79 research outputs found

    Physics and Applications of Laser Diode Chaos

    Full text link
    An overview of chaos in laser diodes is provided which surveys experimental achievements in the area and explains the theory behind the phenomenon. The fundamental physics underpinning this behaviour and also the opportunities for harnessing laser diode chaos for potential applications are discussed. The availability and ease of operation of laser diodes, in a wide range of configurations, make them a convenient test-bed for exploring basic aspects of nonlinear and chaotic dynamics. It also makes them attractive for practical tasks, such as chaos-based secure communications and random number generation. Avenues for future research and development of chaotic laser diodes are also identified.Comment: Published in Nature Photonic

    Corpus annotation for mining biomedical events from literature

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Advanced Text Mining (TM) such as semantic enrichment of papers, event or relation extraction, and intelligent Question Answering have increasingly attracted attention in the bio-medical domain. For such attempts to succeed, text annotation from the biological point of view is indispensable. However, due to the complexity of the task, semantic annotation has never been tried on a large scale, apart from relatively simple term annotation.</p> <p>Results</p> <p>We have completed a new type of semantic annotation, event annotation, which is an addition to the existing annotations in the GENIA corpus. The corpus has already been annotated with POS (Parts of Speech), syntactic trees, terms, etc. The new annotation was made on half of the GENIA corpus, consisting of 1,000 Medline abstracts. It contains 9,372 sentences in which 36,114 events are identified. The major challenges during event annotation were (1) to design a scheme of annotation which meets specific requirements of text annotation, (2) to achieve biology-oriented annotation which reflect biologists' interpretation of text, and (3) to ensure the homogeneity of annotation quality across annotators. To meet these challenges, we introduced new concepts such as Single-facet Annotation and Semantic Typing, which have collectively contributed to successful completion of a large scale annotation.</p> <p>Conclusion</p> <p>The resulting event-annotated corpus is the largest and one of the best in quality among similar annotation efforts. We expect it to become a valuable resource for NLP (Natural Language Processing)-based TM in the bio-medical domain.</p

    The IceCube Neutrino Observatory - Contributions to ICRC 2017 Part VI: IceCube-Gen2, the Next Generation Neutrino Observatory

    Get PDF
    Papers on research & development towards IceCube-Gen2, the next generation neutrino observatory at South Pole, submitted to the 35th International Cosmic Ray Conference (ICRC 2017, Busan, South Korea) by the IceCube-Gen2 Collaboration

    Multi-messenger observations of a binary neutron star merger

    Get PDF
    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

    Crowdsourcing in business and management disciplines: an integrative literature review

    Get PDF
    The objective of this study is to review crowdsourcing literature of the business and management disciplines and to know its relation with the open innovation concept. A systematic literature review is used in this study. Studies on crowdsourcing are published mostly in recent years, 2011-2013. Studies are highly dispersed, published in a very wide range of journals and are mostly based on a single case as data source. Content analysis of the findings of articles are performed to synthesize the findings in the extant literature. Most of the qualitative articles used single case method and most of the quantitative studies relied on online survey over a single crowdsourcing platform. Studies and scholars in the literature are from a limited number of countries. Although crowdsourcing as a concept overlaps with the open innovation concept, by no means, it can be considered a concept under the broad umbrella of open innovation concept. Based on identified gaps, future research avenues are presented

    Second primary malignancies induced by radioactive iodine treatment of differentiated thyroid carcinoma - a critical review and evaluation of the existing evidence.

    Get PDF
    PURPOSE: Concern is growing about long-term side effects of differentiated thyroid cancer treatment, most notably radioactive iodine (RAI) therapy. However, published studies on the subject have had heterogeneous cohorts and conflicting results. This review seeks to provide an updated evaluation of published evidence, and to elucidate the risk of second primary malignancies (SPMs), especially secondary hematologic malignancies (SHMs), attributable to RAI therapy. METHODS: An extensive literature search was performed in Ovid MEDLINE, Ovid MEDLINE and In-Process & Other Non-Indexed Citations, Ovid MEDLINE Epub Ahead of Print, Cochrane Central Register of Controlled Trials (CENTRAL) and PubMed. Studies regarding RAI-induced SPMs or a dose-response relationship between RAI therapy and SPMs were identified, 10 of which were eligible for the analysis. We evaluated risk of bias in each study and judged quality of evidence (QOE) across all studies using the Grading of Recommendations, Assessment, Development and Evaluations approach. RESULTS: For the outcome "SPM", the relative effect (relative risk, hazard ratio, or odds ratio) of RAI vs. no RAI ranged from 1.14 to 1.84 across studies, but most results were not statistically significant. For the outcome "SHM", reported relative effects ranged from 1.30 to 2.50, with 2/3 of the studies presenting statistically significant results. In 7/8 of the studies, increased risk for SPM was shown with increasing cumulative RAI activity. QOE was "very low" regarding SPM after RAI and regarding a dose-response relationship, and "low" for SHM after RAI. CONCLUSION: Based on low quality evidence, an excess risk for the development of SPM cannot be excluded but is expected to be small
    corecore