A Tiling Approach to Counting Inherent Structures in Hard Potential Systems

The number of distinguishable inherent structures of a liquid is the key component to understanding the thermodynamics of glass formers. In the case of hard potential systems such as hard discs, spheres and ellipsoids, an inherent structure corresponds to a collectively jammed configuration. This work develops a tiling based approach to counting inherent structures that constructs packings by combining sets of elementary locally jammed structures but eliminates those final packings that either, do not tile space, or are not collectively jammed, through the use of tile incompatibility rules. The resulting theory contains a number of geometric quantities, such as the number of growth sites on a tile and the number of tile compatibilities that provide insight into the number of inherent structures in certain limits. We also show that these geometric quantities become quite simple in a system of highly confined hard discs.Comment: 12 pages, 2 figures. Accepted for Publication : Journal of Non-Crystalline Solid

Enumeration of distinct mechanically stable disk packings in small systems

We create mechanically stable (MS) packings of bidisperse disks using an algorithm in which we successively grow or shrink soft repulsive disks followed by energy minimization until the overlaps are vanishingly small. We focus on small systems because this enables us to enumerate nearly all distinct MS packings. We measure the probability to obtain a MS packing at packing fraction $\phi$ and find several notable results. First, the probability is highly nonuniform. When averaged over narrow packing fraction intervals, the most probable MS packing occurs at the highest $\phi$ and the probability decays exponentially with decreasing $\phi$. Even more striking, within each packing-fraction interval, the probability can vary by many orders of magnitude. By using two different packing-generation protocols, we show that these results are robust and the packing frequencies do not change qualitatively with different protocols.Comment: 4 pages, 3 figures, Conference Proceedings for X International Workshop on Disordered System

The proposed Caroline ESA M3 mission to a Main Belt Comet

We describe Caroline, a mission proposal submitted to the European Space Agency in 2010 in response to the Cosmic Visions M3 call for medium-sized missions. Caroline would have travelled to a Main Belt Comet (MBC), characterizing the object during a flyby, and capturing dust from its tenuous coma for return to Earth. MBCs are suspected to be transition objects straddling the traditional boundary between volatile–poor rocky asteroids and volatile–rich comets. The weak cometary activity exhibited by these objects indicates the presence of water ice, and may represent the primary type of object that delivered water to the early Earth. The Caroline mission would have employed aerogel as a medium for the capture of dust grains, as successfully used by the NASA Stardust mission to Comet 81P/Wild 2. We describe the proposed mission design, primary elements of the spacecraft, and provide an overview of the science instruments and their measurement goals. Caroline was ultimately not selected by the European Space Agency during the M3 call; we briefly reflect on the pros and cons of the mission as proposed, and how current and future mission MBC mission proposals such as Castalia could best be approached

Couples Coping Through Deployment: Findings From a Sample of National Guard Families

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140037/1/jclp22487.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/140037/2/jclp22487_am.pd

Bayesian Imaging for Radio Interferometry with Score-Based Priors

The inverse imaging task in radio interferometry is a key limiting factor to retrieving Bayesian uncertainties in radio astronomy in a computationally effective manner. We use a score-based prior derived from optical images of galaxies to recover images of protoplanetary disks from the DSHARP survey. We demonstrate that our method produces plausible posterior samples despite the misspecified galaxy prior. We show that our approach produces results which are competitive with existing radio interferometry imaging algorithms.Comment: 10+4 pages, 6 figures, Machine Learning and the Physical Sciences Workshop, NeurIPS 202

Crustal inheritance and a top-down control on arc magmatism at Mount St. Helens

In a subduction zone, the volcanic arc marks the location where magma, generated via flux melting in the mantle wedge, migrates through the crust and erupts. While the location of deep magma broadly defines the arc position, here we argue that crustal structures, identified in geophysical data from the Washington Cascades magmatic arc, are equally important in controlling magma ascent and defining the spatial distribution and compositional variability of erupted material. As imaged by a three-dimensional resistivity model, a broad lower-crustal mush zone containing 3-10% interconnected melt underlies this segment of the arc, interpreted to episodically feed upper-crustal magmatic systems and drive eruptions. Mount St. Helens is fed by melt channeled around a mid-Tertiary batholith also imaged in the resistivity model and supported by potential-field data. Regionally, volcanism and seismicity are almost exclusive of the batholith, while at Mount St. Helens, along its margin, the ascent of viscous felsic melt is enabled by deep-seated metasedimentary rocks. Both the anomalous forearc location and composition of St. Helens magmas are products of this zone of localized extension along the batholith margin. This work is a compelling example of inherited structural control on local stress state and magmatism

Weaving Indigenous knowledge systems and Western sciences in terrestrial research, monitoring and management in Canada: A protocol for a systematic map

Human activities and development have contributed to declines in biodiversity across the globe.Understanding and addressing biodiversity loss will require the mobilization of diverse knowledge systems. While calls for interdisciplinary practices in environmental research date back decades, there has been a more recent push for weaving multiple knowledge systems in environmental research and management, specifically Indigenous knowledge systems (IKS) and Western sciences. The use of multiple knowledge systems in environmental research can improve understanding of socio-ecological connections, build trust in research findings and help implement evidence-based action towards biodiversity conservation. Mobilizing multiple types of knowledge in environmental research and management can be beneficial; however, challenges remain. There is a need to understand how and where studies have woven IKS and Western sciences together in order to learn about frameworks and processes used, and identify best practices. Here, we present a protocol for a systematic map that will examine the extent, range and nature of the published literature that weaves IKS and Western sciences in terrestrial ecosystems research, monitoring and management in Canada. The systematic map will aim to capture all available and relevant studies found in the published academic and grey literature. The search will use standardized search terms across four publication databases, four specialized websites and one web-based search engine. Bibliographies of relevant review articles captured by our search strategy will be cross-checked to identify additional studies. Calls for evidence among professional networks will also complement the search strategy. All searches will be conducted in English. Search results will be reviewed in two stages: (1) title and abstract and (2) full text. All screening decisions at the full-text stage will be included into the map database. The systematic map will use a narrative synthesis approach employing descriptive tables, statistics and figures (including a map with geospatially referenced studies) to summarize findings. Results from this mapping exercise can serve to support environmental research and management efforts working across IKS and Western sciences by highlighting best practices, as well as evidence gaps

Securing Our Economic Future

The American economy is in the midst of a wrenching crisis, one caused by the COVID-19 pandemic and aggravated further by a series of climate-driven natural disasters. While the economy has made some steps towards recovery, the pandemic has laid bare the reality that too many Americans are unable to meet many of their urgent and basic needs. At the same time, it has become painfully clear that American society is not equipped to deal with the risks emerging from our changing climate. This book is a contribution towards policy options for addressing these challenges. Although it was largely written before the pandemic crises beset our country, the analyses, diagnoses, and prescriptions contained within all shed new light on the underlying fragilities that have since been exposed. The volume is composed of nine commissioned chapters and is divided into three sections, covering the 'Economics of the American Middle Class'; the 'Geographic Disparities in Economic Opportunity'; and the 'Geopolitics of the Climate and Energy Challenge and the US Policy Response.' Part I focuses on the economic wellbeing of the American middle class and the chapters in this section evaluate the prevailing narrative of its decline. The chapters in part II investigate the large variation in income and economic opportunities across places, and include a specific policy proposal for emergency rental assistance. Part III is devoted to the global climate crisis. The chapters in this final section emphasize the mounting social and economic costs of inaction and discuss potential policy approaches for tackling the climate challenge

Acute myeloid leukemia induces pro-tumoral p16INK4a driven senescence in the bone marrow microenvironment

Acute myeloid leukemia (AML) is an age-related disease that is highly dependent on the bone marrow (BM) microenvironment. With increasing age, tissues accumulate senescent cells, characterized by an irreversible arrest of cell proliferation and the secretion of a set of proinflammatory cytokines, chemokines, and growth factors, collectively known as the senescence-associated secretory phenotype (SASP). Here, we report that AML blasts induce a senescent phenotype in the stromal cells within the BM microenvironment and that the BM stromal cell senescence is driven by p16INK4a expression. The p16INK4a-expressing senescent stromal cells then feed back to promote AML blast survival and proliferation via the SASP. Importantly, selective elimination of p16INK4a 1 senescent BM stromal cells in vivo improved the survival of mice with leukemia. Next, we find that the leukemia-driven senescent tumor microenvironment is caused by AML-induced NOX2-derived superoxide. Finally, using the p16-3MR mouse model, we show that by targeting NOX2 we reduced BM stromal cell senescence and consequently reduced AML proliferation. Together, these data identify leukemia-generated NOX2-derived superoxide as a driver of protumoral p16INK4a-dependent senescence in BM stromal cells. Our findings reveal the importance of a senescent microenvironment for the pathophysiology of leukemia. These data now open the door to investigate drugs that specifically target the “benign” senescent cells that surround and support AML

The health impacts of waste incineration: a systematic review

Introduction: Waste incineration is increasingly used to reduce waste volume and produce electricity. Several incinerators have recently been proposed in Australia and community groups are concerned about health impacts. An overview of the evidence on health effects has been needed. Method: A systematic review of English language literature for waste incinerators and health using PRISMA methodology. Results: A range of adverse health effects were identified, including significant associations with some neoplasia, congenital anomalies, infant deaths and miscarriage, but not for other diseases. Ingestion was the dominant exposure pathway for the public. Newer incinerator technologies may reduce exposure. Discussion: Despite these findings, diverse chemicals, poor study methodologies and inconsistent reporting of incinerator technology specifications precludes firmer conclusions about safety. Conclusion: Older incinerator technology and infrequent maintenance schedules have been strongly linked with adverse health effects. More recent incinerators have fewer reported ill effects, perhaps because of inadequate time for adverse effects to emerge. A precautionary approach is required. Waste minimisation is essential. Implications for public health: Public health practitioners can offer clearer advice about adverse health effects from incinerators. We suggest improved research design and methods to make future studies more robust and comparable. We offer ideas for better policy and regulation. Key words: waste, health, cancer, incineration, toxi