StarNet: towards Weakly Supervised Few-Shot Object Detection

Few-shot detection and classification have advanced significantly in recent years. Yet, detection approaches require strong annotation (bounding boxes) both for pre-training and for adaptation to novel classes, and classification approaches rarely provide localization of objects in the scene. In this paper, we introduce StarNet - a few-shot model featuring an end-to-end differentiable non-parametric star-model detection and classification head. Through this head, the backbone is meta-trained using only image-level labels to produce good features for jointly localizing and classifying previously unseen categories of few-shot test tasks using a star-model that geometrically matches between the query and support images (to find corresponding object instances). Being a few-shot detector, StarNet does not require any bounding box annotations, neither during pre-training nor for novel classes adaptation. It can thus be applied to the previously unexplored and challenging task of Weakly Supervised Few-Shot Object Detection (WS-FSOD), where it attains significant improvements over the baselines. In addition, StarNet shows significant gains on few-shot classification benchmarks that are less cropped around the objects (where object localization is key)

A genome-wide association study of anorexia nervosa

Anorexia nervosa (AN) is a complex and heritable eating disorder characterized by dangerously low body weight. Neither candidate gene studies nor an initial genome wide association study (GWAS) have yielded significant and replicated results. We performed a GWAS in 2,907 cases with AN from 14 countries (15 sites) and 14,860 ancestrally matched controls as part of the Genetic Consortium for AN (GCAN) and the Wellcome Trust Case Control Consortium 3 (WTCCC3). Individual association analyses were conducted in each stratum and meta-analyzed across all 15 discovery datasets. Seventy-six (72 independent) SNPs were taken forward for in silico (two datasets) or de novo (13 datasets) replication genotyping in 2,677 independent AN cases and 8,629 European ancestry controls along with 458 AN cases and 421 controls from Japan. The final global meta-analysis across discovery and replication datasets comprised 5,551 AN cases and 21,080 controls. AN subtype analyses (1,606 AN restricting; 1,445 AN binge-purge) were performed. No findings reached genome-wide significance. Two intronic variants were suggestively associated: rs9839776 (P=3.01×10−7) in SOX2OT and rs17030795 (P=5.84×10−6) in PPP3CA. Two additional signals were specific to Europeans: rs1523921 (P=5.76×10−6) between CUL3 and FAM124B and rs1886797 (P=8.05×10−6) near SPATA13. Comparing discovery to replication results, 76% of the effects were in the same direction, an observation highly unlikely to be due to chance (P= 4×10−6), strongly suggesting that true findings exist but that our sample, the largest yet reported, was underpowered for their detection. The accrual of large genotyped AN case-control samples should be an immediate priority for the field

A genome-wide association study of anorexia nervosa suggests a risk locus implicated in dysregulated leptin signaling

J. Kaprio, A. Palotie, A. Raevuori-Helkamaa ja S. Ripatti ovat työryhmän Eating Disorders Working Group of the Psychiatric Genomics Consortium jäseniä. Erratum in: Sci Rep. 2017 Aug 21;7(1):8379, doi: 10.1038/s41598-017-06409-3We conducted a genome-wide association study (GWAS) of anorexia nervosa (AN) using a stringently defined phenotype. Analysis of phenotypic variability led to the identification of a specific genetic risk factor that approached genome-wide significance (rs929626 in EBF1 (Early B-Cell Factor 1); P = 2.04 x 10(-7); OR = 0.7; 95% confidence interval (CI) = 0.61-0.8) with independent replication (P = 0.04), suggesting a variant-mediated dysregulation of leptin signaling may play a role in AN. Multiple SNPs in LD with the variant support the nominal association. This demonstrates that although the clinical and etiologic heterogeneity of AN is universally recognized, further careful sub-typing of cases may provide more precise genomic signals. In this study, through a refinement of the phenotype spectrum of AN, we present a replicable GWAS signal that is nominally associated with AN, highlighting a potentially important candidate locus for further investigation.Peer reviewe

Common Genetic Variation And Age at Onset Of Anorexia Nervosa

Background Genetics and biology may influence the age at onset of anorexia nervosa (AN). The aims of this study were to determine whether common genetic variation contributes to AN age at onset and to investigate the genetic associations between age at onset of AN and age at menarche. Methods A secondary analysis of the Psychiatric Genomics Consortium genome-wide association study (GWAS) of AN was performed which included 9,335 cases and 31,981 screened controls, all from European ancestries. We conducted GWASs of age at onset, early-onset AN (< 13 years), and typical-onset AN, and genetic correlation, genetic risk score, and Mendelian randomization analyses. Results Two loci were genome-wide significant in the typical-onset AN GWAS. Heritability estimates (SNP-h2) were 0.01-0.04 for age at onset, 0.16-0.25 for early-onset AN, and 0.17-0.25 for typical-onset AN. Early- and typical-onset AN showed distinct genetic correlation patterns with putative risk factors for AN. Specifically, early-onset AN was significantly genetically correlated with younger age at menarche, and typical-onset AN was significantly negatively genetically correlated with anthropometric traits. Genetic risk scores for age at onset and early-onset AN estimated from independent GWASs significantly predicted age at onset. Mendelian randomization analysis suggested a causal link between younger age at menarche and early-onset AN. Conclusions Our results provide evidence consistent with a common variant genetic basis for age at onset and implicate biological pathways regulating menarche and reproduction.Peer reviewe

Shared genetic risk between eating disorder- and substance-use-related phenotypes:Evidence from genome-wide association studies

First published: 16 February 202

Genomic Relationships, Novel Loci, and Pleiotropic Mechanisms across Eight Psychiatric Disorders

Genetic influences on psychiatric disorders transcend diagnostic boundaries, suggesting substantial pleiotropy of contributing loci. However, the nature and mechanisms of these pleiotropic effects remain unclear. We performed analyses of 232,964 cases and 494,162 controls from genome-wide studies of anorexia nervosa, attention-deficit/hyper-activity disorder, autism spectrum disorder, bipolar disorder, major depression, obsessive-compulsive disorder, schizophrenia, and Tourette syndrome. Genetic correlation analyses revealed a meaningful structure within the eight disorders, identifying three groups of inter-related disorders. Meta-analysis across these eight disorders detected 109 loci associated with at least two psychiatric disorders, including 23 loci with pleiotropic effects on four or more disorders and 11 loci with antagonistic effects on multiple disorders. The pleiotropic loci are located within genes that show heightened expression in the brain throughout the lifespan, beginning prenatally in the second trimester, and play prominent roles in neurodevelopmental processes. These findings have important implications for psychiatric nosology, drug development, and risk prediction.Peer reviewe

Dissecting the Shared Genetic Architecture of Suicide Attempt, Psychiatric Disorders, and Known Risk Factors

Background Suicide is a leading cause of death worldwide, and nonfatal suicide attempts, which occur far more frequently, are a major source of disability and social and economic burden. Both have substantial genetic etiology, which is partially shared and partially distinct from that of related psychiatric disorders. Methods We conducted a genome-wide association study (GWAS) of 29,782 suicide attempt (SA) cases and 519,961 controls in the International Suicide Genetics Consortium (ISGC). The GWAS of SA was conditioned on psychiatric disorders using GWAS summary statistics via multitrait-based conditional and joint analysis, to remove genetic effects on SA mediated by psychiatric disorders. We investigated the shared and divergent genetic architectures of SA, psychiatric disorders, and other known risk factors. Results Two loci reached genome-wide significance for SA: the major histocompatibility complex and an intergenic locus on chromosome 7, the latter of which remained associated with SA after conditioning on psychiatric disorders and replicated in an independent cohort from the Million Veteran Program. This locus has been implicated in risk-taking behavior, smoking, and insomnia. SA showed strong genetic correlation with psychiatric disorders, particularly major depression, and also with smoking, pain, risk-taking behavior, sleep disturbances, lower educational attainment, reproductive traits, lower socioeconomic status, and poorer general health. After conditioning on psychiatric disorders, the genetic correlations between SA and psychiatric disorders decreased, whereas those with nonpsychiatric traits remained largely unchanged. Conclusions Our results identify a risk locus that contributes more strongly to SA than other phenotypes and suggest a shared underlying biology between SA and known risk factors that is not mediated by psychiatric disorders.Peer reviewe

Die Struktur von zweidimensionalem glasartigen Silika

0\. Introduction 1\. The Structure of Glass 2\. Methods and Experimental Implementation 3\. Precharacterization of Thin Silica Films on Ru(0001) 4\. The Atomic Structure of a Thin Vitreous Silica Film 5\. Comparison of Crystalline and Vitreous Phases 6\. Crystalline–Vitreous Interface in Two- Dimensional Silica 7\. Conclusion and OutlookGlasses are ubiquitous in nature and technology. They are generally classified by a lack of periodicity and order. Therefore, it is a great challenge to investigate the atomic arrangement in a glass. Silica is the prototype glass network former. The corner-sharing interconnection of the tetrahedral building units provides high flexibility in its atomic configuration. Silica glass, also known as vitreous silica, has been studied by various techniques for more than 80 years. However, most methods fail to give a direct view on the atomic arrangement in glass. Scanning probe methods possess the potential to resolve atomic surface structures in real space. To study glasses by these methods, a new class of two-dimensional glassy structures had to be designed. In this work, we address a metal-supported silica bilayer at the atomic level. A combination of low energy electron diffraction, Auger electron spectroscopy, low temperature scanning tunneling microscopy and noncontact atomic force microscopy was applied in ultrahigh vacuum. The growth mode of the thin silica films was characterized. Local measurements revealed crystalline and vitreous regions in the silica bilayer film. We analyzed high resolution images of the vitreous bilayer at different ranges of order yielding a better understanding of vitreous structures in general. In addition, the atomic arrangement in crystalline and vitreous bilayer areas was resolved and thoroughly compared to each other. Ultimately, we unraveled the crystalline--vitreous interface in the two-dimensional silica film. The presented results show that the vitreous silica bilayer qualifies for a versatile glass model system.Gläser sind allgegenwärtig in Natur und Technik. Sie werden im Allgemeinen durch fehlende Periodizität und Ordnung beschrieben. Deswegen ist es eine große Herausforderung, die atomare Struktur von Glas zu untersuchen. Silika ist das Musterbeispiel eines Glasnetzwerkbildners. Die eckenverknüpfte Verbindung der tetraedrischen Baueinheiten sorgt für eine hohe Flexibilität der atomaren Konfiguration. Seit über 80 Jahren wurde Silikaglas mittels verschiedener Techniken untersucht. Die meisten Methoden sind nicht im Stande einen direkten Einblick in die atomare Anordnung in Gläsern zu gewähren. Rastersondenmethoden besitzen das Potential, die atomare Oberflächenstruktur im Realraum aufzulösen. Um Gläser mit diesen Methoden untersuchen zu können, musste eine neue Klasse an zweidimensionalen glasartigen Strukturen entwickelt werden. Die vorliegende Arbeit behandelt eine auf einem Metallsubstrat präparierte Silikadoppellage auf der atomaren Ebene. Eine Kombination aus niederenergetischer Elektronenbeugung, Auger-Elektronenspektroskopie, Tieftemperaturrastertunnel- und -rasterkraftmikroskopie wurde im Ultrahochvakuum angewandt. Das Wachstum der dünnen Silikafilme wurde charakterisiert. Lokale Messungen zeigen, dass es kristalline und glasartige Bereiche in der Silikadoppellage gibt. Hochaufgelöste Aufnahmen der glasartigen Doppellage wurden auf unterschiedlichen Längenskalen ausgewertet und führten zu einem besseren Verständnis von amorphen Strukturen im Allgemeinen. Zusätzlich wurde die atomare Anordnung des kristallinen und glasartigen Silikafilms aufgelöst und miteinander verglichen. Schlussendlich wurde die Grenzfläche zwischen der kristallinen und glasartigen Silikadoppellage entschlüsselt. Die vorgestellten Ergebnisse zeigen, dass sich die Silikadoppellage als vielfältiges Modellsystem für Gläser eignet