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    L\'evy walks

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    Random walk is a fundamental concept with applications ranging from quantum physics to econometrics. Remarkably, one specific model of random walks appears to be ubiquitous across many fields as a tool to analyze transport phenomena in which the dispersal process is faster than dictated by Brownian diffusion. The L\'{e}vy walk model combines two key features, the ability to generate anomalously fast diffusion and a finite velocity of a random walker. Recent results in optics, Hamiltonian chaos, cold atom dynamics, bio-physics, and behavioral science demonstrate that this particular type of random walks provides significant insight into complex transport phenomena. This review provides a self-consistent introduction to L\'{e}vy walks, surveys their existing applications, including latest advances, and outlines further perspectives.Comment: 50 page

    TOWARDS INSTITUTIONAL INFRASTRUCTURES FOR E-SCIENCE: The Scope of the Challenge

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    The three-fold purpose of this Report to the Joint Information Systems Committee (JISC) of the Research Councils (UK) is to: • articulate the nature and significance of the non-technological issues that will bear on the practical effectiveness of the hardware and software infrastructures that are being created to enable collaborations in e- Science; • characterise succinctly the fundamental sources of the organisational and institutional challenges that need to be addressed in regard to defining terms, rights and responsibilities of the collaborating parties, and to illustrate these by reference to the limited experience gained to date in regard to intellectual property, liability, privacy, and security and competition policy issues affecting scientific research organisations; and • propose approaches for arriving at institutional mechanisms whose establishment would generate workable, specific arrangements facilitating collaboration in e-Science; and, that also might serve to meet similar needs in other spheres such as e- Learning, e-Government, e-Commerce, e-Healthcare. In carrying out these tasks, the report examines developments in enhanced computer-mediated telecommunication networks and digital information technologies, and recent advances in technologies of collaboration. It considers the economic and legal aspects of scientific collaboration, with attention to interactions between formal contracting and 'private ordering' arrangements that rest upon research community norms. It offers definitions of e-Science, virtual laboratories, collaboratories, and develops a taxonomy of collaborative e-Science activities which is implemented to classify British e-Science pilot projects and contrast these with US collaboratory projects funded during the 1990s. The approach to facilitating inter-organizational participation in collaborative projects rests upon the development of a modular structure of contractual clauses that permit flexibility and experience-based learning.

    Recent advances in pharmaceutical sciences VII

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    The E-book series Recent Advances in Pharmaceutical Sciences reports research contributions from different areas of the multidisciplinary field of Pharmaceutical Sciences. This seventh volume consists of nine chapters, mainly dealing with the fields of botany, physiology, food science, biochemistry & molecular biology, plant physiology, microbiology, parasitology, pharmacology, and medicinal chemistry

    Machine Learning + Marine Science: Critical Role of Partnerships in Norway

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    In this essay, we review some recent advances in developing machine learning (ML) methods for marine science applications in Norway. We focus mostly on deep learning (DL) methods and review the challenges we have faced in the process, including data preparation, (lack of) labelled training data, and interpretability. We also present the partnerships that have been formed between e-science institutions and marine science institutions in Norway. These partnerships have been instrumental in moving this effort forward and have been fuelled by grants from the Norwegian Research Council. The last addition to this collaboration is the recent centres for research-based innovation in Marine Acoustic Abundance Estimation and Backscatter Classification (CRIMAC) and Visual Intelligence (VI).publishedVersio

    The great divide in scientific productivity. Why the average scientist does not exist.

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    We use a quantile regression approach to estimate the e¤ects of age, gender, research funding, teaching load and other observed characteristics of academic researchers on the full distribution of research performance, both in its quantity (publications) and quality (citations) dimension. Exploiting the panel nature of our dataset, we estimate a correlated random-e¤ects quantile regression model, accounting for unobserved heterogeneity of researchers. We employ recent advances in quantile regression that allow its application to count data. Estimation of the model for a panel of biomedical and exact scientists at the KU Leuven in the period 1992-2001 shows strong support for our quantile regression approach, revealing the di¤erential impact of almost all regressors along the distribution. We also …nd that variables like funding, teaching load and cohort have a di¤erent impact on research quantity than on research quality.economics of science; research productivity; quantile regression; count data; random effects;

    Improving the Sensory, Nutritional and Physicochemical Quality of Fresh Meat

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    The e-book and Special Issue “Improving the Sensory, Nutritional and Physicochemical Quality of Fresh Meat” is composed of six original papers about recent advances in the area of Meat Science about the effect of production system in lamb meat quality, the effect of animal feed supplements in cattle meat, treatment of cattle carcasses to improve tenderness, and the characterization of volatile compounds associated with sensory attributes. Moreover, studies regarding the developments in the processing of meat are also included in this publication

    Editorial: advances in understanding marine heatwaves and their impacts

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    © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Benthuysen, J. A., Oliver, E. C. J., Chen, K., & Wernberg, T. Editorial: advances in understanding marine heatwaves and their impacts. Frontiers in Marine Science, 7, (2020): 147, doi:10.3389/fmars.2020.00147.Editorial on the Research Topic Advances in Understanding Marine Heatwaves and Their Impacts In recent years, prolonged, extremely warm water events, known as marine heatwaves, have featured prominently around the globe with their disruptive consequences for marine ecosystems. Over the past decade, marine heatwaves have occurred from the open ocean to marginal seas and coastal regions, including the unprecedented 2011 Western Australia marine heatwave (Ningaloo Niño) in the eastern Indian Ocean (e.g., Pearce et al., 2011), the 2012 northwest Atlantic marine heatwave (Chen et al., 2014), the 2012 and 2015 Mediterranean Sea marine heatwaves (Darmaraki et al., 2019), the 2013/14 western South Atlantic (Rodrigues et al., 2019) and 2017 southwestern Atlantic marine heatwave (Manta et al., 2018), the persistent 2014–2016 “Blob” in the North Pacific (Bond et al., 2015; Di Lorenzo and Mantua, 2016), the 2015/16 marine heatwave spanning the southeastern tropical Indian Ocean to the Coral Sea (Benthuysen et al., 2018), and the Tasman Sea marine heatwaves in 2015/16 (Oliver et al., 2017) and 2017/18 (Salinger et al., 2019). These events have set new records for marine heatwave intensity, the temperature anomaly exceeding a climatology, and duration, the sustained period of extreme temperatures. We have witnessed the profound consequences of these thermal disturbances from acute changes to marine life to enduring impacts on species, populations, and communities (Smale et al., 2019). These marine heatwaves have spurred a diversity of research spanning the methodology of identifying and quantifying the events (e.g., Hobday et al., 2016) and their historical trends (Oliver et al., 2018), understanding their physical mechanisms and relationships with climate modes (e.g., Holbrook et al., 2019), climate projections (Frölicher et al., 2018), and understanding the biological impacts for organisms and ecosystem function and services (e.g., Smale et al., 2019). By using sea surface temperature percentiles, temperature anomalies can be quantified based on their local variability and account for the broad range of temperature regimes in different marine environments. For temperatures exceeding a 90th-percentile threshold beyond a period of 5-days, marine heatwaves can be classified into categories based on their intensity (Hobday et al., 2018). While these recent advances have provided the framework for understanding key aspects of marine heatwaves, a challenge lies ahead for effective integration of physical and biological knowledge for prediction of marine heatwaves and their ecological impacts. This Research Topic is motivated by the need to understand the mechanisms for how marine heatwaves develop and the biological responses to thermal stress events. This Research Topic is a collection of 18 research articles and three review articles aimed at advancing our knowledge of marine heatwaves within four themes. These themes include methods for detecting marine heatwaves, understanding their physical mechanisms, seasonal forecasting and climate projections, and ecological impacts.We thank the contributing authors, reviewers, and the editorial staff at Frontiers in Marine Science for their support in producing this issue. We thank the Marine Heatwaves Working Group (http://www.marineheatwaves.org/) for inspiration and discussions. This special issue stemmed from the session on Advances in Understanding Marine Heat Waves and Their Impacts at the 2018 Ocean Sciences meeting (Portland, USA)
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