Towards a formalism for mapping the spacetimes of massive compact objects: Bumpy black holes and their orbits

Observations have established that extremely compact, massive objects are common in the universe. It is generally accepted that these objects are black holes. As observations improve, it becomes possible to test this hypothesis in ever greater detail. In particular, it is or will be possible to measure the properties of orbits deep in the strong field of a black hole candidate (using x-ray timing or with gravitational-waves) and to test whether they have the characteristics of black hole orbits in general relativity. Such measurements can be used to map the spacetime of a massive compact object, testing whether the object's multipoles satisfy the strict constraints of the black hole hypothesis. Such a test requires that we compare against objects with the ``wrong'' multipole structure. In this paper, we present tools for constructing bumpy black holes: objects that are almost black holes, but that have some multipoles with the wrong value. The spacetimes which we present are good deep into the strong field of the object -- we do not use a large r expansion, except to make contact with weak field intuition. Also, our spacetimes reduce to the black hole spacetimes of general relativity when the ``bumpiness'' is set to zero. We propose bumpy black holes as the foundation for a null experiment: if black hole candidates are the black holes of general relativity, their bumpiness should be zero. By comparing orbits in a bumpy spacetime with those of an astrophysical source, observations should be able to test this hypothesis, stringently testing whether they are the black holes of general relativity. (Abridged)Comment: 16 pages + 2 appendices + 3 figures. Submitted to PR

Do Seasonal Glucocorticoid Changes Depend on Reproductive Investment? A Comparative Approach in Birds

Animals go through different life history stages such as reproduction, moult, or migration, of which some are more energy-demanding than others. Baseline concentrations of glucocorticoid hormones increase during moderate, predictable challenges and thus are expected to be higher when seasonal energy demands increase, such as during reproduction. By contrast, stress-induced glucocorticoids prioritize a survival mode that includes reproductive inhibition. Thus, many species down-regulate stress-induced glucocorticoid concentrations during the breeding season. Interspecific variation in glucocorticoid levels during reproduction has been successfully mapped onto reproductive investment, with species investing strongly in current reproduction (fast pace of life) showing higher baseline and lower stress-induced glucocorticoid concentrations than species that prioritize future reproduction over current attempts (slow pace of life). Here we test the >glucocorticoid seasonal plasticity hypothesis>, in which we propose that interspecific variation in seasonal changes in glucocorticoid concentrations from the non-breeding to the breeding season will be related to the degree of reproductive investment (and thus pace of life). We extracted population means for baseline (for 54 species) and stress-induced glucocorticoids (for 32 species) for the breeding and the non-breeding seasons from the database >HormoneBase>, also calculating seasonal glucocorticoid changes. We focused on birds because this group offered the largest sample size. Using phylogenetic comparative methods, we first showed that species differed consistently in both average glucocorticoid concentrations and their changes between the two seasons, while controlling for sex, latitude, and hemisphere. Second, as predicted seasonal changes in baseline glucocorticoids were explained by clutch size (our proxy for reproductive investment), with species laying larger clutches showing a greater increase during the breeding season-especially in passerine species. In contrast, changes in seasonal stress-induced levels were not explained by clutch size, but sample sizes were more limited. Our findings highlight that seasonal changes in baseline glucocorticoids are associated with a species' reproductive investment, representing an overlooked physiological trait that may underlie the pace of life

Risk assessment of SARS-CoV-2 in Antarctic wildlife

The coronavirus disease 2019 (COVID-19) pandemic is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This pathogen has spread rapidly across the world, causing high numbers of deaths and significant social and economic impacts. SARS-CoV-2 is a novel coronavirus with a suggested zoonotic origin with the potential for cross-species transmission among animals. Antarctica can be considered the only continent free of SARS-CoV-2. Therefore, concerns have been expressed regarding the potential human introduction of this virus to the continent through the activities of research or tourismto minimise the effects on human health, and the potential for virus transmission to Antarctic wildlife. We assess the reverse-zoonotic transmission risk to Antarcticwildlife by considering the available information on host susceptibility, dynamics of the infection inhumans, and contact interactions between humans and Antarctic wildlife. The environmental conditions in Antarctica seem to be favourable for the virus stability. Indoor spaces such as those at research stations, research vessels or tourist cruise ships could allow for more transmission among humans and depending on their movements between different locations the virus could be spread across the continent. Among Antarctic wildlife previous in silico analyses suggested that cetaceans are at greater risk of infection whereas seals and birds appear to be at a low infection risk. However, caution needed until further research is carried out and consequently, the precautionary principle should be applied. Field researchers handling animals are identified as the human group posing the highest risk of transmission to animals while tourists and other personnel pose a significant risk only when in close proximity (< 5 m) to Antarctic fauna. We highlight measures to reduce the risk as well as identify of knowledge gaps related to this issue.Fil: Barbosa, A.. Museo Nacional de Ciencias Naturales; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Varsani, Arvind. Arizona State University; Estados Unidos. University of Cape Town; SudáfricaFil: Morandini, Virginia. State University of Oregon; Estados UnidosFil: Grimaldi, Wray. No especifíca;Fil: Vanstreels, Ralph E.T.. Institute Research And Rehabilitation Marine Animals; BrasilFil: Diaz, Julia Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Boulinier, Thierry. Université Montpellier II; Francia. Centre National de la Recherche Scientifique; FranciaFil: Dewar, Meagan. Federation University; AustraliaFil: González Acuña, Daniel. Universidad de Concepción; ChileFil: Gray, Rachael. University Of Western Sydney.; AustraliaFil: McMahon, Clive R.. Sydney Institute Of Marine Science; AustraliaFil: Miller, Gary. University of Western Australia; AustraliaFil: Power, Michelle. Macquarie University; AustraliaFil: Gamble, Amandine. University of California; Estados UnidosFil: Wille, Michelle. University Of Western Sydney.; Australi

Ownership of co-creation assets: driving B2B value propositions in the service economy

The benefits of specialization have been driving the rise of the service economy and pushing capability frontiers and economic growth. In service economies, almost any activity, asset, and skill can be bought on competitive markets, making it harder to build competitive advantage on any of those inputs. Against that background, the question emerges what constitutes sustainable value propositions of service providers. Drawing on an emerging stream of research on the non-ownership value of services, we argue that service providers create value by taking on ownership of service assets and thereby transform uncertainty of value creation into economic opportunities. In our view, service providers offer the essential value proposition of transforming their clients’ uncertainty downsides into opportunities related to assets such as vehicles, real estate, equipment and computing platforms. Clients benefit by delegating ownership of assets to the domain of a service provider. In turn, clients can focus their investment on their most promising assets. Service providers create sustainable competitive advantage by assuming ownership and excelling at the management of (a) unique physical assets, (b) unique intangible assets and (c) maintaining an appropriate architecture of social capital through customer relationships and business ecosystems

Recent Advances in Understanding Particle Acceleration Processes in Solar Flares

We review basic theoretical concepts in particle acceleration, with particular emphasis on processes likely to occur in regions of magnetic reconnection. Several new developments are discussed, including detailed studies of reconnection in three-dimensional magnetic field configurations (e.g., current sheets, collapsing traps, separatrix regions) and stochastic acceleration in a turbulent environment. Fluid, test-particle, and particle-in-cell approaches are used and results compared. While these studies show considerable promise in accounting for the various observational manifestations of solar flares, they are limited by a number of factors, mostly relating to available computational power. Not the least of these issues is the need to explicitly incorporate the electrodynamic feedback of the accelerated particles themselves on the environment in which they are accelerated. A brief prognosis for future advancement is offered.Comment: This is a chapter in a monograph on the physics of solar flares, inspired by RHESSI observations. The individual articles are to appear in Space Science Reviews (2011

Innovative solutions to novel drug development in mental health

There are many new advances in neuroscience and mental health which should lead to a greater understanding of the neurobiological dysfunction in neuropsychiatric disorders and new developments for early, effective treatments. To do this, a biomarker approach combining genetic, neuroimaging, cognitive and other biological measures is needed. The aim of this article is to highlight novel approaches for pharmacological and non-pharmacological treatment development. This article suggests approaches that can be taken in the future including novel mechanisms with preliminary clinical validation to provide a toolbox for mechanistic studies and also examples of translation and back-translation. The review also emphasizes the need for clinician-scientists to be trained in a novel way in order to equip them with the conceptual and experimental techniques required, and emphasizes the need for private-public partnership and pre-competitive knowledge exchange. This should lead the way for important new holistic treatment developments to improve cognition, functional outcome and well-being of people with neuropsychiatric disorders