Discovering alignment relations with Graph Convolutional Networks: A biomedical case study

Knowledge graphs are freely aggregated, published, and edited in the Web of data, and thus may overlap. Hence, a key task resides in aligning (or matching) their content. This task encompasses the identification, within an aggregated knowledge graph, of nodes that are equivalent, more specific, or weakly related. In this article, we propose to match nodes within a knowledge graph by (i) learning node embeddings with Graph Convolutional Networks such that similar nodes have low distances in the embedding space, and (ii) clustering nodes based on their embeddings, in order to suggest alignment relations between nodes of a same cluster. We conducted experiments with this approach on the real world application of aligning knowledge in the field of pharmacogenomics, which motivated our study. We particularly investigated the interplay between domain knowledge and GCN models with the two following focuses. First, we applied inference rules associated with domain knowledge, independently or combined, before learning node embeddings, and we measured the improvements in matching results. Second, while our GCN model is agnostic to the exact alignment relations (e.g., equivalence, weak similarity), we observed that distances in the embedding space are coherent with the “strength” of these different relations (e.g., smaller distances for equivalences), letting us considering clustering and distances in the embedding space as a means to suggest alignment relations in our case study.

Individual Differences in Romantic Attachment

In the 1980s, psychologists extended attachment theory into the domain of adult romantic bonds by proposing that romantic love can be conceptualized as a process of becoming attached ( Hazan & Shaver, 1987 ). From this perspective, individuals differ in two primary attachment dimensions: anxiety, the extent to which they worry about abandonment in their romantic relationships, and avoidance, the extent to which they are uncomfortable with interdependence and closeness. Research suggests that people perceive the rearing environment as a primary cause of people’s romantic attachment styles ( Tillman et al., 2008 ). If it is, family members should be similar in attachment-related anxiety and avoidance. To test this idea, we collected romantic attachment data on 965 US college students and the family members they nominated (205 siblings, 245 mothers, and 182 fathers). The students and family members in our sample showed negligible-to-weak resemblance in attachment-related anxiety and avoidance. Because previous studies have shown substantial similarity between identical twins and weak similarity between fraternal twins in romantic attachment styles, our data reinforce the possibility that nonshared environmental influences (such as individuals’ specific relationship histories) and genetic influences are the primary sources of individual differences in attachment-related anxiety and avoidance.

Generalized Schur–Nevanlinna functions and their realizations

Pontryagin space operator valued generalized Schur functions and generalized Nevanlinna functions are investigated by using discrete-time systems, or operator colligations, and state space realizations. It is shown that generalized Schur functions have strong radial limit values almost everywhere on the unit circle. These limit values are contractive with respect to the indefinite inner product, which allows one to generalize the notion of an inner function to Pontryagin space operator valued setting. Transfer functions of self-adjoint systems such that their state spaces are Pontryagin spaces, are generalized Nevanlinna functions, and symmetric generalized Schur functions can be realized as transfer functions of self-adjoint systems with Kreĭn spaces as state spaces. A criterion when a symmetric generalized Schur function is also a generalized Nevanlinna function is given. The criterion involves the negative index of the weak similarity mapping between an optimal minimal realization and its dual. In the special case corresponding to the generalization of an inner function, a concrete model for the weak similarity mapping can be obtained by using the canonical realizations.

Floristic diversity of woody stands of the Sudano Guinean Savannah of Mbam and Djerem National Park (PNMD), Cameroon

The combined effect of climatic deterioration and anthropogenic pressure has caused a gradual degradation of the natural resources of the Mbam and Djerem National Park. This phenomenon has not spared the woody stratum which constitutes in this region the main source of forage in the dry season. The rehabilitation of these ecosystems necessarily requires precise ecological knowledge, hence the interest in making a diagnosis of the floristic diversity of the woody stratum. The dendrometric sampling method was used for this study carried out in Mbam and Djerem National Park. This inventory consisted in systematically identifying all the woody species by height class in 3 sites according to factor gradients. This method made it possible to inventory a total of 1,596 trees, divided into 45 species belonging to 24 families. Statistical processing of data obtained in the field shows that the flora is dominated by the family of Euphorbiaceae, Combretaceae, Fabaceae and Rubiaceae group together the maximum of species with, respectively, 7 and 4 listed for the others. The richness of flora is more important in Kpayere which presents a weak similarity with Debiro.

Stage 1 Registered Report Manuscript - Transcriptional Correlates of Savings Memory: Is Forgetting Due to Decay or Retrieval Failure?

[[This is a Stage 1 Registered Report manuscript. The project was submitted for review to eNeuro. Upon revision and acceptance, this version of the manuscript was pre-registered on the OSF (9/11/2019, https://osf.io/fqh8j) (but due to an oversight not posted as a preprint until July 2020). A Stage 2 manuscript is now posted as a pre-print (https://psyarxiv.com/h59jv) and is under review at eNeuro. A link to the final Stage 2 manuscript will be added when available.]]There is fundamental debate about the nature of forgetting: some have argued that it represents the decay of the memory trace, others that the memory trace persists but becomes inaccessible due to retrieval failure. These different accounts of forgetting make different predictions about savings memory, the rapid re-learning of seemingly forgotten information. If forgetting is due to decay then savings requires re-encoding and should thus involve the same mechanisms as initial learning. If forgetting is due to retrieval-failure then savings should be mechanistically distinct from encoding. In this registered report we conducted a pre-registered and rigorous test between these accounts of forgetting. Specifically, we used microarray to characterize the transcriptional correlates of a new memory (1 day from training), a forgotten memory (8 days from training), and a savings memory (8 days from training but with a reminder on day 7 to evoke a long-term savings memory) for sensitization in Aplysia californica (n = 8 samples/group). We find that the transcriptional correlates of savings are [highly similar / somewhat similar / unique] relative to new (1-day-old) memories. Specifically, savings memory and a new memory share [X] of [Y] regulated transcripts, show [strong / moderate / weak] similarity in sets of regulated transcripts, and show [r] correlation in regulated gene expression, which is [substantially / somewhat / not at all] stronger than at forgetting. Overall, our results suggest that forgetting represents [decay / retrieval-failure / mixed mechanisms].

A new species of Sympherobius Banks (Neuroptera: Hemerobiidae) from the late Eocene Rovno amber

Sympherobius irinae sp. nov. (Neuroptera: Hemerobiidae: Sympherobiinae) is described from the late Eocene Rovno amber, Ukraine. It differs from other species of the genus by small details in the forewing venation: (1) crossvein 3rp1-rp2 is not strongly shifted distally relative to neighboring crossveins in the third gradate series, and (2) the humeral veinlet has only two branches. All four late Eocene species form a distinctive species group, which is named here the completus species group, distinguished from other species of the genus by the presence of the crossvein 3rp2-rp3 in the forewing in distal position, connecting RP2 and RP3. The neuropteran assemblages of the Bembridge Marls and succinites (particularly Baltic and Rovno ambers) are briefly compared. The assemblages of some families are relatively similar, but there are obvious differences in others. It is impossible to draw conclusions about the age of Baltic or Rovno ambers based on this weak similarity.

On a Continuum Model for Avalanche Flow and Its Simplified Variants

Mathematical models of different degrees of complexity, describing the motion of a snow avalanche along a path with given center line and spatially varying width, are formulated and compared. The most complete model integrates the balance equations for mass and momentum over the cross-section and achieves closure through an entrainment function based on shock theory and a modified Voellmy bed friction law where the Coulombic contribution to the bed shear stress is limited by the shear strength of the snow cover. A simplified model results from integrating these balance equations over the (time-dependent) length of the flow and postulating weak similarity of the evolving avalanche shape. On path segments of constant inclination, it can be solved for the flow depth and speed of the front in closed form in terms of the imaginary error function. Finally, the very simplest model assumes constant flow height and length. On an inclined plane, the evolution of flow depth and velocity predicted by the simplified model are close to those from the full model without entrainment and with corresponding parameters, but the simplest model with constant flow depth predicts much higher velocity values. If the friction coefficient is varied in the full model with entrainment, there can be non-monotonous behavior due to the non-linear interplay between entrainment and the limitation on the Coulomb friction.