Water Delivery and Giant Impacts in the 'Grand Tack' Scenario

A new model for terrestrial planet formation (Hansen 2009, Walsh et al. 2011) has explored accretion in a truncated protoplanetary disk, and found that such a configuration is able to reproduce the distribution of mass among the planets in the Solar System, especially the Earth/Mars mass ratio, which earlier simulations have generally not been able to match. Walsh et al. tested a possible mechanism to truncate the disk--a two-stage, inward-then-outward migration of Jupiter and Saturn, as found in numerous hydrodynamical simulations of giant planet formation. In addition to truncating the disk and producing a more realistic Earth/Mars mass ratio, the migration of the giant planets also populates the asteroid belt with two distinct populations of bodies--the inner belt is filled by bodies originating inside of 3 AU, and the outer belt is filled with bodies originating from between and beyond the giant planets (which are hereafter referred to as `primitive' bodies). We find here that the planets will accrete on order 1-2% of their total mass from primitive planetesimals scattered onto planet-crossing orbits during the formation of the planets. For an assumed value of 10% for the water mass fraction of the primitive planetesimals, this model delivers a total amount of water comparable to that estimated to be on the Earth today. While the radial distribution of the planetary masses and the dynamical excitation of their orbits are a good match to the observed system, we find that the last giant impact is typically earlier than 20 Myr, and a substantial amount of mass is accreted after that event. However, 5 of the 27 planets larger than half an Earth mass formed in all simulations do experience large late impacts and subsequent accretion consistent with the dating of the Moon-forming impact and the estimated amount of mass accreted by Earth following that event

Inparanoid: a comprehensive database of eukaryotic orthologs

The Inparanoid eukaryotic ortholog database (http://inparanoid.cgb.ki.se/) is a collection of pairwise ortholog groups between 17 whole genomes; Anopheles gambiae, Caenorhabditis briggsae, Caenorhabditis elegans, Drosophila melanogaster, Danio rerio, Takifugu rubripes, Gallus gallus, Homo sapiens, Mus musculus, Pan troglodytes, Rattus norvegicus, Oryza sativa, Plasmodium falciparum, Arabidopsis thaliana, Escherichia coli, Saccharomyces cerevisiae and Schizosaccharomyces pombe. Complete proteomes for these genomes were derived from Ensembl and UniProt and compared pairwise using Blast, followed by a clustering step using the Inparanoid program. An Inparanoid cluster is seeded by a reciprocally best-matching ortholog pair, around which inparalogs (should they exist) are gathered independently, while outparalogs are excluded. The ortholog clusters can be searched on the website using Ensembl gene/protein or UniProt identifiers, annotation text or by Blast alignment against our protein datasets. The entire dataset can be downloaded, as can the Inparanoid program itself

Parenclitic network mapping identifies response to targeted albumin therapy in patients hospitalized with decompensated cirrhosis

BACKGROUND: The efficacy of targeted albumin therapy in the management of decompensatory events in cirrhosis is unclear with different reports showing conflicting results. It is possible that only certain subgroups of patients may benefit from targeted albumin administration. However, extensive conventional subgroup analyses have not yet identified these subgroups. Albumin is an important regulator of physiological networks and may interact with homeostatic mechanism differently in patients according to the integrity of their physiological network. In the present study we aimed to assess the value of network mapping in predicting response to targeted albumin therapy in patients with cirrhosis. METHOD: This is a sub-study of the ATTIRE trial; a multicentre, randomized trial conducted to assess the effect of targeted albumin therapy in cirrhosis. Baseline serum bilirubin, albumin, sodium, creatinine, CRP, and white cell count (WCC), international normalised ratio, heart rate, and blood pressure of 777 patients followed up for 6 months were used for network mapping using parenclitic analysis. Parenclitic network analysis involves measuring the deviation of each individual patient from the existing network of physiological interactions in a reference population. RESULT: Overall network connectivity as well as deviations along WCC-CRP axis predicted 6-month survival independent of age and model for end-stage liver disease (MELD) in the standard care arm. Patients with lower deviation along the WCC-CRP axis showed lower survival in response to targeted albumin administration over 6-month follow-up period. Likewise, patients with higher overall physiological connectivity survived significantly less than the standard care group following targeted albumin infusion. CONCLUSION: The parenclitic network mapping can predict survival of patients with cirrhosis and identify patient subgroups that don't benefit from targeted albumin therapy

A low mass for Mars from Jupiter's early gas-driven migration

Jupiter and Saturn formed in a few million years (Haisch et al. 2001) from a gas-dominated protoplanetary disk, and were susceptible to gas-driven migration of their orbits on timescales of only ~100,000 years (Armitage 2007). Hydrodynamic simulations show that these giant planets can undergo a two-stage, inward-then-outward, migration (Masset & Snellgrove 2001, Morbidelli & Crida 2007, Pierens & Nelson 2008). The terrestrial planets finished accreting much later (Klein et al. 2009), and their characteristics, including Mars' small mass, are best reproduced by starting from a planetesimal disk with an outer edge at about one astronomical unit from the Sun (Wetherill 1978, Hansen 2009) (1 AU is the Earth-Sun distance). Here we report simulations of the early Solar System that show how the inward migration of Jupiter to 1.5 AU, and its subsequent outward migration, lead to a planetesimal disk truncated at 1 AU; the terrestrial planets then form from this disk over the next 30-50 million years, with an Earth/Mars mass ratio consistent with observations. Scattering by Jupiter initially empties but then repopulates the asteroid belt, with inner-belt bodies originating between 1 and 3 AU and outer-belt bodies originating between and beyond the giant planets. This explains the significant compositional differences across the asteroid belt. The key aspect missing from previous models of terrestrial planet formation is the substantial radial migration of the giant planets, which suggests that their behaviour is more similar to that inferred for extrasolar planets than previously thought.Comment: 12 pages, 4 figures + Supplementary Material 46 pages, 10 figure

Combining Through-Thickness Reinforcement and Self-Healing for Improved Damage Tolerance and Durability of Composites

A study was undertaken to develop a prototype method for adding through-thickness hollow glass tubes infused with uncured resin and hardener in a carbon Z-pin through-thickness reinforcement field embedded in a composite laminate. Two types of tube insertion techniques were attempted in an effort to ensure the glass tubes survived the panel manufacturing process. A self-healing resin was chosen with a very low viscosity, two component, liquid epoxy resin system designed to be mixed at a 2-to-1 ratio of epoxy to hardener. IM7/8552 carbon epoxy double cantilever beam (DCB) specimens were cut from the hybrid Z-pin and glass tube reinforced panels and tested. In-situ injection of resin and hardener directly into glass tubes, in a staggered pattern to allow for 2-to-1 ratio mixing, resulted in partial healing of the fracture plane, but only if the injection was performed while the specimen was held at maximum load after initial fracture. Hence, there is some potential for healing delamination via resin and hardener delivered through a network of through-thickness glass tubes, but only if the tubes are connected to a reservoir where additional material may be injected as needed

Microwave Packaging for Superconducting Qubits

Over the past two decades, the performance of superconducting quantum circuits has tremendously improved. The progress of superconducting qubits enabled a new industry branch to emerge from global technology enterprises to quantum computing startups. Here, an overview of superconducting quantum circuit microwave control is presented. Furthermore, we discuss one of the persistent engineering challenges in the field, how to control the electromagnetic environment of increasingly complex superconducting circuits such that they are simultaneously protected and efficiently controllable

Universal access: the benefits and challenges in bringing integrated HIV care to isolated and conflict affected populations in the Republic of Congo

The Pool region of the Republic of Congo is an isolated, conflict-affected area with under-resourced and poorly functioning health care services. Despite significant AIDS-related mortality and morbidity in this area, and a national level commitment to universal HIV care, HIV has been largely neglected. In 2005 Médecins Sans Frontières decided to introduce HIV care activities. However, in this setting of high basic health care needs, limited medical resources and competing medical priorities, a vertical HIV programme was not suitable. This paper describes the process of integrating HIV care and treatment into basic health services, the clinical outcomes of 222 patients started on antiretroviral treatment (ART), and the benefits to communities and health care systems. Key lessons learned include the use of multi-skilled human resources, the step-wise implementation of HIV activities, the initial engagement of an HIV experienced staff member, the use of simplified and adapted testing, clinical and monitoring protocols and drug regimens, the introduction of more complex monitoring tools to simplify clinical management decisions and intensive staff education regarding the benefits of HIV integration. This project in a rural and remote conflict-affected setting demonstrates that integrated HIV programs can save lives and play a key role in helping to achieve universal access to ART in Africa

From the oceans to the cloud: Opportunities and challenges for data, models, computation and workflows.

© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Vance, T. C., Wengren, M., Burger, E., Hernandez, D., Kearns, T., Medina-Lopez, E., Merati, N., O'Brien, K., O'Neil, J., Potemrag, J. T., Signell, R. P., & Wilcox, K. From the oceans to the cloud: Opportunities and challenges for data, models, computation and workflows. Frontiers in Marine Science, 6(211), (2019), doi:10.3389/fmars.2019.00211.Advances in ocean observations and models mean increasing flows of data. Integrating observations between disciplines over spatial scales from regional to global presents challenges. Running ocean models and managing the results is computationally demanding. The rise of cloud computing presents an opportunity to rethink traditional approaches. This includes developing shared data processing workflows utilizing common, adaptable software to handle data ingest and storage, and an associated framework to manage and execute downstream modeling. Working in the cloud presents challenges: migration of legacy technologies and processes, cloud-to-cloud interoperability, and the translation of legislative and bureaucratic requirements for “on-premises” systems to the cloud. To respond to the scientific and societal needs of a fit-for-purpose ocean observing system, and to maximize the benefits of more integrated observing, research on utilizing cloud infrastructures for sharing data and models is underway. Cloud platforms and the services/APIs they provide offer new ways for scientists to observe and predict the ocean’s state. High-performance mass storage of observational data, coupled with on-demand computing to run model simulations in close proximity to the data, tools to manage workflows, and a framework to share and collaborate, enables a more flexible and adaptable observation and prediction computing architecture. Model outputs are stored in the cloud and researchers either download subsets for their interest/area or feed them into their own simulations without leaving the cloud. Expanded storage and computing capabilities make it easier to create, analyze, and distribute products derived from long-term datasets. In this paper, we provide an introduction to cloud computing, describe current uses of the cloud for management and analysis of observational data and model results, and describe workflows for running models and streaming observational data. We discuss topics that must be considered when moving to the cloud: costs, security, and organizational limitations on cloud use. Future uses of the cloud via computational sandboxes and the practicalities and considerations of using the cloud to archive data are explored. We also consider the ways in which the human elements of ocean observations are changing – the rise of a generation of researchers whose observations are likely to be made remotely rather than hands on – and how their expectations and needs drive research towards the cloud. In conclusion, visions of a future where cloud computing is ubiquitous are discussed.This is PMEL contribution 4873