Leveraging Relational Structure through Message Passing for Modelling Non-Euclidean Data

Modelling non-Euclidean data is difficult since objects for comparison can be formed of different numbers of constituent parts with different numbers of relations between them, and traditional (Euclidean) methods are non-trivial to apply. Message passing enables such modelling by leveraging the structure of the relations within a (or between) given object(s) in order to represent and compare structure in a vectorized form of fixed dimensions. In this work, we contribute novel message passing techniques that improve state of the art for non-Euclidean modelling in a set of specifically chosen domains. In particular, (1) we introduce an attention-based structure-aware global pooling operator for graph classification and demonstrate its effectiveness on a range of chemical property prediction benchmarks, we also show that our method outperforms state of the art graph classifiers in a graph isomorphism test, and demonstrate the interpretability of our method with respect to the learned attention coefficients. (2) We propose a style similarity measure for Boundary Representations (B-Reps) that leverages the style signals in the second order statistics of the activations in a pre-trained (unsupervised) 3D encoder, and learns their relative importance to an end-user through few-shot learning. Our approach differs from existing data-driven 3D style methods since it may be used in completely unsupervised settings. We show quantitatively that our proposed method with B-Reps is able to capture stronger style signals than alternative methods on meshes and point clouds despite its significantly greater computational efficiency. We also show it is able to generate meaningful style gradients with respect to the input shape. (3) We introduce a novel message passing-based model of computation and demonstrate its effectiveness in expressing the complex dependencies of biological systems necessary to model life-like systems and tracing cell lineage during cancerous tumour growth, and demonstrate the improvement over existing methods in terms of post-analysis

Mental health: future challenges

The aim of the Foresight Project on Mental Capital and Wellbeing(www.foresight.gov.uk) is to advise the Government on how to achieve the best possible mental development and mental wellbeing for everyone in the UK in the future. The starting point of the Project was to generate an understanding of the science of mental capital and wellbeing (MCW) and to develop a vision for how the size and nature of the challenges exposed by the Project could evolve over the next 20 years. To make this analysis tractable, the work was divided into five broad areas: ● Mental capital through life ● Learning through life ● Mental health ● Wellbeing and work, and ● Learning difficulties. This report presents the findings for “Mental health” and draws upon a comprehensive assessment of the scientific state-of-the art: overall, around 80 reviews have been commissioned across the five areas. Mental health is a term which is used in a number of different ways and which has unfortunately acquired a substantial stigma in all layers of society. While the main focus of this report is on mental ill-health, positive mental health is also vitally important and is also discussed. However, a more comprehensive consideration of positive mental health has been performed in other parts of the Project (as commissioned reviews and in the context of the future of work. This report starts by looking at the situation today, examining the prevalence of important categories of mental disorder. It then considers the risk and protective factors which influence mental ill health, and determines how its prevalence and impact could change in the future, if existing policies and expenditure remain broadly unchanged. An assessment of strategic choices and interventions to meet the future challenges of mental health (and the challenges associated with the other four areas listed above) will be documented in the final Project report which is due for publication in the autumn of 2008

Upper gastrointestinal hemorrhage: Have new therapeutics made a difference?

BACKGROUND: To explore the distribution of etiologies and risk factors of upper gastrointestinal hemorrhage (UGH) in the context of new pharmacologic therapies that may alter the risk of UGH. METHODS: Retrospective study performed on eligible UGH inpatients at 2 academic medical centers, between July 1, 2001 and June 30, 2003. Administrative data and chart review were used to identify demographics, UGH risk factors, and UGH etiologies. Bivariate and multivariate analyses were performed to describe distributions and associations of risk factors and etiologies. RESULTS: UGH was identified in 227 subjects, with ED (n = 99; 44%), peptic ulcer disease (PUD) (n = 75; 33%), and variceal bleeds (n = 39; 17%) accounting for the majority of bleeds. Known risk factors for UGH occurred in 70% (n = 156) of subjects (prior UGH 43% [n = 90], nonsteroidal anti-inflammatory drug (NSAID) use 23% [n = 52], aspirin [ASA] use 25% [n = 57], NSAID + ASA use 6.6% [n = 15]), while 19% (n = 42) were using a proton-pump inhibitor (PPI) and 5% (n = 11) a cyclooxygenase-2 (COX-2) inhibitor. Subjects at site 1 were more likely to have ED (odds ratio [OR], 7.1; P < 0.001) and less likely to have variceal bleeding (OR, 0.12; P = 0.009) in multivariate analyses. Preventive therapy did not differ between sites. CONCLUSIONS: Unlike older studies, PUD was not the most common etiology, suggesting that advances in Helicobacter pylori (H. pylori) eradication may affect the epidemiology of UGH. Despite advances in therapeutics of acid-related disease, ED accounted for the majority of UGH. Most subjects had risk factors for UGH and most were not receiving protective therapy. Large between site-differences in the distribution of etiologies existed

Do Hospitalists or Physicians with Greater Inpatient HIV Experience Improve HIV Care in the Era of Highly Active Antiretroviral Therapy? Results from a Multicenter Trial of Academic Hospitalists

Background. Little is known about the effect of provider type and experience on outcomes, resource use, and processes of care of hospitalized patients with human immunodeficiency virus (HIV) infection. Hospitalists are caring for this population with increasing frequency. Methods. Data from a natural experiment in which patients were assigned to physicians on the basis of call cycle was used to study the effects of provider type—that is, hospitalist versus non hospitalist—and HIV-specific inpatient experience on resource use, outcomes, and selected measures of processes of care at 6 academic institutions. Administrative data, inpatient interviews, 30-day follow-up interviews, and the National Death Index were used to measure outcomes. Results. A total of 1207 patients were included in the analysis. There were few differences in resource use, outcomes, and processes of care by provider type and experience with HIV-infected inpatients. Patients who received hospitalist care demonstrated a trend toward increased length of hospital stay compared with patients who did not receive hospitalist care (6.0 days vs. 5.2 days; Pp .13). Inpatient providers with moderate experience with HIV-infected patients were more likely to coordinate care with outpatient providers (odds ratio, 2.40; Pp .05) than were those with the least experience with HIV-infected patients, but this pattern did not extend to providers with the highest level of experience. Conclusion. Provider type and attending physician experience with HIV-infected inpatients had minimal effect on the quality of care of HIV-infected inpatients. Approaches other than provider experience, such as the use of multidisciplinary inpatient teams, may be better targets for future studies of the outcomes, processes of care, and resource use of HIV-infected inpatients

Molecular Characterization of Putative Chordoma Cell Lines

Immortal tumor cell lines are an important model system for cancer research, however, misidentification and cross-contamination of cell lines are a common problem. Seven chordoma cell lines are reported in the literature, but none has been characterized in detail. We analyzed gene expression patterns and genomic copy number variations in five putative chordoma cell lines (U-CH1, CCL3, CCL4, GB60, and CM319). We also created a new chordoma cell line, U-CH2, and provided genotypes for cell lines for identity confirmation. Our analyses revealed that CCL3, CCL4, and GB60 are not chordoma cell lines, and that CM319 is a cancer cell line possibly derived from chordoma, but lacking expression of key chordoma biomarkers. U-CH1 and U-CH2 both have gene expression profiles, copy number aberrations, and morphology consistent with chordoma tumors. These cell lines also harbor genetic changes, such as loss of p16, MTAP, or PTEN, that make them potentially useful models for studying mechanisms of chordoma pathogenesis and for evaluating targeted therapies

Reproductive Aging, Sex Steroids, and Mood Disorders

Epidemiologic studies have documented that the majority of women do not become depressed during the menopause transition. However, recent longitudinal studies suggest that in some women, the events related to the menopause transition could play a role in the onset of depression. In this article we review evidence suggesting a relationship between the menopause transition and depression. Additionally, we describe several findings that suggest a role of ovarian hormones in the onset of these depressions, including the clustering of episodes of depression during the stage of the menopause transition that is accompanied by estradiol withdrawal, and the therapeutic effects of short-term estradiol in depressed perimenopausal women. Finally, we discuss possible causes of affective disturbances during the menopause transition