Machine learning with the hierarchy‐of‐hypotheses (HoH) approach discovers novel pattern in studies on biological invasions

Research synthesis on simple yet general hypotheses and ideas is challenging in scientific disciplines studying highly context‐dependent systems such as medical, social, and biological sciences. This study shows that machine learning, equation‐free statistical modeling of artificial intelligence, is a promising synthesis tool for discovering novel patterns and the source of controversy in a general hypothesis. We apply a decision tree algorithm, assuming that evidence from various contexts can be adequately integrated in a hierarchically nested structure. As a case study, we analyzed 163 articles that studied a prominent hypothesis in invasion biology, the enemy release hypothesis. We explored if any of the nine attributes that classify each study can differentiate conclusions as classification problem. Results corroborated that machine learning can be useful for research synthesis, as the algorithm could detect patterns that had been already focused in previous narrative reviews. Compared with the previous synthesis study that assessed the same evidence collection based on experts' judgement, the algorithm has newly proposed that the studies focusing on Asian regions mostly supported the hypothesis, suggesting that more detailed investigations in these regions can enhance our understanding of the hypothesis. We suggest that machine learning algorithms can be a promising synthesis tool especially where studies (a) reformulate a general hypothesis from different perspectives, (b) use different methods or variables, or (c) report insufficient information for conducting meta‐analyses

Stakeholder Perceptions of Current Planning, Assessment and Science Initiatives in Canada’s Beaufort Sea

Over the past 30 years, the Beaufort Sea has been the site of many regional studies and planning efforts. Currently, three major initiatives are underway: the Integrated Regional Impact Study, which focuses on science; the Integrated Ocean Management Plan; and the Beaufort Regional Environmental Assessment. Despite the mounting pressures for offshore energy development in the region, little attention has been given to whether these initiatives facilitate a more coordinated and informed approach to planning, assessment, and decision making for such development. We examined stakeholder perceptions of the existing initiatives to ascertain whether and how they enable horizontal and vertical integration and how effectively they facilitate marine resource planning and decision making. The results show that three essentials of a more coordinated regional approach to planning for marine resources and offshore development are horizontal integration between management bodies, vertical integration from the strategic level and regional scale to the operational level and project scale, and an overarching vision for regional planning and development in the Beaufort Sea.Ces 30 dernières années, la mer de Beaufort a fait l’objet de nombreuses études régionales et de nombreux efforts de planification régionaux. En ce moment, trois grandes initiatives sont en cours : l’étude intégrée d’impact régional, qui est axée sur la science; le plan intégré de gestion de l’océan; et l’Évaluation environnementale régionale de Beaufort. Même si les pressions exercées en vue de la mise en valeur énergétique au large de cette région se font de plus en plus grandes, peu d’attention a été accordée à la possibilité de déterminer si ces initiatives facilitent une approche plus coordonnée et informée en matière de planification, d’évaluation et de prise de décisions relativement à une telle mise en valeur. Nous avons examiné les perceptions des diverses parties prenantes afin d’établir si et comment elles donnent lieu à l’intégration verticale et horizontale, et dans quelle mesure elles favorisent la planification des ressources de la mer et la prise de décisions à leur sujet. Selon les résultats, une approche régionale plus coordonnée en matière de planification des ressources de la mer et de mise en valeur au large comporte trois éléments essentiels, soit : l’intégration horizontale des organismes de gestion; l’intégration verticale, du niveau stratégique et de l’échelle régionale jusqu’au niveau opérationnel et à l’échelle du projet; et une vision déterminante en matière de planification régionale et de mise en valeur de la mer de Beaufort

Bone mineral density optimisation in adults with perinatally acquired HIV infection in routine care

We report on BMD and factors associated with reductions in BMD for all adults with perinatally acquired HIV who attended a London clinic between May 2014 and October 2016. We observed a high prevalence of reductions in BMD and a higher than expected prevalence of factors associated with adverse bone health, namely vitamin D deficiency

Bone mineral density optimisation in adults with perinatally acquired HIV infection in routine care.

We report on BMD and factors associated with reductions in BMD for all adults with perinatally acquired HIV who attended a London clinic between May 2014 and October 2016. We observed a high prevalence of reductions in BMD and a higher than expected prevalence of factors associated with adverse bone health, namely vitamin D deficiency

A contribution to the second neighborhood problem

Seymour's Second Neighborhood Conjecture asserts that every digraph (without digons) has a vertex whose first out-neighborhood is at most as large as its second out-neighborhood. It is proved for tournaments, tournaments missing a matching and tournaments missing a generalized star. We prove this conjecture for classes of digraphs whose missing graph is a comb, a complete graph minus 2 independent edges, or a complete graph minus the edges of a cycle of length 5

The Suprafroth (Superconducting Froth)

The structure and dynamics of froths have been subjects of intense interest due to the desire to understand the behaviour of complex systems where topological intricacy prohibits exact evaluation of the ground state. The dynamics of a traditional froth involves drainage and drying in the cell boundaries, thus it is irreversible. We report a new member to the froths family: suprafroth, in which the cell boundaries are superconducting and the cell interior is normal phase. Despite very different microscopic origin, topological analysis of the structure of the suprafroth shows that statistical von Neumann and Lewis laws apply. Furthermore, for the first time in the analysis of froths there is a global measurable property, the magnetic moment, which can be directly related to the suprafroth structure. We propose that this suprafroth is a new, model system for the analysis of the complex physics of two-dimensional froths

Iron absorption from ferrous fumarate in adult women is influenced by ascorbic acid but not by Na2EDTA

Ascorbic acid and Na2EDTA enhance Fe absorption from the water-soluble Fe compound FeSO4 but their effect on poorly water-soluble Fe compounds such as ferrous fumarate is less well established. In the present study, the effects of ascorbic acid and Na2EDTA on Fe absorption from ferrous fumarate were evaluated in adult women (ten women/study) from the erythrocyte incorporation of Fe stable isotopes (57Fe or 58Fe) 14 d after administration. Two separate studies were made with test meals of Fe-fortified infant cereal (5 mg Fe/meal). Data were evaluated by paired t tests and the results are presented as geometric means. In study 1a, the comparison between Fe absorption from ferrous fumarate- and FeSO4-fortified cereal showed that adult women absorb Fe as well from ferrous fumarate as from FeSO4 (3·0 and 3·1 % respectively, P=0·85). After addition of Na2EDTA (Na2EDTA:fortification Fe molar ratio of 1:1), Fe absorption from FeSO4 was significantly higher than from ferrous fumarate (5·3 v. 3·3 % respectively, P<0·01; study 1b). In study 2, Fe absorption was compared from ferrous fumarate-fortified meals with and without ascorbic acid added at a 4:1 molar ratio (relative to fortification Fe) and the results showed that ascorbic acid increased Fe absorption from ferrous fumarate significantly (6·3 v. 10·4 %, P=0·02). The results of the present studies show that Fe absorption from ferrous fumarate is enhanced by ascorbic acid but not by Na2EDTA, thus emphasising that not all findings from Fe absorption studies made with FeSO4 can be extrapolated to Fe compounds with different solubility propertie

Beyond advocacy: making space for conservation scientists in public debate

The topic of advocacy by scientists has been debated for decades, yet there is little agreement about whether scientists can or should be advocates. The fear of crossing a line into advocacy continues to hold many scientists back from contributing to public discourse, impoverishing public debate about important issues. We believe that progress in this debate is limited by a misconception about the relationship between scientific integrity and objectivity. We begin by unpacking this relationship and debunking three common misconceptions about advocacy by scientists: namely, that advocacy is harmful to scientific credibility, beyond the scope of science, and incompatible with science, which is value-free. We propose new ways of thinking about responsible advocacy by conservation scientists, drawing on practices from the health sciences, where researchers and professional bodies are empowered to act as health advocates.In so doing, we hope to open further space for conservation scientists to actively and legitimately engage in public debate about conservation issues

Calculation of coercivity of magnetic nanostructures at finite temperatures

We report a finite temperature micromagnetic method (FTM) that allows for the calculation of the coercive field of arbitrary shaped magnetic nanostructures at time scales of nanoseconds to years. Instead of directly solving the Landau-Lifshitz-Gilbert equation, the coercive field is obtained without any free parameter by solving a non linear equation, which arises from the transition state theory. The method is applicable to magnetic structures where coercivity is determined by one thermally activated reversal or nucleation process. The method shows excellent agreement with experimentally obtained coercive fields of magnetic nanostructures and provides a deeper understanding of the mechanism of coercivity.Comment: submitted to Phys. Rev.