Structural Analysis and Interpretation of Deformation Along the Keweenaw Fault System West of Lake Gratiot, Keweenaw County, Michigan

The Keweenaw fault is perhaps the most significant fault associated with the Midcontinent Rift System of the north-central United States. The fault, parallel to the south edge of the rift, has been interpreted as a rift-bounding normal fault that was inverted by subsequent compressional events, thrusting copper-bearing Portage Lake Volcanics (~ 1.1 Ga) over younger Jacobsville Sandstone. Geologic maps and cross sections published in the 1950s by the U. S. Geological Survey depict the fault with a well-defined, single, sinuous trace that is locally associated with smaller branch faults. Cross-sections from that time generally show a simple listric stratal geometry for hanging-wall lava flows and variable dip of footwall siliciclastic layers, but with little to no fold definition. New field mapping between Mohawk (MI) and Bête Gris Bay indicates that the Keweenaw fault here is better characterized as a fault system consisting of: 1) segments striking east-northeast with steep northerly dip, 2) segments striking east-southeast also with steep northerly dip, and 3) segments striking north-northeast with moderate-to-shallow westerly dip. The members of these three fault sets define a multistranded Keweenaw fault system and several large fault-bounded blocks of Portage Lake Volcanics. Mapping also revealed folding in hanging-wall Portage Lake Volcanics and has defined fold geometry in footwall Jacobsville Sandstone. Fold axes are generally subparallel to adjacent faults and therefore are probably related to fault movement. Along Bruneau Creek, multiple anticlines and synclines in the footwall of a Set 3 fault and a faulted anticline in the hanging-wall indicate significant shortening across a west-dipping thrust fault. Along the east tributary of Snake Creek, a single syncline in the footwall of a Set 2 fault resulted from tilting of Jacobsville strata to vertical by north-side-up movement of a steeply dipping, right-lateral, strike-slip fault, with minor shortening across the fault. The pattern and relationships of faults and folds in the area are consistent with a fault system dominated by dextral shear rather than by reverse movement as in the currently accepted model. Kinematic slip indicators measured on 55 small faults demonstrate mostly right-lateral strike slip and lesser north-side-up reverse slip, with a 2.5:1 ratio of strike-to-dip slip. Inversion of fault-slip data shows that maximum shortening during faulting was along an azimuth of 285°-105°, suggesting a WNW-ESE maximum paleostress direction that is nearly parallel to expected Grenville or Appalachian orogenic forces. The new mapping and structural analyses in this area have revealed a multistranded Keweenaw fault system that is transpressional in nature, dominated by dextral strike slip, and has lesser reverse slip with north side up. Fault-bounded blocks having ENE-oriented long dimensions generally moved eastward along set 1 and 2 faults, while thrusting Portage Lake Volcanics over Jacobsville Sandstone along set 3 faults. The estimated WNW-ESE maximum shortening direction associated with fault movement strongly suggests that the Grenville Orogeny was primarily responsible for movement of the Keweenaw fault system, with possible reactivation occurring during the Appalachian Orogeny

The Illustrated Masterpiece: Teaching the Artist Biography to Elementary School Children Using the Illustrations in Picture Books

Senior Project submitted to The Division of Arts of Bard College. Arts programs, particularly ones that focus on education, are constantly losing their funding. Even as Michelle Obama, the former First Lady of the United States, stated that “Arts education is not a luxury, it’s a necessity. It’s really the air many of these kids breathe[1]”, programs that benefit these kids are seeing their budgets slashed, and classroom educators are unable to get the training that they need to provide fulfilling educational experiences. In an ideal world, museums would be free to everyone who wants to learn about art, and teachers would be paid at least six figures a year. But since that doesn’t seem to be happening any time soon, it is important for us to find ways to provide kids with wholistic, culturally-rich art experiences within their very own classrooms. I think that picture books could be a way of doing this. There are a surprising amount of picture books that focus on elements of art history. In this case study, I am going to focus on books that tell a biographical story and books that contain illustrations rather than print reproductions of works, because I am interested in the choices that illustrators make to show specific aspects of the artwork, because the biography is one of the major methods of art history, and because I remember, as a child, enjoying illustrated books far more than books with print reproductions (the series of artists biographies by Mike Venezia[2] come to mind). Within this project, I plan on looking at and analyzing several books about four different artists, each a key member in the canon of western art history, and each am artist with a distinct style to learn from. Through looking at these books about Pablo Picasso, Henri Matisse, and Frida Kahlo, I hope to learn about the ways that the illustrators choose to introduce the artists and their unique styles to elementary school audiences, and the ways that these introductions can be implemented within classrooms, even by teachers that have not received extensive training in art history. [1] Evidence. Cultural Learning Alliance. February 16, 2018. Accessed March 22, 2018. https://culturallearningalliance.org.uk/evidence/. [2] The Worlds Greatest Artists. Mike Venezia. Accessed March 22, 2018. http://www.mikevenezia.com/artists/

Absence of Pressure-Driven Supersolid Flow at Low Frequency

An important unresolved question in supersolid research is the degree to which the non-classical rotational inertia (NCRI) phenomenon observed in the torsional oscillator experiments of Kim and Chan, is evidence for a Bose-condensed supersolid state with superfluid-like properties. In an open annular geometry, Kim and Chan found that a fraction of the solid moment of inertia is decoupled from the motion of the oscillator; however, when the annulus is blocked by a partition, the decoupled supersolid fraction is locked to the oscillator being accelerated by an AC pressure gradient generated by the moving partition. These observations are in accord with superfluid hydrodynamics. We apply a low frequency AC pressure gradient in order to search for a superfluid-like response in a supersolid sample. Our results are consistent with zero supersolid flow in response to the imposed low frequency pressure gradient. A statistical analysis of our data sets a bound, at the 68% confidence level, of 9.6$\times 10^{-4}$ nm/s for the mass transport velocity carried by a possible supersolid flow. In terms of a simple model for the supersolid, an upper bound of 3.3$\times 10^{-6}$ is set for the supersolid fraction at 25 mK, at this same confidence level. These findings force the conclusion that the NCRI observed in the torsional oscillator experiments is not evidence for a frequency independent superfluid-like state. Supersolid behavior is a frequency-dependent phenomenon, clearly evident in the frequency range of the torsional oscillator experiments, but undetectably small at frequencies approaching zero.Comment: 6 pages, 5 figure

Why we can’t go back to normal: 5 appeals for a sustainable post-pandemic economy

The pandemic creates much hardship but also shows us how quickly societies can adapt to necessary change, write the members of the University of Hohenheim’s department of innovation economic

A Comparative Study of Population-Graph Construction Methods and Graph Neural Networks for Brain Age Regression

The difference between the chronological and biological brain age of a subject can be an important biomarker for neurodegenerative diseases, thus brain age estimation can be crucial in clinical settings. One way to incorporate multimodal information into this estimation is through population graphs, which combine various types of imaging data and capture the associations among individuals within a population. In medical imaging, population graphs have demonstrated promising results, mostly for classification tasks. In most cases, the graph structure is pre-defined and remains static during training. However, extracting population graphs is a non-trivial task and can significantly impact the performance of Graph Neural Networks (GNNs), which are sensitive to the graph structure. In this work, we highlight the importance of a meaningful graph construction and experiment with different population-graph construction methods and their effect on GNN performance on brain age estimation. We use the homophily metric and graph visualizations to gain valuable quantitative and qualitative insights on the extracted graph structures. For the experimental evaluation, we leverage the UK Biobank dataset, which offers many imaging and non-imaging phenotypes. Our results indicate that architectures highly sensitive to the graph structure, such as Graph Convolutional Network (GCN) and Graph Attention Network (GAT), struggle with low homophily graphs, while other architectures, such as GraphSage and Chebyshev, are more robust across different homophily ratios. We conclude that static graph construction approaches are potentially insufficient for the task of brain age estimation and make recommendations for alternative research directions.Comment: Accepted at GRAIL, MICCAI 202

Atlas-Based Interpretable Age Prediction

Age prediction is an important part of medical assessments and research. It can aid in detecting diseases as well as abnormal ageing by highlighting the discrepancy between chronological and biological age. To gain a comprehensive understanding of age-related changes observed in various body parts, we investigate them on a larger scale by using whole-body images. We utilise the Grad-CAM interpretability method to determine the body areas most predictive of a person's age. We expand our analysis beyond individual subjects by employing registration techniques to generate population-wide interpretability maps. Furthermore, we set state-of-the-art whole-body age prediction with a model that achieves a mean absolute error of 2.76 years. Our findings reveal three primary areas of interest: the spine, the autochthonous back muscles, and the cardiac region, which exhibits the highest importance

A microglial activity state biomarker panel differentiates FTD-granulin and Alzheimer's disease patients from controls

BackgroundWith the emergence of microglia-modulating therapies there is an urgent need for reliable biomarkers to evaluate microglial activation states.MethodsUsing mouse models and human induced pluripotent stem cell-derived microglia (hiMGL), genetically modified to yield the most opposite homeostatic (TREM2-knockout) and disease-associated (GRN-knockout) states, we identified microglia activity-dependent markers. Non-targeted mass spectrometry was used to identify proteomic changes in microglia and cerebrospinal fluid (CSF) of Grn- and Trem2-knockout mice. Additionally, we analyzed the proteome of GRN- and TREM2-knockout hiMGL and their conditioned media. Candidate marker proteins were tested in two independent patient cohorts, the ALLFTD cohort (GRN mutation carriers versus non-carriers), as well as the proteomic data set available from the EMIF-AD MBD study.ResultsWe identified proteomic changes between the opposite activation states in mouse microglia and CSF, as well as in hiMGL cell lysates and conditioned media. For further verification, we analyzed the CSF proteome of heterozygous GRN mutation carriers suffering from frontotemporal dementia (FTD). We identified a panel of six proteins (FABP3, MDH1, GDI1, CAPG, CD44, GPNMB) as potential indicators for microglial activation. Moreover, we confirmed three of these proteins (FABP3, GDI1, MDH1) to be significantly elevated in the CSF of Alzheimer's (AD) patients. Remarkably, each of these markers differentiated amyloid-positive cases with mild cognitive impairment (MCI) from amyloid-negative individuals.ConclusionsThe identified candidate proteins reflect microglia activity and may be relevant for monitoring the microglial response in clinical practice and clinical trials modulating microglial activity and amyloid deposition. Moreover, the finding that three of these markers differentiate amyloid-positive from amyloid-negative MCI cases in the AD cohort suggests that these proteins associate with a very early immune response to seeded amyloid. This is consistent with our previous findings in the Dominantly Inherited Alzheimer's Disease Network (DIAN) cohort, where soluble TREM2 increases as early as 21 years before symptom onset. Moreover, in mouse models for amyloidogenesis, seeding of amyloid is limited by physiologically active microglia further supporting their early protective role. The biological functions of some of our main candidates (FABP3, CD44, GPNMB) also further emphasize that lipid dysmetabolism may be a common feature of neurodegenerative disorders

Body Fat Estimation from Surface Meshes using Graph Neural Networks

Body fat volume and distribution can be a strong indication for a person's overall health and the risk for developing diseases like type 2 diabetes and cardiovascular diseases. Frequently used measures for fat estimation are the body mass index (BMI), waist circumference, or the waist-hip-ratio. However, those are rather imprecise measures that do not allow for a discrimination between different types of fat or between fat and muscle tissue. The estimation of visceral (VAT) and abdominal subcutaneous (ASAT) adipose tissue volume has shown to be a more accurate measure for named risk factors. In this work, we show that triangulated body surface meshes can be used to accurately predict VAT and ASAT volumes using graph neural networks. Our methods achieve high performance while reducing training time and required resources compared to state-of-the-art convolutional neural networks in this area. We furthermore envision this method to be applicable to cheaper and easily accessible medical surface scans instead of expensive medical images

Suppressing ghost beams: Backlink options for LISA

In this article we discuss possible design options for the optical phase reference system, the so called backlink, between two moving optical benches in a LISA satellite. The candidates are based on two approaches: Fiber backlinks, with additional features like mode cleaning cavities and Faraday isolators, and free beam backlinks with angle compensation techniques. We will indicate dedicated ghost beam mitigation strategies for the design options and we will point out critical aspects in case of an implementation in LISA. © Published under licence by IOP Publishing Ltd.DFG/SFB/1128Deutsches Zentrum für Luft- und Raumfahrt (DLR)Bundesministerium für Wirtschaft und Technologie/50 OQ 0601NASA/NNX15AC48