43 research outputs found
Sparsely Aggregated Convolutional Networks
We explore a key architectural aspect of deep convolutional neural networks:
the pattern of internal skip connections used to aggregate outputs of earlier
layers for consumption by deeper layers. Such aggregation is critical to
facilitate training of very deep networks in an end-to-end manner. This is a
primary reason for the widespread adoption of residual networks, which
aggregate outputs via cumulative summation. While subsequent works investigate
alternative aggregation operations (e.g. concatenation), we focus on an
orthogonal question: which outputs to aggregate at a particular point in the
network. We propose a new internal connection structure which aggregates only a
sparse set of previous outputs at any given depth. Our experiments demonstrate
this simple design change offers superior performance with fewer parameters and
lower computational requirements. Moreover, we show that sparse aggregation
allows networks to scale more robustly to 1000+ layers, thereby opening future
avenues for training long-running visual processes.Comment: Accepted to ECCV 201
PolyDiffuse: Polygonal Shape Reconstruction via Guided Set Diffusion Models
This paper presents PolyDiffuse, a novel structured reconstruction algorithm
that transforms visual sensor data into polygonal shapes with Diffusion Models
(DM), an emerging machinery amid exploding generative AI, while formulating
reconstruction as a generation process conditioned on sensor data. The task of
structured reconstruction poses two fundamental challenges to DM: 1) A
structured geometry is a ``set'' (e.g., a set of polygons for a floorplan
geometry), where a sample of elements has different but equivalent
representations, making the denoising highly ambiguous; and 2) A
``reconstruction'' task has a single solution, where an initial noise needs to
be chosen carefully, while any initial noise works for a generation task. Our
technical contribution is the introduction of a Guided Set Diffusion Model
where 1) the forward diffusion process learns guidance networks to control
noise injection so that one representation of a sample remains distinct from
its other permutation variants, thus resolving denoising ambiguity; and 2) the
reverse denoising process reconstructs polygonal shapes, initialized and
directed by the guidance networks, as a conditional generation process subject
to the sensor data. We have evaluated our approach for reconstructing two types
of polygonal shapes: floorplan as a set of polygons and HD map for autonomous
cars as a set of polylines. Through extensive experiments on standard
benchmarks, we demonstrate that PolyDiffuse significantly advances the current
state of the art and enables broader practical applications.Comment: Project page: https://poly-diffuse.github.io
Characterizing Adversarial Examples Based on Spatial Consistency Information for Semantic Segmentation
Deep Neural Networks (DNNs) have been widely applied in various recognition
tasks. However, recently DNNs have been shown to be vulnerable against
adversarial examples, which can mislead DNNs to make arbitrary incorrect
predictions. While adversarial examples are well studied in classification
tasks, other learning problems may have different properties. For instance,
semantic segmentation requires additional components such as dilated
convolutions and multiscale processing. In this paper, we aim to characterize
adversarial examples based on spatial context information in semantic
segmentation. We observe that spatial consistency information can be
potentially leveraged to detect adversarial examples robustly even when a
strong adaptive attacker has access to the model and detection strategies. We
also show that adversarial examples based on attacks considered within the
paper barely transfer among models, even though transferability is common in
classification. Our observations shed new light on developing adversarial
attacks and defenses to better understand the vulnerabilities of DNNs.Comment: Accepted to ECCV 201
Case Report: Diabetes in Chinese Bloom Syndrome
Bloom syndrome (BS) is a rare autosomal recessive disorder that causes several endocrine abnormalities. So far, only one BS pedigree, without diabetes, has been reported in the Chinese population. We presented the first case of BS with diabetes in the Chinese population and explored the clinical spectrum associated with endocrine. Possible molecular mechanisms were also investigated. Our study indicated that BS may be one rare cause of diabetes in the Chinese population. We also found a new pathogenic sequence variant in BLM (BLM RecQ like helicase gene)(NM_000057.4) c.692T>G, which may expand the spectrum of BLM variants
Controllable ingestion and release of guest components driven by interfacial molecular orientation of host liquid crystal droplets
Controllable construction and manipulation of artificial multi-compartmental structures are crucial in understanding and imitating smart molecular elements such as biological cells and on-demand delivery systems. Here, we report a liquid crystal droplet (LCD) based three-dimensional system for controllable and reversible ingestion and release of guest aqueous droplets (GADs). Induced by interfacial thermodynamic fluctuation and internal topological defect, microscale LCDs with perpendicular anchoring condition at the interface would spontaneously ingest external components from the surroundings and transform them as radially assembled tiny GADs inside LCDs. Landau–de Gennes free-energy model is applied to describe and explain the assembly dynamics and morphologies of these tiny GADs, which presents a good agreement with experimental observations. Furthermore, the release of these ingested GADs can be actively triggered by changing the anchoring conditions at the interface of LCDs. Since those ingestion and release processes are controllable and happen very gently at room temperature and neutral pH environment without extra energy input, these microscale LCDs are very prospective to provide a unique and viable route for constructing hierarchical 3D structures with tunable components and compartments
Comprehensive multi-omics integration identifies differentially active enhancers during human brain development with clinical relevance
Abstract Background Non-coding regulatory elements (NCREs), such as enhancers, play a crucial role in gene regulation, and genetic aberrations in NCREs can lead to human disease, including brain disorders. The human brain is a complex organ that is susceptible to numerous disorders; many of these are caused by genetic changes, but a multitude remain currently unexplained. Understanding NCREs acting during brain development has the potential to shed light on previously unrecognized genetic causes of human brain disease. Despite immense community-wide efforts to understand the role of the non-coding genome and NCREs, annotating functional NCREs remains challenging. Methods Here we performed an integrative computational analysis of virtually all currently available epigenome data sets related to human fetal brain. Results Our in-depth analysis unravels 39,709 differentially active enhancers (DAEs) that show dynamic epigenomic rearrangement during early stages of human brain development, indicating likely biological function. Many of these DAEs are linked to clinically relevant genes, and functional validation of selected DAEs in cell models and zebrafish confirms their role in gene regulation. Compared to enhancers without dynamic epigenomic rearrangement, DAEs are subjected to higher sequence constraints in humans, have distinct sequence characteristics and are bound by a distinct transcription factor landscape. DAEs are enriched for GWAS loci for brain-related traits and for genetic variation found in individuals with neurodevelopmental disorders, including autism. Conclusion This compendium of high-confidence enhancers will assist in deciphering the mechanism behind developmental genetics of human brain and will be relevant to uncover missing heritability in human genetic brain disorders