4,856 research outputs found

    Equivariant Transduction through Invariant Alignment

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    The ability to generalize compositionally is key to understanding the potentially infinite number of sentences that can be constructed in a human language from only a finite number of words. Investigating whether NLP models possess this ability has been a topic of interest: SCAN (Lake and Baroni, 2018) is one task specifically proposed to test for this property. Previous work has achieved impressive empirical results using a group-equivariant neural network that naturally encodes a useful inductive bias for SCAN (Gordon et al., 2020). Inspired by this, we introduce a novel group-equivariant architecture that incorporates a group-invariant hard alignment mechanism. We find that our network's structure allows it to develop stronger equivariance properties than existing group-equivariant approaches. We additionally find that it outperforms previous group-equivariant networks empirically on the SCAN task. Our results suggest that integrating group-equivariance into a variety of neural architectures is a potentially fruitful avenue of research, and demonstrate the value of careful analysis of the theoretical properties of such architectures.Comment: Accepted at COLING 202

    Inner wellbeing: concept and validation of a new approach to subjective perceptions of wellbeing-India

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    © The Author(s) 2013. This article is published with open access at Springerlink.com. This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.This paper describes the conceptual development of a multi-domain, psychosocial model of 'Inner Wellbeing' (IWB) and assesses the construct validity of the scale designed to measure it. IWB expresses what people think and feel they are able to be and do. Drawing together scholarship in wellbeing and international development it is grounded in field research in marginalised, rural communities in the global South. Results from research in India at two points in time (2011 and 2013) are reported. At Time 1 (n = 287), we were unable to confirm an eight-factor, correlated model as distinct yet interrelated domains. However, at Time 2 (n = 335), we were able to confirm a revised, seven-factor correlated model with economic confidence, agency and participation, social connections, close relationships, physical and mental health, competence and self-worth, and values and meaning (five items per domain) as distinct yet interrelated domains. In particular, at Time 2, a seven-factor, correlated model provided a significantly better fit to the data than did a one-factor model.This work is supported by the Economic and Social Research Council/Department for International Development Joint Scheme for Research on International Development (Poverty Alleviation) grant number RES-167-25-0507 ES/H033769/1. Special thanks are due to Chaupal and Gangaram Paikra, Pritam Das, Usha Kujur, Kanti Minjh, Susanna Siddiqui, and Dinesh Tirkey

    The HI Content of Local Late-Type Galaxies

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    We present a solid relationship between the neutral hydrogen (HI) disk mass and the stellar disk mass of late-type galaxies in the local universe. This relationship is derived by comparing the stellar disk mass function from the Sloan Digital Sky Survey and the HI mass function from the HI Parkes All Sky Survey (HIPASS). We find that the HI mass in late-type galaxies tightly correlates with the stellar mass over three orders of magnitude in stellar disk mass. We cross-check our result with that obtained from a sample of HIPASS objects for which the stellar mass has been obtained by inner kinematics. In addition, we derive the HI versus halo mass relationship and the dependence of all the baryonic components in spirals on the host halo mass. These relationships bear the imprint of the processes ruling galaxy formation, and highlight the inefficiency of galaxies both in forming stars and in retaining their pristine HI gas.Comment: 6 pages, 5 figures. Match to the published version. References update

    Transcription factor interactions explain the context-dependent activity of CRX binding sites

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    The effects of transcription factor binding sites (TFBSs) on the activity of a cis-regulatory element (CRE) depend on the local sequence context. In rod photoreceptors, binding sites for the transcription factor (TF) Cone-rod homeobox (CRX) occur in both enhancers and silencers, but the sequence context that determines whether CRX binding sites contribute to activation or repression of transcription is not understood. To investigate the context-dependent activity of CRX sites, we fit neural network-based models to the activities of synthetic CREs composed of photoreceptor TFBSs. The models revealed that CRX binding sites consistently make positive, independent contributions to CRE activity, while negative homotypic interactions between sites cause CREs composed of multiple CRX sites to function as silencers. The effects of negative homotypic interactions can be overcome by the presence of other TFBSs that either interact cooperatively with CRX sites or make independent positive contributions to activity. The context-dependent activity of CRX sites is thus determined by the balance between positive heterotypic interactions, independent contributions of TFBSs, and negative homotypic interactions. Our findings explain observed patterns of activity among genomic CRX-bound enhancers and silencers, and suggest that enhancers may require diverse TFBSs to overcome negative homotypic interactions between TFBSs

    Genomics reveals historic and contemporary transmission dynamics of a bacterial disease among wildlife and livestock

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    Whole-genome sequencing has provided fundamental insights into infectious disease epidemiology, but has rarely been used for examining transmission dynamics of a bacterial pathogen in wildlife. In the Greater Yellowstone Ecosystem (GYE), outbreaks of brucellosis have increased in cattle along with rising seroprevalence in elk. Here we use a genomic approach to examine Brucella abortus evolution, cross-species transmission and spatial spread in the GYE. We find that brucellosis was introduced into wildlife in this region at least five times. The diffusion rate varies among Brucella lineages (∼3 to 8 km per year) and over time. We also estimate 12 host transitions from bison to elk, and 5 from elk to bison. Our results support the notion that free-ranging elk are currently a self-sustaining brucellosis reservoir and the source of livestock infections, and that control measures in bison are unlikely to affect the dynamics of unrelated strains circulating in nearby elk populations

    The Fermionic Quantum Emulator

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    The fermionic quantum emulator (FQE) is a collection of protocols for emulating quantum dynamics of fermions efficiently taking advantage of common symmetries present in chemical, materials, and condensed-matter systems. The library is fully integrated with the OpenFermion software package and serves as the simulation backend. The FQE reduces memory footprint by exploiting number and spin symmetry along with custom evolution routines for sparse and dense Hamiltonians, allowing us to study significantly larger quantum circuits at modest computational cost when compared against qubit state vector simulators. This release paper outlines the technical details of the simulation methods and key technical advantages

    Retention of Physician Assistants within a Specialty after Completion of a Postgraduate Training Program

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    Background: The advantages of a specialized training program have led to over 84 postgraduate training programs for Physician Assistants (PAs) covering over 25 specialties. Employee lateral mobility is more prevalent within the PA profession, which allows PA providers to switch between medical specialties. The versatility of PAs promotes higher turnover rates compared to physician counterparts. These high turnover rates can result in increased institutional burden. Postgraduate PA programs provide pre-employment exposure to more in-depth medical training, enabling a well-rounded knowledge base of the PA’s roles and responsibilities, minimizing turnover rates. Purpose: The goal of this survey study is to identify PA graduates’ perceptions of their retention rate, job satisfaction within a given specialty, factors influencing a PA’s decision to change their specialty, and specialty preparation provided by postgraduate training programs and specific educational training. Methods: A mixed method design was utilized to survey both program directors and graduates of PA postgraduate training programs. Results: Of the 398 postgraduate program graduates, 196 (49%) accepted a job within the institution where they trained. Across all postgraduate training programs, 87% of graduates have not changed their specialty since program completion. Ninety-six percent of respondents felt their postgraduate training gave them an accurate preview of employment in their specialty of interest, and all postgraduates would recommend a postgraduate training program to a new PA graduate

    Gender inequality in science, technology, engineering and mathematics: gendered time disparities in perceived and actual time spent in practical laboratory-based activities

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    This is the final version. Available on open access from Frontiers Media via the DOI in this recordData availability statement: The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.Lab-based activities provide essential skills for students within STEM disciplines, as lab activities provide students with research skills and science knowledge. Therefore, it is critical to note that female students have reported feeling less confident in conducting lab-based activities and report a lower sense of belonging in the lab. In two studies (N = 544) we examined gender differences in the time that students spent, and perceived they spent, on various laboratory-based activities. We predicted that female (vs. male) students in science, technology, engineering and mathematics (STEM) would both perceive, and actually spend, less time in practical, science-specific activities, such as using equipment, compared to observing or note-taking. Study 1a (N = 227) was an online, cross-sectional survey where university STEM students reported their perceptions of time spent during lab-based practical activities, and how satisfied they were with their time spent in these activities. Study 1b (N = 318) was an observational study of university practical lab sessions in STEM disciplines. Our findings demonstrated that female (vs. male) students (1) spent more time recording and taking notes during lab sessions, (2) did not perceive, yet actually spent, less time in the lab using equipment, and (3) were equally satisfied with their time in the lab using equipment. Together, these results suggest that women occupy stereotypically gendered roles in the STEM lab, spending less time on activities that are key for their professional development. Furthermore, the fact that students from disciplines with more female participation were more satisfied with their time spent in lab activities can promote the insidious effects of assessing gender participation and equality in STEM through numbers only. The differences in time spent in lab activities-yet the lack of acknowledge of these differences-opens the discussion about how women might be receiving reduced utility from their programmes, and that universities may not be delivering on their obligations to ensure equal access to teaching resource and opportunities

    Assessing simulation ecosystem processes for climate variability research at Glacier National Park

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    Glacier National Park served as a test site for ecosystem analyses that involved a suite of integrated models embedded within a geographic information system. The goal of the exercise was to provide managers with maps that could illustrate probable shifts in vegetation, net primary production (NPP), and hydrologic responses associated with two selected climatic scenarios. The climatic scenarios were (a) a recent 12-yr record of weather data, and (b) a reconstituted set that sequentially introduced in repeated 3-yr intervals wetter–cooler, drier–warmer, and typical conditions. To extrapolate the implications of changes in ecosystem processes and resulting growth and distribution of vegetation and snowpack, the model incorporated geographic data. With underlying digital elevation maps, soil depth and texture, extrapolated climate, and current information on vegetation types and satellite-derived estimates of leaf area indices, simulations were extended to envision how the park might look after 120 yr. The predictions of change included underlying processes affecting the availability of water and nitrogen. Considerable field data were acquired to compare with model predictions under current climatic conditions. In general, the integrated landscape models of ecosystem processes had good agreement with measured NPP, snowpack, and streamflow, but the exercise revealed the difficulty and necessity of averaging point measurements across landscapes to achieve comparable results with modeled values. Under the extremely variable climate scenario significant changes in vegetation composition and growth as well as hydrologic responses were predicted across the park. In particular, a general rise in both the upper and lower limits of treeline was predicted. These shifts would probably occur along with a variety of disturbances (fire, insect, and disease outbreaks) as predictions of physiological stress (water, nutrients, light) altered competitive relations and hydrologic responses. The use of integrated landscape models applied in this exercise should provide managers with insights into the underlying processes important in maintaining community structure, and at the same time, locate where changes on the landscape are most likely to occur

    Core pathway mutations induce de-differentiation of murine astrocytes into glioblastoma stem cells that are sensitive to radiation but resistant to temozolomide

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    Glioma stem cells (GSCs) from human glioblastomas (GBMs) are resistant to radiation and chemotherapy and may drive recurrence. Treatment efficacy may depend on GSCs, expression of DNA repair enzymes such as methylguanine methyltransferase (MGMT), or transcriptome subtype
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