17,713 research outputs found

    Decoding billions of integers per second through vectorization

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    In many important applications -- such as search engines and relational database systems -- data is stored in the form of arrays of integers. Encoding and, most importantly, decoding of these arrays consumes considerable CPU time. Therefore, substantial effort has been made to reduce costs associated with compression and decompression. In particular, researchers have exploited the superscalar nature of modern processors and SIMD instructions. Nevertheless, we introduce a novel vectorized scheme called SIMD-BP128 that improves over previously proposed vectorized approaches. It is nearly twice as fast as the previously fastest schemes on desktop processors (varint-G8IU and PFOR). At the same time, SIMD-BP128 saves up to 2 bits per integer. For even better compression, we propose another new vectorized scheme (SIMD-FastPFOR) that has a compression ratio within 10% of a state-of-the-art scheme (Simple-8b) while being two times faster during decoding.Comment: For software, see https://github.com/lemire/FastPFor, For data, see http://boytsov.info/datasets/clueweb09gap

    Work Based Learning, Enterprise Education and small family business

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    The world of education and work are adapting to the ever-changing political, economic and policy landscape as evidenced by approaches to enterprise education and work based learning. Work based learning often focuses on the development of employability skills of learners (e.g. Costley and Armsby, 2007) whereas the focus of enterprise education is often placed on developing skills, attributes and behaviours to encourage entrepreneurship and to help people cope with the uncertainties associated with the flexible market ‘gig’ economy (e.g. Gibb, 1993). This paper compares and contrasts these two educational concepts and in so doing looks at where they overlap and what one might learn from the other (Jones and Iredale, 2014). The paper draws on the literature to build theory and assesses the blending of the two concepts via case study analysis founded upon two Erasmus+ programme projects that tackle succession planning in small family businesses. This paper addresses issues around succession planning in small family businesses and the design of a higher education curriculum that brings together Work Based Learning (WBL) and Enterprise Education. The blending of the two concepts is justified in that WBL is embedded in the structures, processes, practices and cultures of small family businesses. In such environments learning is largely informal, is passed on and acquired as part of everyday activity. At the point of succession there is a need to adopt an Enterprise Education approach to help re-think the original entrepreneurial skills, attributes and behaviours of the business founder for a new generation, changing environment and set of business circumstances

    Barbarians at the gate

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    Optimal client recommendation for market makers in illiquid financial products

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    The process of liquidity provision in financial markets can result in prolonged exposure to illiquid instruments for market makers. In this case, where a proprietary position is not desired, pro-actively targeting the right client who is likely to be interested can be an effective means to offset this position, rather than relying on commensurate interest arising through natural demand. In this paper, we consider the inference of a client profile for the purpose of corporate bond recommendation, based on typical recorded information available to the market maker. Given a historical record of corporate bond transactions and bond meta-data, we use a topic-modelling analogy to develop a probabilistic technique for compiling a curated list of client recommendations for a particular bond that needs to be traded, ranked by probability of interest. We show that a model based on Latent Dirichlet Allocation offers promising performance to deliver relevant recommendations for sales traders.Comment: 12 pages, 3 figures, 1 tabl

    Penicillin-resistant isolates of Neisseria-lactamica produce altered forms of penicillin-binding protein-2 that arose by interspecies horizontal gene-transfer

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    Isolates of Neisseria lactamica that have increased resistance to penicillin have emerged in recent years. Resistance to penicillin was shown to be due to the production of altered forms of penicillin-binding protein 2 (PBP 2) that have reduced affinity for the antibiotic. The sequences of the PBP 2 genes (penA) from two penicillin-resistant isolates were almost identical (less than or equal to 1% sequence divergence) to that of a penicillin-susceptible isolate, except in a 175-bp region where the resistant and susceptible isolates differed by 27%. The nucleotide sequences of these divergent regions were identical (or almost identical) to the sequence of the corresponding region of the penA gene of N. flavescens NCTC 8263. Altered forms of PBP 2 with decreased affinity for penicillin in the two penicillin-resistant isolates of N. lactamica appear, therefore, to have arisen by the replacement of part of the N. lactamica penA gene with the corresponding region from the penA gene of N. flavescens

    Boundaries of Semantic Distraction: Dominance and Lexicality Act at Retrieval

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    Three experiments investigated memory for semantic information with the goal of determining boundary conditions for the manifestation of semantic auditory distraction. Irrelevant speech disrupted the free recall of semantic category-exemplars to an equal degree regardless of whether the speech coincided with presentation or test phases of the task (Experiment 1) and occurred regardless of whether it comprised random words or coherent sentences (Experiment 2). The effects of background speech were greater when the irrelevant speech was semantically related to the to-be-remembered material, but only when the irrelevant words were high in output dominance (Experiment 3). The implications of these findings in relation to the processing of task material and the processing of background speech is discussed

    In Vitro Functional Analyses of Infrequent Nucleotide Variants in the Lactase Enhancer Reveal Different Molecular Routes to Increased Lactase Promoter Activity and Lactase Persistence

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    The genetic trait that allows intestinal lactase to persist into adulthood in some 35% of humans worldwide operates at the level of transcription, the effect being caused by cis-acting nucleotide changes upstream of the lactase gene (LCT). A single nucleotide substitution, -13910 C>T, the first causal variant to be identified, accounts for lactase persistence over most of Europe. Located in a region shown to have enhancer function in vitro, it causes increased activity of the LCT promoter in Caco-2 cells, and altered transcription factor binding. Three other variants in close proximity, -13907 C>G, -13915 T>C and -14010 G>C, were later shown to behave in a similar manner. Here, we study four further candidate functional variants. Two, -14009 T>G and -14011 C>T, adjacent to the well-studied -14010 G>C variant, also have a clear effect on promoter activity upregulation as assessed by transfection assays, but notably are involved in different molecular interactions. The results for the two other variants (-14028 T>C, -13779 G>C) were suggestive of function, -14028*C showing a clear change in transcription factor binding, but no obvious effect in transfections, while -13779*G showed greater effect in transfections but less on transcription factor binding. Each of the four variants arose on independent haplotypic backgrounds with different geographic distribution

    From Wonder to Curiosity in Early Modern Travel Writing.

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    The early modern period saw an unprecedented rise in travel and travel writing. As voyages brought travellers to new and scarcely recorded parts of the world, this in turn led to encounters with what we might term the ‘wondrous,’ phenomena apparently defying all explanation and evoking a wonder reaction in those witnessing it. At the same time there existed ‘curiosities,’ interesting or intriguing objects sometimes displayed in large collections, or kept for personal pleasure. Wonders and curiosities, especially in regards to travel, were interlinked. This thesis examines how the process was one of transition, with the wondrous often being lowered to the level of the merely curious. The discussion encompasses in part an analysis of the terms ‘wonder’ and ‘curiosity,’ and argues that a separation of the two is essential in understanding how knowledge was constructed during the period. A careful analysis of how wonder was, and still is, transformed into curiosity, illuminates how new information is incorporated into existing knowledge structures. The thesis traces this development with reference to a wide range of source material including medicinal texts, legal records and dramatic works, but travel remains the crux of the discussion. I argue that the nature of travel writing and the associated methodologies of collection and classification, were a catalyst for the transformation of the wondrous into the merely curious

    YouTube as a source of information for patients considering surgery for ulcerative colitis

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    © 2017 Elsevier Inc. Background With the range of health information online, assessing the resources that patients access may improve the content of preoperative information. Our aim was to assess the content of the most viewed videos on YouTube related to surgery for ulcerative colitis (UC). Methods YouTube was searched for videos containing information on surgery for UC. The 50 most viewed videos were identified and user interaction analyzed. Upload source was classified as patient, individual health care professional (HCP), or hospital/professional association. Video content was categorized using an inductive thematic analysis on a purposive sample list of videos. The overarching theme of each video was classified once data saturation was achieved. Results Thirty videos were uploaded by patients, 15 by hospitals and 5 by HCPs. Seventeen videos (34%) discussed life after surgery. Sixteen of these were uploaded by patients who had previously undergone surgery for UC. No videos of this theme were uploaded by HCPs. Ten videos (20%) described a number of different operations. Other themes identified were alternative health therapies (12%), colonoscopy (12%), life with UC (8%), miscellaneous (8%), and education for HCPs (6%). Patient uploaded videos had significantly more comments (P = 0.0079), with 28% of comments on patient videos being users requesting further information. Conclusions Understanding the sequelae of surgery is most important to preoperative patients. There are a lack of professional videos addressing this topic on YouTube. HCPs must participate in the production of videos and adapt preoperative consultations to address common preoperative concerns
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