthood; direct exposure to violence during adolescence does not predict depressive symptoms in adolescence but does in adulthood. Use of mental health service mediates report of depressive symptoms for adolescent witnessing community violence.
A Cohesive Zone Approach for Fatigue-Driven Delamination Analysis in Composite Materials
NASA Astrophysics Data System (ADS)
Amiri-Rad, Ahmad; Mashayekhi, Mohammad
2017-08-01
A new model for prediction of fatigue-driven delamination in laminated composites is proposed using cohesive interface elements. The presented model provides a link between cohesive elements damage evolution rate and crack growth rate of Paris law. This is beneficial since no additional material parameters are required and the well-known Paris law constants are used. The link between the cohesive zone method and fracture mechanics is achieved without use of effective length which has led to more accurate results. The problem of unknown failure path in calculation of the energy release rate is solved by imposing a condition on the damage model which leads to completely vertical failure path. A global measure of energy release rate is used for the whole cohesive zone which is computationally more efficient compared to previous similar models. The performance of the proposed model is investigated by simulation of well-known delamination tests and comparison against experimental data of the literature.
[Victimization and alcohol problems in the families of disabled persons].
Farkas, Lajos; Kaló, Róbert; Gerevich, József
2006-01-01
Few research data are available on the addiction problems that occur in the families of persons living with disability. There is even less information on the extent of violence disabled people experience in their families as violence directed at them, and little is known how this is connected to alcohol and drug use that may occur in the families of the different groups of disabled persons as compared to healthy control samples. We sought an answer to this question through a case-control study involving 245 young people with disability and 60 healthy controls, using structured interview methods (EuropASI, EuroADAD) and self-assessment questionnaires (Temperament and Character Inventory, Juvenile Victimisation Questionnaire, Child Abuse and Trauma Scale). The presence of a drinking problem in the family was clearly identified as a predictor of an increased risk of victimization, of the occurrence of various types of victimization events, and of their greater frequency. The strong effect of a drinking problem in the family on substance use, psychiatric state and difficulties in aggression management was also confirmed. The predictive effect of a drinking problem was manifested in various ways in different disability groups. Our data draw attention to the link between victimization and drinking problems that can be observed in the families of disabled people, and to the importance of prevention which could help in improving the quality of life of the persons living with disability.
Osório, Ana A C; Rossi, Natália F; Gonçalves, Óscar F; Sampaio, Adriana; Giacheti, Célia M
2017-08-01
Several studies have documented the high prevalence of psychopathology and behavior problems in Williams syndrome (WS). However, the links between cognitive development and such symptoms need further clarification. Our study aims to expand current knowledge on levels of behavior problems and its links to cognition in a sample of Brazilian individuals with WS. A total of 25 children and adolescents with WS and their parents participated in this study. The participants' IQs were assessed with the Wechsler Scales of Intelligence (for children or adults) and parental reports of psychopathology/behavior problems were collected using the Child Behavior Checklist (CBCL). The presence of clinically significant attention problems was a main feature in our sample of children and adolescents with WS. In the children, higher IQ scores were found to be significantly associated with less externalizing problems, while in the adolescents cognitive abilities were found to be associated with less internalizing symptoms. These results provide further insight into the links between psychopathology and behavior problems and cognitive abilities in WS, and suggest the need to take age into consideration when analyzing such relationships.
Neural Activation during Inhibition Predicts Initiation of Substance Use in Adolescence
Norman, Andria L.; Pulido, Carmen; Squeglia, Lindsay M.; Spadoni, Andrea D.; Paulus, Martin P.; Tapert, Susan F.
2011-01-01
Background Problems inhibiting non-adaptive behaviors have been linked to an increased risk for substance use and other risk taking behaviors in adolescence. This study examines the hypothesis that abnormalities in neural activation during inhibition in early adolescence may predict subsequent substance involvement. Methods Thirty eight adolescents from local area middle schools, ages 12–14, with very limited histories of substance use, underwent functional magnetic resonance imaging (fMRI) as they performed a go/no-go task of response inhibition and response selection. Adolescents and their parents were then followed annually with interviews covering substance use and other behaviors. Based on follow-up data, youth were classified as transitioning to heavy use of alcohol (TU; n=21), or as healthy controls (CON; n=17). Results At baseline, prior to the onset of use, youth who later transitioned into heavy use of alcohol showed significantly less activation than those who went on to remain non to minimal users throughout adolescence. Activation reductions in TU at baseline were seen on no-go trials in 12 brain regions, including right inferior frontal gyrus, left dorsal and medial frontal areas, bilateral motor cortex, cingulate gyrus, left putamen, bilateral middle temporal gyri, and bilateral inferior parietal lobules (corrected p < .01, each cluster ≥ 32 contiguous voxels). Conclusions These results support the hypothesis that less neural activity during response inhibition demands predicts future involvement with problem behaviors such as alcohol and other substance use. PMID:21782354
Predicting Drug Safety and Communicating Risk: Benefits of a Bayesian Approach.
Lazic, Stanley E; Edmunds, Nicholas; Pollard, Christopher E
2018-03-01
Drug toxicity is a major source of attrition in drug discovery and development. Pharmaceutical companies routinely use preclinical data to predict clinical outcomes and continue to invest in new assays to improve predictions. However, there are many open questions about how to make the best use of available data, combine diverse data, quantify risk, and communicate risk and uncertainty to enable good decisions. The costs of suboptimal decisions are clear: resources are wasted and patients may be put at risk. We argue that Bayesian methods provide answers to all of these problems and use hERG-mediated QT prolongation as a case study. Benefits of Bayesian machine learning models include intuitive probabilistic statements of risk that incorporate all sources of uncertainty, the option to include diverse data and external information, and visualizations that have a clear link between the output from a statistical model and what this means for risk. Furthermore, Bayesian methods are easy to use with modern software, making their adoption for safety screening straightforward. We include R and Python code to encourage the adoption of these methods.
Parenting stress and development of late preterm infants at 4 months corrected age.
Mughal, Muhammad K; Ginn, Carla S; Magill-Evans, Joyce; Benzies, Karen M
2017-10-01
Parenting stress has been linked to child development issues in early preterm infants, but less is known about its effects on development in infants born late preterm. We examined relationships between parenting stress of 108 mothers and 108 fathers and development of late preterm infants born at 34 0/7 to 36 6/7 weeks gestation. At 4 months corrected age, mothers and fathers completed the Parenting Stress Index (PSI-3); mothers were primary caregivers in almost all families and completed the Ages and Stages Questionnaire (ASQ-2) on child development. Mothers reported significantly more stress than fathers on the PSI-3 Parent Domain. PSI-3 subscale scores from the Child Domain were significant predictors of mother-reported infant development as measured by the ASQ-2 in regression models: Reinforces Parent predicted Gross Motor, Mood predicted Communication, and Acceptability predicted Communication, Fine Motor, Problem Solving, and Personal -Social development scale scores. Experiences of parenting stress differed for mothers and fathers. Further research is required on specific dimensions of parenting stress related to development of late preterm infants. © 2017 Wiley Periodicals, Inc.
Classification of Phylogenetic Profiles for Protein Function Prediction: An SVM Approach
NASA Astrophysics Data System (ADS)
Kotaru, Appala Raju; Joshi, Ramesh C.
Predicting the function of an uncharacterized protein is a major challenge in post-genomic era due to problems complexity and scale. Having knowledge of protein function is a crucial link in the development of new drugs, better crops, and even the development of biochemicals such as biofuels. Recently numerous high-throughput experimental procedures have been invented to investigate the mechanisms leading to the accomplishment of a protein’s function and Phylogenetic profile is one of them. Phylogenetic profile is a way of representing a protein which encodes evolutionary history of proteins. In this paper we proposed a method for classification of phylogenetic profiles using supervised machine learning method, support vector machine classification along with radial basis function as kernel for identifying functionally linked proteins. We experimentally evaluated the performance of the classifier with the linear kernel, polynomial kernel and compared the results with the existing tree kernel. In our study we have used proteins of the budding yeast saccharomyces cerevisiae genome. We generated the phylogenetic profiles of 2465 yeast genes and for our study we used the functional annotations that are available in the MIPS database. Our experiments show that the performance of the radial basis kernel is similar to polynomial kernel is some functional classes together are better than linear, tree kernel and over all radial basis kernel outperformed the polynomial kernel, linear kernel and tree kernel. In analyzing these results we show that it will be feasible to make use of SVM classifier with radial basis function as kernel to predict the gene functionality using phylogenetic profiles.
Taylor, Peter J; Wood, Alex M
2013-09-01
Parental appraisals of an adolescent may have an effect upon the adolescent's well-being and likelihood of emotional problems. However, the impact of these parental appraisals is likely to be partly determined by the young person's self-appraisal. It was predicted that a discrepancy in self- and parent appraisals of positive, prosocial qualities would be associated with an increased risk of emotional problems. The study employed a cross-sectional design within a large sample of adolescent and caregiver dyads (N = 3,976, aged 11-17 years), drawn from the 'Mental health of children and young people in Great Britain, 2004' survey. Two separate measures of prosociality were used to ensure that effects were not specific to one measure. The analysis explored the discrepancy in parent and self-ratings on these measures via interactions within a logistic regression framework. Potential confounds, including gender, parental mental health, conduct and hyperkinetic problems were controlled for in the analysis. The logistic regression analyses demonstrated significant interactions between self- and parent ratings of prosocial qualities in predicting the odds of emotional disorder (i.e., depression and anxiety). This effect occurred across both measures of prosocial qualities whilst controlling for confounds. The pattern of the interactions suggested that low parental appraisals had a more detrimental effect on well-being when self-appraisals were highly positive. The results suggest that moderately high self-appraised positive traits may carry a cost of leaving young people more vulnerable to discrepant, negative parental appraisals. This has important implications for the meaning attributed to self-appraised positive traits in clinical contexts. Clinicians should be aware that the association between parental perceptions of a child's prosociality and emotional disorder may be influenced by the adolescents' self-perceptions. Clinicians should therefore endeavour to assess both parental and adolescent appraisals. Discrepancies may be clinically meaningful, in terms of the risk of emotional problems, rather than simply being a nuisance. This study is cross-sectional, so although discrepancies may be linked to risk of emotional problems, the direction of this effect requires elucidation. The current study only focusses on the parent-adolescent dynamic and so may not extend to discrepancy effects in other areas of positive functioning or in other relational contexts. © 2012 The British Psychological Society.
Flouri, Eirini
2006-03-01
Few studies have investigated if mother's interest and father's interest in child's education are linked to educational attainment via their impact on child's self-esteem and locus of control. (1) To investigate (after controlling for known confounding factors) the long-term effect of mother's and father's interest in child's education at age 10 and child's locus of control and self-esteem at age 10 in educational attainment at age 26; and (2) to explore if mother's interest and father's interest in child's education are linked to child's educational attainment via their effect in increasing child's self-esteem and internal locus of control. The study used longitudinal data from sweeps of the 1970 British Cohort Study (BCS70). The initial sample was those 1,737 men and 2,033 women with valid data on age 10 self-esteem, locus of control, father's interest, mother's interest, and age 26 educational attainment. Of these, 1,326 men and 1,578 women were included in the final analysis. The birth to age 10 factors that were controlled for were birth weight, parental social class, socio-economic disadvantage, emotional/behavioural problems, cognitive ability, and mother's educational attainment. At the multivariate level, internal locus of control and mother's interest (but not self-esteem) were significantly related to educational attainment in both men and women. Father's interest was a significant predictor of educational attainment only in women. Parent's interest was not linked to educational attainment via its impact on child's self-esteem or locus of control. Self-esteem predicted educational attainment in both genders by increasing internal locus of control, and fathers' interest predicted educational attainment in men by increasing mother's involvement. Although mothers' and fathers' interest in their children's education were not linked to educational attainment via their impact on children's self-esteem or locus of control, they were significant predictors of educational attainment especially in daughters.
Scrimgeour, Meghan B; Davis, Elizabeth L; Buss, Kristin A
2016-01-01
Prosocial behavior in early childhood is a precursor to later adaptive social functioning. This investigation leveraged mother-reported, physiological, and observational data to examine children's prosocial development from age 2 to age 4 (N = 125). Maternal emotion socialization (ES) strategies and children's parasympathetic regulation have each been implicated in prosocial behavior, but are rarely examined together or prospectively. Given the transactional nature of parent-child relationships, the effects of maternal ES strategies on children's prosocial behavior are likely moderated by children's individual differences in parasympathetic regulation. As expected, mothers' reported use of problem-focused ES strategies predicted prosocial behavior at age 4. Additionally, children who showed parasympathetic reactivity consistent with more effective emotion regulation during a lab-based disappointment task were rated as more prosocial at age 4. Several interactions with maternal ES strategies emerged. Children's parasympathetic regulation moderated the relations between observed physical comfort or cognitive reframing and prosocial behavior. Observed distraction (either behavioral or cognitive) moderated the link between mothers' reported use of problem-focused ES strategies and children's prosocial behavior. Findings suggest that children's emerging prosocial behavior is shaped by the interactive contributions of interpersonal maternal ES as well as intrapersonal intrinsic physiological regulation. (PsycINFO Database Record (c) 2015 APA, all rights reserved).
Mental health antecedents of early midlife insomnia: evidence from a four-decade longitudinal study.
Goldman-Mellor, Sidra; Gregory, Alice M; Caspi, Avshalom; Harrington, HonaLee; Parsons, Michael; Poulton, Richie; Moffitt, Terrie E
2014-11-01
Insomnia is a highly prevalent condition that constitutes a major public health and economic burden. However, little is known about the developmental etiology of adulthood insomnia. We examined whether indicators of psychological vulnerability across multiple developmental periods (psychiatric diagnoses in young adulthood and adolescence, childhood behavioral problems, and familial psychiatric history) predicted subsequent insomnia in adulthood. We used data from the ongoing Dunedin Multidisciplinary Health and Development Study, a population-representative birth cohort study of 1,037 children in New Zealand who were followed prospectively from birth (1972-1973) through their fourth decade of life with a 95% retention rate. Insomnia was diagnosed at age 38 according to DSM-IV criteria. Psychiatric diagnoses, behavioral problems, and family psychiatric histories were assessed between ages 5 and 38. In cross-sectional analyses, insomnia was highly comorbid with multiple psychiatric disorders. After controlling for this concurrent comorbidity, our results showed that individuals who have family histories of depression or anxiety, and who manifest lifelong depression and anxiety beginning in childhood, are at uniquely high risk for age-38 insomnia. Other disorders did not predict adulthood insomnia. The link between lifelong depression and anxiety symptoms and adulthood insomnia calls for further studies to clarify the neurophysiological systems or behavioral conditioning processes that may underlie this association.
Hasler, Brant P.; Casement, Melynda D.; Sitnick, Stephanie L.; Shaw, Daniel S.; Forbes, Erika E.
2017-01-01
Eveningness, a preference for later sleep-wake timing, is linked to altered reward function, which may explain a consistent association with substance abuse. Notably, the extant literature rests largely on cross-sectional data, yet both eveningness and reward function show developmental changes. We examined whether circadian preference during late adolescence predicted the neural response to reward two years later. A sample of 93 males reported circadian preference and completed a monetary reward fMRI paradigm at ages 20 and 22. Primary analyses examined longitudinal paths from circadian preference to medial prefrontal cortex (mPFC) and ventral striatal (VS) reward responses. We also explored whether reward responses mediated longitudinal associations between circadian preference and alcohol dependence, frequency of alcohol use, and/or frequency of cannabis use. Age 20 eveningness was positively associated with age 22 mPFC and VS responses to win, but not associated with age 22 reactivity to reward anticipation. Age 20 eveningness was indirectly related to age 22 alcohol dependence via age 22 mPFC response to win. Our findings provide novel evidence that altered reward-related brain function could underlie associations between eveningness and alcohol use problems. Eveningness may be an under-recognized but modifiable risk factor for reward-related problems such as mood and substance use disorders. PMID:28254633
Ranking in evolving complex networks
NASA Astrophysics Data System (ADS)
Liao, Hao; Mariani, Manuel Sebastian; Medo, Matúš; Zhang, Yi-Cheng; Zhou, Ming-Yang
2017-05-01
Complex networks have emerged as a simple yet powerful framework to represent and analyze a wide range of complex systems. The problem of ranking the nodes and the edges in complex networks is critical for a broad range of real-world problems because it affects how we access online information and products, how success and talent are evaluated in human activities, and how scarce resources are allocated by companies and policymakers, among others. This calls for a deep understanding of how existing ranking algorithms perform, and which are their possible biases that may impair their effectiveness. Many popular ranking algorithms (such as Google's PageRank) are static in nature and, as a consequence, they exhibit important shortcomings when applied to real networks that rapidly evolve in time. At the same time, recent advances in the understanding and modeling of evolving networks have enabled the development of a wide and diverse range of ranking algorithms that take the temporal dimension into account. The aim of this review is to survey the existing ranking algorithms, both static and time-aware, and their applications to evolving networks. We emphasize both the impact of network evolution on well-established static algorithms and the benefits from including the temporal dimension for tasks such as prediction of network traffic, prediction of future links, and identification of significant nodes.
Samaco, Rodney C.; Fryer, John D.; Ren, Jun; Fyffe, Sharyl; Chao, Hsiao-Tuan; Sun, Yaling; Greer, John J.; Zoghbi, Huda Y.; Neul, Jeffrey L.
2008-01-01
Rett Syndrome, an X-linked dominant neurodevelopmental disorder characterized by regression of language and hand use, is primarily caused by mutations in methyl-CpG-binding protein 2 (MECP2). Loss of function mutations in MECP2 are also found in other neurodevelopmental disorders such as autism, Angelman-like syndrome and non-specific mental retardation. Furthermore, duplication of the MECP2 genomic region results in mental retardation with speech and social problems. The common features of human neurodevelopmental disorders caused by the loss or increase of MeCP2 function suggest that even modest alterations of MeCP2 protein levels result in neurodevelopmental problems. To determine whether a small reduction in MeCP2 level has phenotypic consequences, we characterized a conditional mouse allele of Mecp2 that expresses 50% of the wild-type level of MeCP2. Upon careful behavioral analysis, mice that harbor this allele display a spectrum of abnormalities such as learning and motor deficits, decreased anxiety, altered social behavior and nest building, decreased pain recognition and disrupted breathing patterns. These results indicate that precise control of MeCP2 is critical for normal behavior and predict that human neurodevelopmental disorders will result from a subtle reduction in MeCP2 expression. PMID:18321864
National Centers for Environmental Prediction
: Monsoon progress image (Link) IITM : 2017 Monsoon (Link) SW Monsoon, 2016 IMD : Daily rainfall report (30th September, 2016) (Link) IMD : End of season Monsoon Report (2016) (Link) SW Monsoon, 2015 IMD : Daily rainfall report (30th September, 2015) (Link) IMD : End of season Monsoon Report (2015) (Link
Cannistraci, Carlo Vittorio; Alanis-Lobato, Gregorio; Ravasi, Timothy
2013-01-01
Growth and remodelling impact the network topology of complex systems, yet a general theory explaining how new links arise between existing nodes has been lacking, and little is known about the topological properties that facilitate link-prediction. Here we investigate the extent to which the connectivity evolution of a network might be predicted by mere topological features. We show how a link/community-based strategy triggers substantial prediction improvements because it accounts for the singular topology of several real networks organised in multiple local communities - a tendency here named local-community-paradigm (LCP). We observe that LCP networks are mainly formed by weak interactions and characterise heterogeneous and dynamic systems that use self-organisation as a major adaptation strategy. These systems seem designed for global delivery of information and processing via multiple local modules. Conversely, non-LCP networks have steady architectures formed by strong interactions, and seem designed for systems in which information/energy storage is crucial. PMID:23563395
Cannistraci, Carlo Vittorio; Alanis-Lobato, Gregorio; Ravasi, Timothy
2013-01-01
Growth and remodelling impact the network topology of complex systems, yet a general theory explaining how new links arise between existing nodes has been lacking, and little is known about the topological properties that facilitate link-prediction. Here we investigate the extent to which the connectivity evolution of a network might be predicted by mere topological features. We show how a link/community-based strategy triggers substantial prediction improvements because it accounts for the singular topology of several real networks organised in multiple local communities - a tendency here named local-community-paradigm (LCP). We observe that LCP networks are mainly formed by weak interactions and characterise heterogeneous and dynamic systems that use self-organisation as a major adaptation strategy. These systems seem designed for global delivery of information and processing via multiple local modules. Conversely, non-LCP networks have steady architectures formed by strong interactions, and seem designed for systems in which information/energy storage is crucial.
Optical link by using optical wiring method for reducing EMI
NASA Astrophysics Data System (ADS)
Cho, In-Kui; Kwon, Jong-Hwa; Choi, Sung-Woong; Bondarik, Alexander; Yun, Je-Hoon; Kim, Chang-Joo; Ahn, Seung-Beom; Jeong, Myung-Yung; Park, Hyo Hoon
2008-12-01
A practical optical link system was prepared with a transmitter (Tx) and receiver (Rx) for reducing EMI (electromagnetic interference). The optical TRx module consisted of a metal optical bench, a module printed circuit board (PCB), a driver/receiver IC, a VCSEL/PD array, and an optical link block composed of plastic optical fiber (POF). For the optical interconnection between the light-sources and detectors, an optical wiring method has been proposed to enable easy assembly. The key benefit of fiber optic link is the absence of electromagnetic interference (EMI) noise creation and susceptibility. This paper provides a method for optical interconnection between an optical Tx and an optical Rx, comprising the following steps: (i) forming a light source device, an optical detection device, and an optical transmission unit on a substrate (metal optical bench (MOB)); (ii) preparing a flexible optical transmission-connection medium (optical wiring link) to optically connect the light source device formed on the substrate with the optical detection device; and (iii) directly connecting one end of the surface-finished optical transmission connection medium with the light source device and the other end with the optical detection device. Electronic interconnections have uniquely electronic problems such as EMI, shorting, and ground loops. Since these problems only arise during transduction (electronics-to-optics or opticsto- electronics), the purely optical part and optical link(interconnection) is free of these problems. 1 An optical link system constructed with TRx modules was fabricated and the optical characteristics about data links and EMI levels were measured. The results clearly demonstrate that the use of an optical wiring method can provide robust and cost-effective assembly for reducing EMI of inter-chip interconnect. We successfully achieved a 4.5 Gb/s data transmission rate without EMI problems.
Hodge, Meryl C; Dixon, Stephanie; Garg, Amit X; Clemens, Kristin K
2017-06-01
To determine the positive predictive value and sensitivity of an International Statistical Classification of Diseases and Related Health Problems, 10th Revision, coding algorithm for hospital encounters concerning hypoglycemia. We carried out 2 retrospective studies in Ontario, Canada. We examined medical records from 2002 through 2014, in which older adults (mean age, 76) were assigned at least 1 code for hypoglycemia (E15, E160, E161, E162, E1063, E1163, E1363, E1463). The positive predictive value of the algorithm was calculated using a gold-standard definition (blood glucose value <4 mmol/L or physician diagnosis of hypoglycemia). To determine the algorithm's sensitivity, we used linked healthcare databases to identify older adults (mean age, 77) with laboratory plasma glucose values <4 mmol/L during a hospital encounter that took place between 2003 and 2011. We assessed how frequently a code for hypoglycemia was present. We also examined the algorithm's performance in differing clinical settings (e.g. inpatient vs. emergency department, by hypoglycemia severity). The positive predictive value of the algorithm was 94.0% (95% confidence interval 89.3% to 97.0%), and its sensitivity was 12.7% (95% confidence interval 11.9% to 13.5%). It performed better in the emergency department and in cases of more severe hypoglycemia (plasma glucose values <3.5 mmol/L compared with ≥3.5 mmol/L). Our hypoglycemia algorithm has a high positive predictive value but is limited in sensitivity. Although we can be confident that older adults who are assigned 1 of these codes truly had a hypoglycemia event, many episodes will not be captured by studies using administrative databases. Copyright © 2017 Diabetes Canada. Published by Elsevier Inc. All rights reserved.
A Constant-Factor Approximation Algorithm for the Link Building Problem
NASA Astrophysics Data System (ADS)
Olsen, Martin; Viglas, Anastasios; Zvedeniouk, Ilia
In this work we consider the problem of maximizing the PageRank of a given target node in a graph by adding k new links. We consider the case that the new links must point to the given target node (backlinks). Previous work [7] shows that this problem has no fully polynomial time approximation schemes unless P = NP. We present a polynomial time algorithm yielding a PageRank value within a constant factor from the optimal. We also consider the naive algorithm where we choose backlinks from nodes with high PageRank values compared to the outdegree and show that the naive algorithm performs much worse on certain graphs compared to the constant factor approximation scheme.
Polarization rotation in meteor burst communication systems
NASA Astrophysics Data System (ADS)
Cannon, P. S.
1986-06-01
Theoretical modeling of several meteor burst communication (MBC) paths indicates that polarization rotation losses are significant for a linearly polarized system operating near 40 MHz. Losses for a hybrid system with physical installation problems, consisting of linearly polarized transmitting and circularly polarized receiving antennas, were found to be less. Both ionospheric Faraday rotation polarization changes, and underdense meteor trail scattering wave polarization rotation, are considered. These losses are found to cause a 15-70 percent data throughput reduction of the value predicted for the situation without polarization rotation, in the two 40-MHz linearly polarized links considered for noon summer solstice conditions during high solar sunspot number periods. Qualitative experimental confirmation is provided through a cross polarization approach.
Data Parallel Line Relaxation (DPLR) Code User Manual: Acadia - Version 4.01.1
NASA Technical Reports Server (NTRS)
Wright, Michael J.; White, Todd; Mangini, Nancy
2009-01-01
Data-Parallel Line Relaxation (DPLR) code is a computational fluid dynamic (CFD) solver that was developed at NASA Ames Research Center to help mission support teams generate high-value predictive solutions for hypersonic flow field problems. The DPLR Code Package is an MPI-based, parallel, full three-dimensional Navier-Stokes CFD solver with generalized models for finite-rate reaction kinetics, thermal and chemical non-equilibrium, accurate high-temperature transport coefficients, and ionized flow physics incorporated into the code. DPLR also includes a large selection of generalized realistic surface boundary conditions and links to enable loose coupling with external thermal protection system (TPS) material response and shock layer radiation codes.
ERIC Educational Resources Information Center
Kim-Spoon, Jungmeen.; Haskett, Mary E.; Longo, Gregory S.; Nice, Rachel.
2012-01-01
Objective: Research using normative and high-risk samples indicates a significant link between problems with self-regulation and child maladjustment. Nevertheless, little is known about the processes that may modify the link between self-regulation and maladjustment. This longitudinal study examined the joint contributions of child self-regulation…
The Link between Food Ingested and Problem Behavior: Fact or Fallacy?
ERIC Educational Resources Information Center
Pescara-Kovach, Lisa A.; Alexander, Kristi
1994-01-01
Past and current research on the effects of foods ingested and food allergies on hyperactivity and other behavior problems are examined in this article. It is argued that evidence supporting a link between diet and behavior is lacking. Methods for correcting widespread public misconceptions on this subject are also discussed. (Author/PB)
The Chain-Link Fence Model: A Framework for Creating Security Procedures
ERIC Educational Resources Information Center
Houghton, Robert F.
2013-01-01
A long standing problem in information technology security is how to help reduce the security footprint. Many specific proposals exist to address specific problems in information technology security. Most information technology solutions need to be repeatable throughout the course of an information systems lifecycle. The Chain-Link Fence Model is…
Hydrostatic Pressure Project: Linked-Class Problem-Based Learning in Engineering
ERIC Educational Resources Information Center
Davis, Freddie J.; Lockwood-Cooke, Pamela; Hunt, Emily M.
2011-01-01
Over the last few years, WTAMU Mathematics, Engineering and Science faculty has used interdisciplinary projects as the basis for implementation of a linked-class approach to Problem-Based Learning (PBL). A project that has significant relevance to engineering statics, fluid mechanics, and calculus is the Hydrostatic Pressure Project. This project…
ERIC Educational Resources Information Center
Coley, Rebekah Levine; Carrano, Jennifer; Lewin-Bizan, Selva
2011-01-01
Building upon previous evidence for the intergenerational transmission of antisocial behaviors, this research assessed and compared three models seeking to explain links between fathers' antisocial behaviors and children's behavior problems. A representative sample of children from low-income families (N = 261) was followed from age 3 through age…
Grossi, Enzo
2006-01-01
Background In recent years a number of algorithms for cardiovascular risk assessment has been proposed to the medical community. These algorithms consider a number of variables and express their results as the percentage risk of developing a major fatal or non-fatal cardiovascular event in the following 10 to 20 years Discussion The author has identified three major pitfalls of these algorithms, linked to the limitation of the classical statistical approach in dealing with this kind of non linear and complex information. The pitfalls are the inability to capture the disease complexity, the inability to capture process dynamics, and the wide confidence interval of individual risk assessment. Artificial Intelligence tools can provide potential advantage in trying to overcome these limitations. The theoretical background and some application examples related to artificial neural networks and fuzzy logic have been reviewed and discussed. Summary The use of predictive algorithms to assess individual absolute risk of cardiovascular future events is currently hampered by methodological and mathematical flaws. The use of newer approaches, such as fuzzy logic and artificial neural networks, linked to artificial intelligence, seems to better address both the challenge of increasing complexity resulting from a correlation between predisposing factors, data on the occurrence of cardiovascular events, and the prediction of future events on an individual level. PMID:16672045
Increasing the value of geospatial informatics with open approaches for Big Data
NASA Astrophysics Data System (ADS)
Percivall, G.; Bermudez, L. E.
2017-12-01
Open approaches to big data provide geoscientists with new capabilities to address problems of unmatched size and complexity. Consensus approaches for Big Geo Data have been addressed in multiple international workshops and testbeds organized by the Open Geospatial Consortium (OGC) in the past year. Participants came from government (NASA, ESA, USGS, NOAA, DOE); research (ORNL, NCSA, IU, JPL, CRIM, RENCI); industry (ESRI, Digital Globe, IBM, rasdaman); standards (JTC 1/NIST); and open source software communities. Results from the workshops and testbeds are documented in Testbed reports and a White Paper published by the OGC. The White Paper identifies the following set of use cases: Collection and Ingest: Remote sensed data processing; Data stream processing Prepare and Structure: SQL and NoSQL databases; Data linking; Feature identification Analytics and Visualization: Spatial-temporal analytics; Machine Learning; Data Exploration Modeling and Prediction: Integrated environmental models; Urban 4D models. Open implementations were developed in the Arctic Spatial Data Pilot using Discrete Global Grid Systems (DGGS) and in Testbeds using WPS and ESGF to publish climate predictions. Further development activities to advance open implementations of Big Geo Data include the following: Open Cloud Computing: Avoid vendor lock-in through API interoperability and Application portability. Open Source Extensions: Implement geospatial data representations in projects from Apache, Location Tech, and OSGeo. Investigate parallelization strategies for N-Dimensional spatial data. Geospatial Data Representations: Schemas to improve processing and analysis using geospatial concepts: Features, Coverages, DGGS. Use geospatial encodings like NetCDF and GeoPackge. Big Linked Geodata: Use linked data methods scaled to big geodata. Analysis Ready Data: Support "Download as last resort" and "Analytics as a service". Promote elements common to "datacubes."
A Near-Term Concept for Trajectory Based Operations with Air/Ground Data Link Communication
NASA Technical Reports Server (NTRS)
McNally, David; Mueller, Eric; Thipphavong, David; Paielli, Russell; Cheng, Jinn-Hwei; Lee, Chuhan; Sahlman, Scott; Walton, Joe
2010-01-01
An operating concept and required system components for trajectory-based operations with air/ground data link for today's en route and transition airspace is proposed. Controllers are fully responsible for separation as they are today, and no new aircraft equipage is required. Trajectory automation computes integrated solutions to problems like metering, weather avoidance, traffic conflicts and the desire to find and fly more time/fuel efficient flight trajectories. A common ground-based system supports all levels of aircraft equipage and performance including those equipped and not equipped for data link. User interface functions for the radar controller's display make trajectory-based clearance advisories easy to visualize, modify if necessary, and implement. Laboratory simulations (without human operators) were conducted to test integrated operation of selected system components with uncertainty modeling. Results are based on 102 hours of Fort Worth Center traffic recordings involving over 37,000 individual flights. The presence of uncertainty had a marginal effect (5%) on minimum-delay conflict resolution performance, and windfavorable routes had no effect on detection and resolution metrics. Flight plan amendments and clearances were substantially reduced compared to today s operations. Top-of-descent prediction errors are the largest cause of failure indicating that better descent predictions are needed to reliably achieve fuel-efficient descent profiles in medium to heavy traffic. Improved conflict detections for climbing flights could enable substantially more continuous climbs to cruise altitude. Unlike today s Conflict Alert, tactical automation must alert when an altitude amendment is entered, but before the aircraft starts the maneuver. In every other failure case tactical automation prevented losses of separation. A real-time prototype trajectory trajectory-automation system is running now and could be made ready for operational testing at an en route Center in 1-2 years.
National Centers for Environmental Prediction
---------------------------------------------------------------------------------------------------------------------------------------------------- IITM CFS v2 Forecast for 2017 monsoon : link Experimental short-range GEFS ensemble forecast : link Experimental short-range GFS-T1534(upto 8days) forecast : link
The growing problems of dental caries and obesity: an Australian perspective.
Hopcraft, M S; Beaumont, S
2016-10-07
Preventable diet-related diseases such as dental caries and obesity are a growing global problem, causing a significant burden on public health systems. Although there has been good evidence for the links between sugar consumption and dental caries for many decades, we are now seeing stronger links implicating sugar in obesity. There is a growing worldwide movement to tackle these problems by targeting the consumption of sugar-sweetened beverages through a range of public policy measures.
Experimental validation of predicted cancer genes using FRET
NASA Astrophysics Data System (ADS)
Guala, Dimitri; Bernhem, Kristoffer; Ait Blal, Hammou; Jans, Daniel; Lundberg, Emma; Brismar, Hjalmar; Sonnhammer, Erik L. L.
2018-07-01
Huge amounts of data are generated in genome wide experiments, designed to investigate diseases with complex genetic causes. Follow up of all potential leads produced by such experiments is currently cost prohibitive and time consuming. Gene prioritization tools alleviate these constraints by directing further experimental efforts towards the most promising candidate targets. Recently a gene prioritization tool called MaxLink was shown to outperform other widely used state-of-the-art prioritization tools in a large scale in silico benchmark. An experimental validation of predictions made by MaxLink has however been lacking. In this study we used Fluorescence Resonance Energy Transfer, an established experimental technique for detection of protein-protein interactions, to validate potential cancer genes predicted by MaxLink. Our results provide confidence in the use of MaxLink for selection of new targets in the battle with polygenic diseases.
Link-Based Similarity Measures Using Reachability Vectors
Yoon, Seok-Ho; Kim, Ji-Soo; Ryu, Minsoo; Choi, Ho-Jin
2014-01-01
We present a novel approach for computing link-based similarities among objects accurately by utilizing the link information pertaining to the objects involved. We discuss the problems with previous link-based similarity measures and propose a novel approach for computing link based similarities that does not suffer from these problems. In the proposed approach each target object is represented by a vector. Each element of the vector corresponds to all the objects in the given data, and the value of each element denotes the weight for the corresponding object. As for this weight value, we propose to utilize the probability of reaching from the target object to the specific object, computed using the “Random Walk with Restart” strategy. Then, we define the similarity between two objects as the cosine similarity of the two vectors. In this paper, we provide examples to show that our approach does not suffer from the aforementioned problems. We also evaluate the performance of the proposed methods in comparison with existing link-based measures, qualitatively and quantitatively, with respect to two kinds of data sets, scientific papers and Web documents. Our experimental results indicate that the proposed methods significantly outperform the existing measures. PMID:24701188
Performance analysis of rain attenuation on earth-to-satellite microwave links design in Libya
NASA Astrophysics Data System (ADS)
Rafiqul Islam, Md; Hussein Budalal, Asma Ali; Habaebi, Mohamed H.; Badron, Khairayu; Fadzil Ismail, Ahmad
2017-11-01
Performances of earth-to-satellite microwave links operating in Ku, Ka, and V-bands are degraded by the environment and strongly attenuated by rain. Rain attenuation is the most significant consideration and challenge to design a reliable earth-to-satellite microwave links for these frequency bands. Hence, it is essential for satellite link designer to take into account rain fade margin accurately before system implementation. Rain rate is the main measured parameter to predict of rain attenuation. Rainfall statistical data measured and recorded in Libya for the period of 30 years are collected from 5 locations. The prediction methods require one minute integration time rain intensity. Therefore, collected data were analyzed and processed to convert into one-minute rain rate cumulative distribution in Libya. The model proposed by ITU-R is used to predict and investigate rain fade based on converted 1-minute rain rate data. Rain fade predicted at two locations are used for performance analysis in terms of link spectral efficiency and throughput. V-band downlink shows that 99.99% availability is possible in all the Southern part stations in Libya at 0.29 bps/Hz spectral efficiency and 20.74 Mbps throughput when 72 MHz transponder band width is used which is not feasible in Northern part. Results of this paper will be a very useful resource to design highly reliable earth-to-satellite communication links in Libya.
Optical PAyload for Lasercomm Science (OPALS) link validation
NASA Technical Reports Server (NTRS)
Biswas, Abhijit; Oaida, Bogdan V.; Andrews, Kenneth S.; Kovalik, Joseph M.; Abrahamson, Matthew J.; Wright, Malcolm W.
2015-01-01
Recently several day and nighttime links under diverse atmospheric conditions were completed using the Optical Payload for Lasercomm Science (OPALS) flight system on-board the International Space Station (ISS). In this paper we compare measured optical power and its variance at either end of the link with predictions that include atmospheric propagation models. For the 976 nm laser beacon mean power transmitted from the ground to the ISS the predicted mean irradiance of 10's of microwatts per square meter close to zenith and its decrease with range and increased air mass shows good agreement with predictions. The irradiance fluctuations sampled at 100 Hz also follow the expected increase in scintillation with air mass representative of atmospheric coherence lengths at zenith at 500 nm in the 3-8 cm range. The downlink predicted power of 100's of nanowatts was also reconciled within the uncertainty of the atmospheric losses. Expected link performance with uncoded bit-error rates less than 1E-4 required for the Reed-Solomon code to correct errors for video, text and file transmission was verified. The results of predicted and measured powers and fluctuations suggest the need for further study and refinement.
Bandyopadhyay, Pradipta; Kuntz, Irwin D
2009-01-01
The determination of protein structure using distance constraints is a new and promising field of study. One implementation involves attaching residues of a protein using a cross-linking agent, followed by protease digestion, analysis of the resulting peptides by mass spectroscopy, and finally sequence threading to detect the protein folds. In the present work, we carry out computational modeling of the kinetics of cross-linking reactions in proteins using the master equation approach. The rate constants of the cross-linking reactions are estimated using the pKas and the solvent-accessible surface areas of the residues involved. This model is tested with fibroblast growth factor (FGF) and cytochrome C. It is consistent with the initial experimental rate data for individual lysine residues for cytochrome C. Our model captures all observed cross-links for FGF and almost 90% of the observed cross-links for cytochrome C, although it also predicts cross-links that were not observed experimentally (false positives). However, the analysis of the false positive results is complicated by the fact that experimental detection of cross-links can be difficult and may depend on specific experimental conditions such as pH, ionic strength. Receiver operator characteristic plots showed that our model does a good job in predicting the observed cross-links. Molecular dynamics simulations showed that for cytochrome C, in general, the two lysines come closer for the observed cross-links as compared to the false positive ones. For FGF, no such clear pattern exists. The kinetic model and MD simulation can be used to study proposed cross-linking protocols.
Childhood physical punishment and the onset of drinking problems: evidence from metropolitan China
Cheng, Hui G.; Anthony, James C.; Huang, Yuequin; Lee, Sing; Liu, Zhaorui; He, Yanling
2011-01-01
Background Evidence in support of a suspected causal association linking childhood physical punishment (CPP) and later alcoholic beverage-related disturbances has been found in metropolitan China. Here, the focus shifts to the CPP association with the estimated risk of starting to drink, having the first drinking problem, and transitioning from first drink to the first drinking problem. Methods Data are from the World Mental Health Surveys-metropolitan China study, with representative samples of adult household residents living in two metropolitan cities, Beijing and Shanghai. Recalled information was available for early life experiences (including CPP, other childhood adversities, and parental alcohol and drug problems), as well as the onset age of drinking and drinking problems. Survival analyses were used to estimate the hazard ratio. A structural equation modeling approach was used to control for other inter-correlated childhood adversities. Results Cox proportional hazards modeling discloses statistically robust associations linking CPP with drinking and drinking problems, as well as more rapid transitions from first drink to first drinking problem, even after accounting for other childhood adversities and parental drinking problems. These associations cannot be attributed to a more general noxious family environment. Conclusions These results lay a foundation for future experimental studies on the possible causal relationship linking CPP with the onset of drinking problems and the transition from drinking to drinking problems. PMID:21474254
Genetics Home Reference: lipoid proteinosis
... Problems National Alliance on Mental Illness Pediatric Dermatology Research Alliance GeneReviews (1 link) Lipoid Proteinosis Scientific Articles on PubMed (1 link) PubMed OMIM (1 link) LIPOID PROTEINOSIS OF URBACH AND WIETHE MedGen (1 link) Lipid proteinosis Sources for This Page Callizo M, Ibáñez- ...
NASA Astrophysics Data System (ADS)
Desai, Priyanka Subhash
Rheology properties are sensitive indicators of molecular structure and dynamics. The relationship between rheology and polymer dynamics is captured in the constitutive model, which, if accurate and robust, would greatly aid molecular design and polymer processing. This dissertation is thus focused on building accurate and quantitative constitutive models that can help predict linear and non-linear viscoelasticity. In this work, we have used a multi-pronged approach based on the tube theory, coarse-grained slip-link simulations, and advanced polymeric synthetic and characterization techniques, to confront some of the outstanding problems in entangled polymer rheology. First, we modified simple tube based constitutive equations in extensional rheology and developed functional forms to test the effect of Kuhn segment alignment on a) tube diameter enlargement and b) monomeric friction reduction between subchains. We, then, used these functional forms to model extensional viscosity data for polystyrene (PS) melts and solutions. We demonstrated that the idea of reduction in segmental friction due to Kuhn alignment is successful in explaining the qualitative difference between melts and solutions in extension as revealed by recent experiments on PS. Second, we compiled literature data and used it to develop a universal tube model parameter set and prescribed their values and uncertainties for 1,4-PBd by comparing linear viscoelastic G' and G" mastercurves for 1,4-PBds of various branching architectures. The high frequency transition region of the mastercurves superposed very well for all the 1,4-PBds irrespective of their molecular weight and architecture, indicating universality in high frequency behavior. Therefore, all three parameters of the tube model were extracted from this high frequency transition region alone. Third, we compared predictions of two versions of the tube model, Hierarchical model and BoB model against linear viscoelastic data of blends of 1,4-PBd star and linear melts. The star was carefully synthesized and characterized. We found massive failures of tube models to predict the terminal relaxation behavior of the star/linear blends. In addition, these blends were also tested against a coarse-grained slip-link model, the "Cluster Fixed Slip-link Model (CFSM)" of Schieber and coworkers. The CFSM with only two parameters gave excellent agreement with all experimental data for the blends.
Zhao, Nan; Han, Jing Ginger; Shyu, Chi-Ren; Korkin, Dmitry
2014-01-01
Single nucleotide polymorphisms (SNPs) are among the most common types of genetic variation in complex genetic disorders. A growing number of studies link the functional role of SNPs with the networks and pathways mediated by the disease-associated genes. For example, many non-synonymous missense SNPs (nsSNPs) have been found near or inside the protein-protein interaction (PPI) interfaces. Determining whether such nsSNP will disrupt or preserve a PPI is a challenging task to address, both experimentally and computationally. Here, we present this task as three related classification problems, and develop a new computational method, called the SNP-IN tool (non-synonymous SNP INteraction effect predictor). Our method predicts the effects of nsSNPs on PPIs, given the interaction's structure. It leverages supervised and semi-supervised feature-based classifiers, including our new Random Forest self-learning protocol. The classifiers are trained based on a dataset of comprehensive mutagenesis studies for 151 PPI complexes, with experimentally determined binding affinities of the mutant and wild-type interactions. Three classification problems were considered: (1) a 2-class problem (strengthening/weakening PPI mutations), (2) another 2-class problem (mutations that disrupt/preserve a PPI), and (3) a 3-class classification (detrimental/neutral/beneficial mutation effects). In total, 11 different supervised and semi-supervised classifiers were trained and assessed resulting in a promising performance, with the weighted f-measure ranging from 0.87 for Problem 1 to 0.70 for the most challenging Problem 3. By integrating prediction results of the 2-class classifiers into the 3-class classifier, we further improved its performance for Problem 3. To demonstrate the utility of SNP-IN tool, it was applied to study the nsSNP-induced rewiring of two disease-centered networks. The accurate and balanced performance of SNP-IN tool makes it readily available to study the rewiring of large-scale protein-protein interaction networks, and can be useful for functional annotation of disease-associated SNPs. SNIP-IN tool is freely accessible as a web-server at http://korkinlab.org/snpintool/. PMID:24784581
Predictors of facial attractiveness and health in humans.
Foo, Yong Zhi; Simmons, Leigh W; Rhodes, Gillian
2017-02-03
Facial attractiveness has been suggested to provide signals of biological quality, particularly health, in humans. The attractive traits that have been implicated as signals of biological quality include sexual dimorphism, symmetry, averageness, adiposity, and carotenoid-based skin colour. In this study, we first provide a comprehensive examination of the traits that predict attractiveness. In men, attractiveness was predicted positively by masculinity, symmetry, averageness, and negatively by adiposity. In women, attractiveness was predicted positively by femininity and negatively by adiposity. Skin colour did not predict attractiveness in either sex, suggesting that, despite recent interest in the literature, colour may play limited role in determining attractiveness. Male perceived health was predicted positively by averageness, symmetry, and skin yellowness, and negatively by adiposity. Female perceived health was predicted by femininity. We then examined whether appearance predicted actual health using measures that have been theoretically linked to sexual selection, including immune function, oxidative stress, and semen quality. In women, there was little evidence that female appearance predicted health. In men, we found support for the phenotype-linked fertility hypothesis that male masculinity signalled semen quality. However, we also found a negative relationship between averageness and semen quality. Overall, these results indicate weak links between attractive facial traits and health.
Predictors of facial attractiveness and health in humans
Foo, Yong Zhi; Simmons, Leigh W.; Rhodes, Gillian
2017-01-01
Facial attractiveness has been suggested to provide signals of biological quality, particularly health, in humans. The attractive traits that have been implicated as signals of biological quality include sexual dimorphism, symmetry, averageness, adiposity, and carotenoid-based skin colour. In this study, we first provide a comprehensive examination of the traits that predict attractiveness. In men, attractiveness was predicted positively by masculinity, symmetry, averageness, and negatively by adiposity. In women, attractiveness was predicted positively by femininity and negatively by adiposity. Skin colour did not predict attractiveness in either sex, suggesting that, despite recent interest in the literature, colour may play limited role in determining attractiveness. Male perceived health was predicted positively by averageness, symmetry, and skin yellowness, and negatively by adiposity. Female perceived health was predicted by femininity. We then examined whether appearance predicted actual health using measures that have been theoretically linked to sexual selection, including immune function, oxidative stress, and semen quality. In women, there was little evidence that female appearance predicted health. In men, we found support for the phenotype-linked fertility hypothesis that male masculinity signalled semen quality. However, we also found a negative relationship between averageness and semen quality. Overall, these results indicate weak links between attractive facial traits and health. PMID:28155897
An NCME Instructional Module on Population Invariance in Linking and Equating
ERIC Educational Resources Information Center
Huggins, Anne C.; Penfield, Randall D.
2012-01-01
A goal for any linking or equating of two or more tests is that the linking function be invariant to the population used in conducting the linking or equating. Violations of population invariance in linking and equating jeopardize the fairness and validity of test scores, and pose particular problems for test-based accountability programs that…
Scott, Brandon G; Sanders, Ashley F P; Graham, Rebecca A; Banks, Donice M; Russell, Justin D; Berman, Steven L; Weems, Carl F
2014-10-01
Identity distress involves intense or prolonged upset or worry about personal identity issues including long-term goals, career choice, friendships, sexual orientation and behavior, religion, values and beliefs, and group loyalties. Research suggests that trauma exposure and subsequent PTSD symptoms may negatively impact identity development and psychological adjustment. However, little is known about their specific associations with identity distress and internalizing problems among disaster-exposed adolescents. The purpose of this study was to examine these relationships in a sample of 325 adolescents (60% female; 89% African American) who experienced a major natural disaster and its aftermath. The results indicated that identity distress was positively associated with age, hurricane exposure, PTSD symptoms, and internalizing problems. Linear regression analyses also showed that identity distress was uniquely associated with internalizing symptoms and that there was an indirect effect of hurricane exposure on identity distress via PTSD symptoms. Finally, PTSD symptoms moderated the link between identity distress and internalizing symptoms, with a significant positive slope found for youth with more PTSD symptoms. Findings were generally consistent with previous work and predictions, and add to the extant knowledge about identity distress by providing data on the linkages between disaster exposure, posttraumatic stress and internalizing problems in adolescents.
Integrated modelling requires mass collaboration (Invited)
NASA Astrophysics Data System (ADS)
Moore, R. V.
2009-12-01
The need for sustainable solutions to the world’s problems is self evident; the challenge is to anticipate where, in the environment, economy or society, the proposed solution will have negative consequences. If we failed to realise that the switch to biofuels would have the seemingly obvious result of reduced food production, how much harder will it be to predict the likely impact of policies whose impacts may be more subtle? It has been clear for a long time that models and data will be important tools for assessing the impact of events and the measures for their mitigation. They are an effective way of encapsulating knowledge of a process and using it for prediction. However, most models represent a single or small group of processes. The sustainability challenges that face us now require not just the prediction of a single process but the prediction of how many interacting processes will respond in given circumstances. These processes will not be confined to a single discipline but will often straddle many. For example, the question, “What will be the impact on river water quality of the medical plans for managing a ‘flu pandemic and could they cause a further health hazard?” spans medical planning, the absorption of drugs by the body, the spread of disease, the hydraulic and chemical processes in sewers and sewage treatment works and river water quality. This question nicely reflects the present state of the art. We have models of the processes and standards, such as the Open Modelling Interface (the OpenMI), allow them to be linked together and to datasets. We can therefore answer the question but with the important proviso that we thought to ask it. The next and greater challenge is to deal with the open question, “What are the implications of the medical plans for managing a ‘flu pandemic?”. This implies a system that can make connections that may well not have occurred to us and then evaluate their probable impact. The final touch will be to add, “and are the plans sustainable?” To return to the present, although, it is now possible to ask the first question and obtain an answer through linked modelling; we are still at a very early stage and the associated uncertainties are large. The process of linking and running linked systems is not yet the simple, reliable process needed for widespread uptake. At this point, it is useful to look back over the development process which has taken us from paper maps to GIS and Google Maps; it was the result of tens of thousands of PhD and MSc projects over forty years. During the development of the OpenMI, it was quickly appreciated that to transform integrated modelling from something possible in a research lab to something that had the ease of use and reliability of Google Maps would require a similar process but on a far greater scale; one far larger than any single organisation or state could support. A dramatic change to the research and development process would be needed. Using the OpenMI Association’s strategy as an example, the presentation will describe how through openness, sharing and mass collaboration made possible by inexpensive communications and computing power and adoption of a minimum set of standards, the innovation and enterprise of thousands of individuals across the world can be brought to bear upon the problems.
Frilander, Heikki; Lallukka, Tea; Viikari-Juntura, Eira; Heliövaara, Markku; Solovieva, Svetlana
2016-01-01
Disability retirement causes a significant burden on the society and affects the well-being of individuals. Early health problems as determinants of disability retirement have received little attention. The objective was to study, whether interrupting compulsory military service is an early indicator of disability retirement among Finnish men and whether seeking medical advice during military service increases the risk of all-cause disability retirement and disability retirement due to mental disorders and musculoskeletal diseases. We also looked at secular trends in these associations. We examined a nationally representative sample of 2069 men, who had entered military service during 1967-1996. We linked military service health records with cause-specific register data on disability retirement from 1968 to 2008. Secular trends were explored in three service time strata. We used the Cox regression model to estimate proportional hazard ratios and their 95% confidence intervals. During the follow-up time altogether 140 (6.8%) men retired due to disability, mental disorders being the most common cause. The men who interrupted service had a remarkably higher cumulative incidence of disability retirement (18.9%). The associations between seeking medical advice during military service and all-cause disability retirement were similar across the three service time cohorts (overall hazard ratio 1.40 per one standard deviation of the number of visits; 95% confidence interval 1.26-1.56). Visits due to mental problems predicted disability retirement due to mental disorders in the men who served between 1987 and 1996 and a tendency for a similar cause-specific association was seen for musculoskeletal diseases in the men who served in 1967-1976. In conclusion, health problems-in particular mental problems-during late adolescence are strong determinants of disability retirement. Call-up examinations and military service provide access to the entire age cohort of men, where persons at risk for work disability can be identified and early preventive measures initiated.
Linking the trans-Planckian and information loss problems in black hole physics
NASA Astrophysics Data System (ADS)
Liberati, Stefano; Sindoni, Lorenzo; Sonego, Sebastiano
2010-05-01
The trans-Planckian and information loss problems are usually discussed in the literature as separate issues concerning the nature of Hawking radiation. Here we instead argue that they are intimately linked, and can be understood as “two sides of the same coin” once it is accepted that general relativity is an effective field theory.
ERIC Educational Resources Information Center
Gray, Calonie M. K.; Montgomery, Marilyn J.
2012-01-01
Objectives: This study examined the links between maltreatment, posttraumatic stress symptoms, ethnicity-specific factors (i.e., perceived discrimination, ethnic identity, and ethnic orientation), and alcohol and/or other drug (AOD) problems among adolescent girls. Methods: These relations were examined using archived data from a community sample…
ERIC Educational Resources Information Center
Parade, Stephanie H.; Ridout, Kathryn K.; Seifer, Ronald; Armstrong, David A.; Marsit, Carmen J.; McWilliams, Melissa A.; Tyrka, Audrey R.
2016-01-01
Accumulating evidence suggests that early adversity is linked to methylation of the glucocorticoid receptor (GR) gene, "NR3C1," which is a key regulator of the hypothalamic-pituitary-adrenal axis. Yet no prior work has considered the contribution of methylation of "NR3C1" to emerging behavior problems and psychopathology in…
NASA Technical Reports Server (NTRS)
Manning, Robert M.
1991-01-01
The dynamic and composite nature of propagation impairments that are incurred on Earth-space communications links at frequencies in and above 30/20 GHz Ka band, i.e., rain attenuation, cloud and/or clear air scintillation, etc., combined with the need to counter such degradations after the small link margins have been exceeded, necessitate the use of dynamic statistical identification and prediction processing of the fading signal in order to optimally estimate and predict the levels of each of the deleterious attenuation components. Such requirements are being met in NASA's Advanced Communications Technology Satellite (ACTS) Project by the implementation of optimal processing schemes derived through the use of the Rain Attenuation Prediction Model and nonlinear Markov filtering theory.
Adjoint-Based, Three-Dimensional Error Prediction and Grid Adaptation
NASA Technical Reports Server (NTRS)
Park, Michael A.
2002-01-01
Engineering computational fluid dynamics (CFD) analysis and design applications focus on output functions (e.g., lift, drag). Errors in these output functions are generally unknown and conservatively accurate solutions may be computed. Computable error estimates can offer the possibility to minimize computational work for a prescribed error tolerance. Such an estimate can be computed by solving the flow equations and the linear adjoint problem for the functional of interest. The computational mesh can be modified to minimize the uncertainty of a computed error estimate. This robust mesh-adaptation procedure automatically terminates when the simulation is within a user specified error tolerance. This procedure for estimating and adapting to error in a functional is demonstrated for three-dimensional Euler problems. An adaptive mesh procedure that links to a Computer Aided Design (CAD) surface representation is demonstrated for wing, wing-body, and extruded high lift airfoil configurations. The error estimation and adaptation procedure yielded corrected functions that are as accurate as functions calculated on uniformly refined grids with ten times as many grid points.
Overnight Custody Arrangements, Attachment, and Adjustment Among Very Young Children
Tornello, Samantha L.; Emery, Robert; Rowen, Jenna; Potter, Daniel; Ocker, Bailey; Xu, Yishan
2014-01-01
Large numbers of infants and toddlers have parents who live apart due to separation, divorce, or nonmarital/noncohabiting child-bearing, yet this important topic, especially the controversial issue of frequent overnights with nonresidential parents, is understudied. The authors analyzed data from the Fragile Families and Child Wellbeing Study, a longitudinal investigation of children born to primarily low-income, racial/ethnic minority parents that is representative of 20 U.S. cities with populations over 200,000. Among young children whose parents lived apart, 6.9% of infants (birth to age 1) and 5.3% of toddlers (ages 1 to 3) spent an average of at least 1 overnight per week with their nonresident parent. An additional 6.8% of toddlers spent 35% – 70% of overnights with nonresident parents. Frequent overnights were significantly associated with attachment insecurity among infants, but the relationship was less clear for toddlers. Attachment insecurity predicted adjustment problems at ages 3 and 5, but frequent overnights were not directly linked with adjustment problems at older ages. PMID:25635146
Overnight Custody Arrangements, Attachment, and Adjustment Among Very Young Children.
Tornello, Samantha L; Emery, Robert; Rowen, Jenna; Potter, Daniel; Ocker, Bailey; Xu, Yishan
2013-08-01
Large numbers of infants and toddlers have parents who live apart due to separation, divorce, or nonmarital/noncohabiting child-bearing, yet this important topic, especially the controversial issue of frequent overnights with nonresidential parents, is understudied. The authors analyzed data from the Fragile Families and Child Wellbeing Study, a longitudinal investigation of children born to primarily low-income, racial/ethnic minority parents that is representative of 20 U.S. cities with populations over 200,000. Among young children whose parents lived apart, 6.9% of infants (birth to age 1) and 5.3% of toddlers (ages 1 to 3) spent an average of at least 1 overnight per week with their nonresident parent. An additional 6.8% of toddlers spent 35% - 70% of overnights with nonresident parents. Frequent overnights were significantly associated with attachment insecurity among infants, but the relationship was less clear for toddlers. Attachment insecurity predicted adjustment problems at ages 3 and 5, but frequent overnights were not directly linked with adjustment problems at older ages.
Foraging theory predicts predator-prey energy fluxes.
Brose, U; Ehnes, R B; Rall, B C; Vucic-Pestic, O; Berlow, E L; Scheu, S
2008-09-01
1. In natural communities, populations are linked by feeding interactions that make up complex food webs. The stability of these complex networks is critically dependent on the distribution of energy fluxes across these feeding links. 2. In laboratory experiments with predatory beetles and spiders, we studied the allometric scaling (body-mass dependence) of metabolism and per capita consumption at the level of predator individuals and per link energy fluxes at the level of feeding links. 3. Despite clear power-law scaling of the metabolic and per capita consumption rates with predator body mass, the per link predation rates on individual prey followed hump-shaped relationships with the predator-prey body mass ratios. These results contrast with the current metabolic paradigm, and find better support in foraging theory. 4. This suggests that per link energy fluxes from prey populations to predator individuals peak at intermediate body mass ratios, and total energy fluxes from prey to predator populations decrease monotonically with predator and prey mass. Surprisingly, contrary to predictions of metabolic models, this suggests that for any prey species, the per link and total energy fluxes to its largest predators are smaller than those to predators of intermediate body size. 5. An integration of metabolic and foraging theory may enable a quantitative and predictive understanding of energy flux distributions in natural food webs.
Estimating topological properties of weighted networks from limited information.
Cimini, Giulio; Squartini, Tiziano; Gabrielli, Andrea; Garlaschelli, Diego
2015-10-01
A problem typically encountered when studying complex systems is the limitedness of the information available on their topology, which hinders our understanding of their structure and of the dynamical processes taking place on them. A paramount example is provided by financial networks, whose data are privacy protected: Banks publicly disclose only their aggregate exposure towards other banks, keeping individual exposures towards each single bank secret. Yet, the estimation of systemic risk strongly depends on the detailed structure of the interbank network. The resulting challenge is that of using aggregate information to statistically reconstruct a network and correctly predict its higher-order properties. Standard approaches either generate unrealistically dense networks, or fail to reproduce the observed topology by assigning homogeneous link weights. Here, we develop a reconstruction method, based on statistical mechanics concepts, that makes use of the empirical link density in a highly nontrivial way. Technically, our approach consists in the preliminary estimation of node degrees from empirical node strengths and link density, followed by a maximum-entropy inference based on a combination of empirical strengths and estimated degrees. Our method is successfully tested on the international trade network and the interbank money market, and represents a valuable tool for gaining insights on privacy-protected or partially accessible systems.
Estimating topological properties of weighted networks from limited information
NASA Astrophysics Data System (ADS)
Cimini, Giulio; Squartini, Tiziano; Gabrielli, Andrea; Garlaschelli, Diego
2015-10-01
A problem typically encountered when studying complex systems is the limitedness of the information available on their topology, which hinders our understanding of their structure and of the dynamical processes taking place on them. A paramount example is provided by financial networks, whose data are privacy protected: Banks publicly disclose only their aggregate exposure towards other banks, keeping individual exposures towards each single bank secret. Yet, the estimation of systemic risk strongly depends on the detailed structure of the interbank network. The resulting challenge is that of using aggregate information to statistically reconstruct a network and correctly predict its higher-order properties. Standard approaches either generate unrealistically dense networks, or fail to reproduce the observed topology by assigning homogeneous link weights. Here, we develop a reconstruction method, based on statistical mechanics concepts, that makes use of the empirical link density in a highly nontrivial way. Technically, our approach consists in the preliminary estimation of node degrees from empirical node strengths and link density, followed by a maximum-entropy inference based on a combination of empirical strengths and estimated degrees. Our method is successfully tested on the international trade network and the interbank money market, and represents a valuable tool for gaining insights on privacy-protected or partially accessible systems.
Entropy-based link prediction in weighted networks
NASA Astrophysics Data System (ADS)
Xu, Zhongqi; Pu, Cunlai; Ramiz Sharafat, Rajput; Li, Lunbo; Yang, Jian
2017-01-01
Information entropy has been proved to be an effective tool to quantify the structural importance of complex networks. In the previous work (Xu et al, 2016 \\cite{xu2016}), we measure the contribution of a path in link prediction with information entropy. In this paper, we further quantify the contribution of a path with both path entropy and path weight, and propose a weighted prediction index based on the contributions of paths, namely Weighted Path Entropy (WPE), to improve the prediction accuracy in weighted networks. Empirical experiments on six weighted real-world networks show that WPE achieves higher prediction accuracy than three typical weighted indices.
User manual of the CATSS system (version 1.0) communication analysis tool for space station
NASA Technical Reports Server (NTRS)
Tsang, C. S.; Su, Y. T.; Lindsey, W. C.
1983-01-01
The Communication Analysis Tool for the Space Station (CATSS) is a FORTRAN language software package capable of predicting the communications links performance for the Space Station (SS) communication and tracking (C & T) system. An interactive software package was currently developed to run on the DEC/VAX computers. The CATSS models and evaluates the various C & T links of the SS, which includes the modulation schemes such as Binary-Phase-Shift-Keying (BPSK), BPSK with Direct Sequence Spread Spectrum (PN/BPSK), and M-ary Frequency-Shift-Keying with Frequency Hopping (FH/MFSK). Optical Space Communication link is also included. CATSS is a C & T system engineering tool used to predict and analyze the system performance for different link environment. Identification of system weaknesses is achieved through evaluation of performance with varying system parameters. System tradeoff for different values of system parameters are made based on the performance prediction.
Glass, Kerrie; Flory, Kate; Martin, Amber; Hankin, Benjamin L
2011-03-01
Attention-deficit/hyperactivity disorder (ADHD) is a common child and adolescent disorder that is associated with negative outcomes (e.g., emotional and behavioral problems, substance use) and is often comorbid with Conduct Problems (CP). Research findings are mixed as to whether youth with ADHD alone or comorbid ADHD/CP suffer from low self-esteem. Research has also shown links between low self-esteem and ADHD (alone and with CP) with substance use; yet, no research has examined the links between self-esteem and substance use in adolescents with ADHD and CP. The current study examined the relation between ADHD with and without comorbid CP and self-esteem, and whether self-esteem moderated the relation between ADHD and ADHD/CP with substance use among adolescents. We hypothesized that adolescents with comorbid ADHD/CP would experience lower self-esteem than adolescents with ADHD alone or with neither disorder and that self-esteem would moderate the association between ADHD, CP, and substance use. Participants were 62 adolescents who completed the laboratory-based study with a parent. Results suggested that adolescents with comorbid ADHD and CP had significantly lower self-esteem than adolescents with ADHD alone or neither disorder. Self-esteem was not significantly different for adolescents with ADHD alone versus those in the control group. There was one marginally significant interaction between ADHD and self-esteem predicting substance use, such that individuals with comorbid ADHD/CP who also had low self-esteem tended to use more substances. Results have implications for treatments that target adolescents with ADHD and comorbid CP, as these adolescents are at risk for many deleterious outcomes.
Troxel, Wendy M; Trentacosta, Christopher J; Forbes, Erika E; Campbell, Susan B
2013-02-01
Secure parent-child relationships are implicated in children's self-regulation, including the ability to self-soothe at bedtime. Sleep, in turn, may serve as a pathway linking attachment security with subsequent emotional and behavioral problems in children. We used path analysis to examine the direct relationship between attachment security and maternal reports of sleep problems during toddlerhood and the degree to which sleep serves as a pathway linking attachment with subsequent teacher-reported emotional and behavioral problems. We also examined infant negative emotionality as a vulnerability factor that may potentiate attachment-sleep-adjustment outcomes. Data were drawn from 776 mother-infant dyads participating in the National Institute of Child and Human Development Study of Early Child Care. After statistically adjusting for mother and child characteristics, including child sleep and emotional and behavioral problems at 24 months, we found no evidence for a statistically significant direct path between attachment security and sleep problems at 36 months; however, there was a direct relationship between sleep problems at 36 months and internalizing problems at 54 months. Path models that examined the moderating influence of infant negative emotionality demonstrated significant direct relationships between attachment security and toddler sleep problems and between sleep problems and subsequent emotional and behavioral problems, but only among children characterized by high negative emotionality at 6 months. In addition, among this subset, there was a significant indirect path between attachment and internalizing problems through sleep problems. These longitudinal findings implicate sleep as one critical pathway linking attachment security with adjustment difficulties, particularly among temperamentally vulnerable children. PsycINFO Database Record (c) 2013 APA, all rights reserved.
Troxel, Wendy M.; Trentacosta, Christopher J.; Forbes, Erika E.; Campbell, Susan B.
2013-01-01
Secure parent-child relationships are implicated in children’s self-regulation, including the ability to self-soothe at bedtime. Sleep, in turn, may serve as a pathway linking attachment security with subsequent emotional and behavioral problems in children. We used path analysis to examine the direct relationship between attachment security and maternal-reports of sleep problems during toddlerhood, and the degree to which sleep serves as a pathway linking attachment with subsequent teacher-reported emotional and behavioral problems. We also examined infant negative emotionality as a vulnerability factor that may potentiate attachment-sleep-adjustment outcomes. Data were drawn from 776 mother-infant dyads participating in the NICHD Study of Early Child Care (SECC). In the full sample, after statistically adjusting for mother and child characteristics, including child sleep and emotional and behavioral problems at 24 months, we did not find evidence for a statistically significant direct path between attachment security and sleep problems at 36 months; however, there was a direct relationship between sleep problems at 36 months and internalizing problems at 54 months. Path models that examined the moderating influence of infant negative emotionality demonstrated significant direct relationships between attachment security and toddler sleep problems, and sleep problems and subsequent emotional and behavioral problems, but only among children characterized by high negative emotionality at 6 months of age. In addition, among this subset, there was a significant indirect path between attachment and internalizing problems through sleep problems. These longitudinal findings implicate sleep as one critical pathway linking attachment security with adjustment difficulties, particularly among temperamentally vulnerable children. PMID:23421840
Spindle Thermal Error Optimization Modeling of a Five-axis Machine Tool
NASA Astrophysics Data System (ADS)
Guo, Qianjian; Fan, Shuo; Xu, Rufeng; Cheng, Xiang; Zhao, Guoyong; Yang, Jianguo
2017-05-01
Aiming at the problem of low machining accuracy and uncontrollable thermal errors of NC machine tools, spindle thermal error measurement, modeling and compensation of a two turntable five-axis machine tool are researched. Measurement experiment of heat sources and thermal errors are carried out, and GRA(grey relational analysis) method is introduced into the selection of temperature variables used for thermal error modeling. In order to analyze the influence of different heat sources on spindle thermal errors, an ANN (artificial neural network) model is presented, and ABC(artificial bee colony) algorithm is introduced to train the link weights of ANN, a new ABC-NN(Artificial bee colony-based neural network) modeling method is proposed and used in the prediction of spindle thermal errors. In order to test the prediction performance of ABC-NN model, an experiment system is developed, the prediction results of LSR (least squares regression), ANN and ABC-NN are compared with the measurement results of spindle thermal errors. Experiment results show that the prediction accuracy of ABC-NN model is higher than LSR and ANN, and the residual error is smaller than 3 μm, the new modeling method is feasible. The proposed research provides instruction to compensate thermal errors and improve machining accuracy of NC machine tools.
Decision-making, sensitivity to reward, and attrition in weight-management
Koritzky, Gilly; Dieterle, Camille; Rice, Chantelle; Jordan, Katie; Bechara, Antoine
2014-01-01
Objective Attrition is a common problem in weight-management. Understanding the risk factors for attrition should enhance professionals’ ability to increase completion rates and improve health outcomes for more individuals. We propose a model that draws upon neuropsychological knowledge on reward-sensitivity in obesity and overeating to predict attrition. Design & Methods 52 participants in a weight-management program completed a complex decision-making task.Decision-making characteristics – including sensitivity to reward – were further estimated using a quantitative model. Impulsivity and risk-taking measures were also administered. Results Consistent with the hypothesis that sensitivity to reward predicted attrition, program dropouts had higher sensitivity to reward than completers (p < 0.03). No differences were observed between completers and dropouts in initial BMI, age, employment status, or the number of prior weight-loss attempts (p ≥ 0.07). Completers had a slightly higher education level than dropouts, but its inclusion in the model did not increase predictive power. Impulsivity, delay of gratification, and risk-taking did not predict attrition, either. Conclusions Findings link attrition in weight-management to the neural mechanisms associated with reward-seeking and related influences on decision-making. Individual differences in the magnitude of response elicited by rewards may account for the relative difficulty experienced by dieters in adhering to treatment. PMID:24771588
Testable solution of the cosmological constant and coincidence problems
NASA Astrophysics Data System (ADS)
Shaw, Douglas J.; Barrow, John D.
2011-02-01
We present a new solution to the cosmological constant (CC) and coincidence problems in which the observed value of the CC, Λ, is linked to other observable properties of the Universe. This is achieved by promoting the CC from a parameter that must be specified, to a field that can take many possible values. The observed value of Λ≈(9.3Gyrs)-2 [≈10-120 in Planck units] is determined by a new constraint equation which follows from the application of a causally restricted variation principle. When applied to our visible Universe, the model makes a testable prediction for the dimensionless spatial curvature of Ωk0=-0.0056(ζb/0.5), where ζb˜1/2 is a QCD parameter. Requiring that a classical history exist, our model determines the probability of observing a given Λ. The observed CC value, which we successfully predict, is typical within our model even before the effects of anthropic selection are included. When anthropic selection effects are accounted for, we find that the observed coincidence between tΛ=Λ-1/2 and the age of the Universe, tU, is a typical occurrence in our model. In contrast to multiverse explanations of the CC problems, our solution is independent of the choice of a prior weighting of different Λ values and does not rely on anthropic selection effects. Our model includes no unnatural small parameters and does not require the introduction of new dynamical scalar fields or modifications to general relativity, and it can be tested by astronomical observations in the near future.
An Optimal Schedule for Urban Road Network Repair Based on the Greedy Algorithm
Lu, Guangquan; Xiong, Ying; Wang, Yunpeng
2016-01-01
The schedule of urban road network recovery caused by rainstorms, snow, and other bad weather conditions, traffic incidents, and other daily events is essential. However, limited studies have been conducted to investigate this problem. We fill this research gap by proposing an optimal schedule for urban road network repair with limited repair resources based on the greedy algorithm. Critical links will be given priority in repair according to the basic concept of the greedy algorithm. In this study, the link whose restoration produces the ratio of the system-wide travel time of the current network to the worst network is the minimum. We define such a link as the critical link for the current network. We will re-evaluate the importance of damaged links after each repair process is completed. That is, the critical link ranking will be changed along with the repair process because of the interaction among links. We repair the most critical link for the specific network state based on the greedy algorithm to obtain the optimal schedule. The algorithm can still quickly obtain an optimal schedule even if the scale of the road network is large because the greedy algorithm can reduce computational complexity. We prove that the problem can obtain the optimal solution using the greedy algorithm in theory. The algorithm is also demonstrated in the Sioux Falls network. The problem discussed in this paper is highly significant in dealing with urban road network restoration. PMID:27768732
Evaluation of Hierarchical Clustering Algorithms for Document Datasets
2002-06-03
link, complete-link, and group average ( UPGMA )) and a new set of merging criteria derived from the six partitional criterion functions. Overall, we...used the single-link, complete-link, and UPGMA schemes, as well as, the various partitional criterion functions described in Section 3.1. The single-link...other (complete-link approach). The UPGMA scheme [16] (also known as group average) overcomes these problems by measuring the similarity of two clusters