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Landmark detection in 2D bioimages for geometric morphometrics: a multi-resolution tree-based approach
The detection of anatomical landmarks in bioimages is a necessary but tedious step for geometric morphometrics studies in many research domains. We propose variants of a multi-resolution tree-based approach to speed-up the detection of landmarks in bioimages. We extensively evaluate our method variants on three different datasets (cephalometric, zebrafish, and drosophila images). We identify the key method parameters (notably the multi-resolution) and report results with respect to human ground truths and existing methods. Our method achieves recognition performances competitive with current existing approaches while being generic and fast. The algorithms are integrated in the open-source Cytomine software and we provide parameter configuration guidelines so that they can be easily exploited by end-users. Finally, datasets are readily available through a Cytomine server to foster future research
Probabilistic models of information retrieval based on measuring the divergence from randomness
We introduce and create a framework for deriving probabilistic models of Information Retrieval. The models are nonparametric models of IR obtained in the language model approach. We derive term-weighting models by measuring the divergence of the actual term distribution from that obtained under a random process. Among the random processes we study the binomial distribution and Bose--Einstein statistics. We define two types of term frequency normalization for tuning term weights in the document--query matching process. The first normalization assumes that documents have the same length and measures the information gain with the observed term once it has been accepted as a good descriptor of the observed document. The second normalization is related to the document length and to other statistics. These two normalization methods are applied to the basic models in succession to obtain weighting formulae. Results show that our framework produces different nonparametric models forming baseline alternatives to the standard tf-idf model
Distorted body representations in healthy cognition
Delusions and misperceptions about the body are a conspicuous feature of numerous neurological and psychiatric conditions. In stark contrast to such pathological cases, the immediacy and familiarity of our ordinary experience of our body can make it seem as if our representation of our body is highly accurate, even infallible. Recent research has begun to demonstrate, however, that large and systematic distortions of body representation are a normal part of healthy cognition. Here, I will describe this research, focusing on distortions of body representations underlying tactile distance perception and position sense. I will also discuss evidence for distortions of higher-order body representations, such as the conscious body image. Finally, I will end with a discussion of the potential relations among different body representations and their distortions
Maternal Drinking During Pregnancy: Attention and Short-Term Memory in 14-Year-Old Offspring—A Longitudinal Prospective Study
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66151/1/j.1530-0277.1994.tb00904.x.pd
Anisotropic Radial Layout for Visualizing Centrality and Structure in Graphs
This paper presents a novel method for layout of undirected graphs, where
nodes (vertices) are constrained to lie on a set of nested, simple, closed
curves. Such a layout is useful to simultaneously display the structural
centrality and vertex distance information for graphs in many domains,
including social networks. Closed curves are a more general constraint than the
previously proposed circles, and afford our method more flexibility to preserve
vertex relationships compared to existing radial layout methods. The proposed
approach modifies the multidimensional scaling (MDS) stress to include the
estimation of a vertex depth or centrality field as well as a term that
penalizes discord between structural centrality of vertices and their alignment
with this carefully estimated field. We also propose a visualization strategy
for the proposed layout and demonstrate its effectiveness using three social
network datasets.Comment: Appears in the Proceedings of the 25th International Symposium on
Graph Drawing and Network Visualization (GD 2017
Do Not Mask What You Do Not Need to Mask: a Parser-Free Virtual Try-On
The 2D virtual try-on task has recently attracted a great interest from the
research community, for its direct potential applications in online shopping as
well as for its inherent and non-addressed scientific challenges. This task
requires fitting an in-shop cloth image on the image of a person, which is
highly challenging because it involves cloth warping, image compositing, and
synthesizing. Casting virtual try-on into a supervised task faces a difficulty:
available datasets are composed of pairs of pictures (cloth, person wearing the
cloth). Thus, we have no access to ground-truth when the cloth on the person
changes. State-of-the-art models solve this by masking the cloth information on
the person with both a human parser and a pose estimator. Then, image synthesis
modules are trained to reconstruct the person image from the masked person
image and the cloth image. This procedure has several caveats: firstly, human
parsers are prone to errors; secondly, it is a costly pre-processing step,
which also has to be applied at inference time; finally, it makes the task
harder than it is since the mask covers information that should be kept such as
hands or accessories. In this paper, we propose a novel student-teacher
paradigm where the teacher is trained in the standard way (reconstruction)
before guiding the student to focus on the initial task (changing the cloth).
The student additionally learns from an adversarial loss, which pushes it to
follow the distribution of the real images. Consequently, the student exploits
information that is masked to the teacher. A student trained without the
adversarial loss would not use this information. Also, getting rid of both
human parser and pose estimator at inference time allows obtaining a real-time
virtual try-on.Comment: Accepted at ECCV 2020. arXiv admin note: text overlap with
arXiv:1906.0134
Chemical signals act as the main reproductive barrier between sister and mimetic Heliconius butterflies.
Colour pattern is the main trait that drives mate recognition between Heliconius species that are phylogenetically close. However, when this cue is compromised such as in cases of mimetic, sympatric and closely related species, alternative mating signals must evolve to ensure reproductive isolation and species integrity. The closely related species Heliconius melpomene malleti and H. timareta florencia occur in the same geographical region, and despite being co-mimics, they display strong reproductive isolation. In order to test which cues differ between species, and potentially contribute to reproductive isolation, we quantified differences in the wing phenotype and the male chemical profile. As expected, the wing colour pattern was indistinguishable between the two species, while the chemical profile of the androconial and genital males' extracts showed marked differences. We then conducted behavioural experiments to study the importance of these signals in mate recognition by females. In agreement with our previous results, we found that chemical blends and not wing colour pattern drive the preference of females for conspecific males. Also, experiments with hybrid males and females suggested an important genetic component for both chemical production and preference. Altogether, these results suggest that chemicals are the major reproductive barrier opposing gene flow between these two sister and co-mimic species
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