64 research outputs found

    Online classification for time-domain astronomy

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    The advent of synoptic sky surveys has spurred the development of techniques for real-time classification of astronomical sources in order to ensure timely follow-up with appropriate instruments. Previous work has focused on algorithm selection or improved light curve representations, and naively convert light curves into structured feature sets without regard for the time span or phase of the light curves. In this paper, we highlight the violation of a fundamental machine learning assumption that occurs when archival light curves with long observational time spans are used to train classifiers that are applied to light curves with fewer observations. We propose two solutions to deal with the mismatch in the time spans of training and test light curves. The first is the use of classifier committees where each classifier is trained on light curves of different observational time spans. Only the committee member whose training set matches the test light curve time span is invoked for classification. The second solution uses hierarchical classifiers that are able to predict source types both individually and by sub-group, so that the user can trade-off an earlier, more robust classification with classification granularity. We test both methods using light curves from the MACHO survey, and demonstrate their usefulness in improving performance over similar methods that naively train on all available archival data.Comment: Astroinformatics workshop, IEEE International Conference on Data Mining 201

    Connessioni tra biblioteche e musei: il caso di studio della collaborazione biblioteca-museo all'Hong Kong Maritime Museum

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    Established in 2005, the Hong Kong Maritime Museum (HKMM) is a relatively new private museum that aims to collect all forms of materials related to the development of boats, ships, maritime exploration and trade, and naval warfare on the South China coast, as well as its adjacent seas.  The Museum not only serves as a unique platform for teaching and learning of the local heritage in Hong Kong, it also contributes greatly to the promotion of community engagement and social connections.  The HKMM is also equipped with its own museum library, and it is called the CSSC (China State Shipbuilding Corporation) Maritime Heritage Resource Centre.  In addition to supporting various research activities carried out by the Museum, this Resource Centre also serves as a central, and yet comprehensive repository for publications, and other archival documents on maritime heritage and history related to Southeastern China. This paper aims to compare the distinctive operational practices, and user needs between museums and libraries.  It also examines the benefits and challenges of museum-library collaborations in the new knowledge-driven society.  This paper features an interview with Kitty But (Librarian, CSSC Maritime Heritage Resource Centre, The Hong Kong Maritime Museum) and Robert Trio (Project Officer for Technology, The Hong Kong Maritime Museum), and in which they discussed their professional experiences in the fields of audience education; the implementation of different new technologies associated with the museum and library services; and various collaborative initiatives carried out between the Museum and the Resource Centre.  Upcoming challenges and opportunities faced by both the Museum and Resource Centre are also discussed in this paper.Istituito nel 2005, l'Hong Kong Maritime Museum (HKMM) è un museo privato che colleziona materiali di vario genere su imbarcazioni, esplorazioni navali e commercio, oltre ai conflitti navali sulla costa meridionale della Cina e nei mari limitrofi. Il Museo serve non solo come punto di partenza per l'insegnamento e l'apprendimento della storia di Hong Kong, ma contribuisce notevolmente alla promozione del coinvolgimento della comunità locale. L'HKMM è dotato di una propria biblioteca, CSSC (Compagnia Cantieristica Statale Cinese) Maritime Heritage Resource Centre. Oltre a dare supporto alle diverse attività di ricerca del Museo, la biblioteca serve come repository centrale di pubblicazioni e altro materiale archivistico relativo al patrimonio conservato presso l'istituzione.Scopo di questo articolo è il confronto delle pratiche operative e dei bisogni degli utenti di musei e biblioteche. Si esaminano inoltre i benefici e le problematicità emergenti dalla collaborazione tra museo e biblioteca nella società dell'informazione. Vengono riportate due interviste, rispettivamente a Kitty But, bibliotecaria presso il CSSC Maritime Heritage Resource Centre, e a Robert Trio, project officer per gli sviluppi tecnologici dell'istituzione, in cui gli intervistati discutono dell'esperienza professionale nell'ambito dell'insegnamento agli utenti, dell'implementazione di nuove tecnologie associate ai servizi di musei e biblioteche, e infine delle iniziative di collaborazione tra museo e biblioteca dell'HKMM

    RNA-Seq of Huntington's disease patient myeloid cells reveals innate transcriptional dysregulation associated with proinflammatory pathway activation

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    Innate immune activation beyond the central nervous system is emerging as a vital component of the pathogenesis of neurodegeneration. Huntington’s disease (HD) is a fatal neurodegenerative disorder caused by a CAG repeat expansion in the huntingtin gene. The systemic innate immune system is thought to act as a modifier of disease progression; however, the molecular mechanisms remain only partially understood. Here we use RNA-sequencing to perform whole transcriptome analysis of primary monocytes from thirty manifest HD patients and thirty-three control subjects, cultured with and without a proinflammatory stimulus. In contrast with previous studies that have required stimulation to elicit phenotypic abnormalities, we demonstrate significant transcriptional differences in HD monocytes in their basal, unstimulated state. This includes previously undetected increased resting expression of genes encoding numerous proinflammatory cytokines, such as IL6. Further pathway analysis revealed widespread resting enrichment of proinflammatory functional gene sets, while upstream regulator analysis coupled with Western blotting suggests that abnormal basal activation of the NFOEB pathway plays a key role in mediating these transcriptional changes. That HD myeloid cells have a proinflammatory phenotype in the absence of stimulation is consistent with a priming effect of mutant huntingtin, whereby basal dysfunction leads to an exaggerated inflammatory response once a stimulus is encountered. These data advance our understanding of mutant huntingtin pathogenesis, establish resting myeloid cells as a key source of HD immune dysfunction, and further demonstrate the importance of systemic immunity in the potential treatment of HD and the wider study of neurodegeneration

    Final Report of the Information Technology Subcommittee for the Campus Master Plan

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    Through its work, data collection, outreach, and careful review of various studies and information, the committee is led to conclude that as it moves forward with implementation of its Master Plan, UMass Boston has a tremendous opportunity to plan for and design spaces that support and promote the learning, teaching, and research requirements of the campus community. It is hoped that the recommended guidelines and standards outlined in this report will assist and inform the planning and design of new and renovated campus facilities and specifically address the technological needs of classrooms, laboratories, offices, informal study areas, and social spaces throughout the campus. As technology transforms rapidly and the needs of the campus evolve, the committee also recommends that this report is reviewed and updated on a yearly basis

    A Transcriptomic Signature of the Hypothalamic Response to Fasting and BDNF Deficiency in Prader-Willi Syndrome.

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    Transcriptional analysis of brain tissue from people with molecularly defined causes of obesity may highlight disease mechanisms and therapeutic targets. We performed RNA sequencing of hypothalamus from individuals with Prader-Willi syndrome (PWS), a genetic obesity syndrome characterized by severe hyperphagia. We found that upregulated genes overlap with the transcriptome of mouse Agrp neurons that signal hunger, while downregulated genes overlap with the expression profile of Pomc neurons activated by feeding. Downregulated genes are expressed mainly in neuronal cells and contribute to neurogenesis, neurotransmitter release, and synaptic plasticity, while upregulated, predominantly microglial genes are involved in inflammatory responses. This transcriptional signature may be mediated by reduced brain-derived neurotrophic factor expression. Additionally, we implicate disruption of alternative splicing as a potential molecular mechanism underlying neuronal dysfunction in PWS. Transcriptomic analysis of the human hypothalamus may identify neural mechanisms involved in energy homeostasis and potential therapeutic targets for weight loss

    Abundant small RNAs in the reproductive tissues and eggs of the honey bee, Apis mellifera

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    Background: Polyandrous social insects such as the honey bee are prime candidates for parental manipulation of gene expression in offspring. Although there is good evidence for parent-of-origin effects in honey bees the epigenetic mechanisms that underlie these effects remain a mystery. Small RNA molecules such as miRNAs, piRNAs and siRNAs play important roles in transgenerational epigenetic inheritance and in the regulation of gene expression during development. Results: Here we present the first characterisation of small RNAs present in honey bee reproductive tissues: ovaries, spermatheca, semen, fertilised and unfertilised eggs, and testes. We show that semen contains fewer piRNAs relative to eggs and ovaries, and that piRNAs and miRNAs which map antisense to genes involved in DNA regulation and developmental processes are differentially expressed between tissues. tRNA fragments are highly abundant in semen and have a similar profile to those seen in the semen of other animals. Intriguingly we also find abundant piRNAs that target the sex determination locus, suggesting that piRNAs may play a role in honey bee sex determination. Conclusions: We conclude that small RNAs may play a fundamental role in honey bee gametogenesis and reproduction and provide a plausible mechanism for parent-of-origin effects on gene expression and reproductive physiology

    Susceptibility to tuberculosis is associated with variants in the ASAP1 gene encoding a regulator of dendritic cell migration

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    Human genetic factors predispose to tuberculosis (TB). We studied 7.6 million genetic variants in 5,530 people with pulmonary TB and in 5,607 healthy controls. In the combined analysis of these subjects and the follow-up cohort (15,087 TB patients and controls altogether), we found an association between TB and variants located in introns of the ASAP1 gene on chromosome 8q24 (P = 2.6 × 10−11 for rs4733781; P = 1.0 × 10−10 for rs10956514). Dendritic cells (DCs) showed high ASAP1 expression that was reduced after Mycobacterium tuberculosis infection, and rs10956514 was associated with the level of reduction of ASAP1 expression. The ASAP1 protein is involved in actin and membrane remodeling and has been associated with podosomes. The ASAP1-depleted DCs showed impaired matrix degradation and migration. Therefore, genetically determined excessive reduction of ASAP1 expression in M. tuberculosis–infected DCs may lead to their impaired migration, suggesting a potential mechanism of predisposition to TB
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