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The COVID-19 pandemic has highlighted a need for better understanding of countries’ vulnerability and resilience to not only pandemics but also disasters, climate change, and other systemic shocks. A comprehensive characterization of vulnerability can inform efforts to improve infrastructure and guide disaster response in the future. In this paper, we propose a data-driven framework for studying countries’ vulnerability and resilience to incident disasters across multiple dimensions of society. To illustrate this methodology, we leverage the rich data landscape surrounding the COVID-19 pandemic to characterize observed resilience for several countries (USA, Brazil, India, Sweden, New Zealand, and Israel) as measured by pandemic impacts across a variety of social, economic, and political domains. We also assess how observed responses and outcomes (i.e., resilience) of the COVID-19 pandemic are associated with pre-pandemic characteristics or vulnerabilities, including (1) prior risk for adverse pandemic outcomes due to population density and age and (2) the systems in place prior to the pandemic that may impact the ability to respond to the crisis, including health infrastructure and economic capacity. Our work demonstrates the importance of viewing vulnerability and resilience in a multi-dimensional way, where a country’s resources and outcomes related to vulnerability and resilience can differ dramatically across economic, political, and social domains. This work also highlights key gaps in our current understanding about vulnerability and resilience and a need for data-driven, context-specific assessments of disaster vulnerability in the future.

Element level digital phased arrays (DPAs) are widely considered the future of a growing number of practical applications. In fact, according to many RF system experts, they have been the future for more than 30 years; but until recently, the packaging and thermal efficiency of electronics has made their adoption slow for SWaP constrained applications. Increases in density, performance and efficiency of microelectronics are creating a paradigm shift in future DoD RF systems toward DPAs. DPAs are known for the multifunction provided by a software-defined array payload. Each element can be used as an "RF pixel" that can be digitally addressed in any combination to form transmit and receive beams for arbitrary functions. DPA’s software defined payloads enable low SWaP platforms to have the unique capabilities to 1) enable multiple RF functions for the same SWaP and 2) reduce lifecycle cost through standardized and scalable architectures. In this paper, we present a number of recent efforts at BAE Systems to bring these considerations into a present reality for the DoD.

Mathworks has developed a CPU surrogate interface for FPGAs using the common AXI bus as used by Xilinx and Altera. This FPGA IP block is instantiated as an optional control port into users base design. The IP block only requires JTAG and a system clock to provide full system test access.

By unknown mechanisms, the symptoms of amyotrophic lateral sclerosis (ALS) seem to spread along neuroanatomical pathways to engulf the motor nervous system. The rate at which symptoms spread is one of the primary drivers of disease progression. One mechanism by which ALS symptoms could spread is by a prion-like propagation of a toxic misfolded protein from cell to cell along neuroanatomic pathways. Proteins that can transmit toxic conformations between cells often can also experimentally transmit disease between individual organisms. To survey the ease with which motor neuron disease (MND) can be transmitted, we injected spinal cord homogenates prepared from paralyzed mice expressing mutant superoxide dismutase 1 (SOD1-G93A and G37R) into the spinal cords of genetically vulnerable SOD1 transgenic mice. From the various models we tested, one emerged as showing high vulnerability. Tissue homogenates from paralyzed G93A mice induced MND in 6 of 10 mice expressing low levels of G85R-SOD1 fused to yellow fluorescent protein (G85R-YFP mice) by 3-11 months, and produced widespread spinal inclusion pathology. Importantly, second passage of homogenates from G93A → G85R-YFP mice back into newborn G85R-YFP mice induced disease in 4 of 4 mice by 3 months of age. Homogenates from paralyzed mice expressing the G37R variant were among those that transmitted poorly regardless of the strain of recipient transgenic animal injected, a finding suggestive of strain-like properties that manifest as differing abilities to transmit MND. Together, our data provide a working model for MND transmission to study the pathogenesis of ALS.

Proteins possess a complex energy landscape with a large number of local minima called conformational substates that are arranged in a hierarchical fashion. Here we discuss experiments aimed at the elucidation of the energy landscape in carbonmonoxy myoglobin (MbCO). In the highest tier of the hierarchy, a few taxonomic substates exist. Because of their small number, these substates are accessible to detailed structural investigations. Spectroscopic experiments are discussed that elucidate the role of protonations of amino acid side chains in creating the substates. The lower tiers of the hierarchy contain a large number of statistical substates. Substate interconversions are observed in the entire temperature range from below 1 K up to the denaturation temperature, indicating a wide spectrum of energy barriers that separate the substates.

For an understanding of the phenomena, the first condition is the introduction of adequate concepts; only with the help of the correct concepts can we really know what has been observed. When we enter a new field, very often new concepts are needed, and these new concepts usually come up in a rather unclear and undeveloped form. Later they are modified, sometimes they are almost completely abandoned and are replaced by better concepts which then, finally, are clear and well defined. Werner Heisenberg (1) Proteins execute and control essentially all functions in living organisms, and they do it elegantly and efficiently, with designs honed by billions of years of evolution. For each protein, we can ask how it performs its specific function. Because there are at least 100,000 different proteins, all important for life, the task to study, characterize, and understand all proteins will take a very long time. There may, however, be a complementary approach to the problem, namely to find general concepts, properties, and laws that characterize proteins and other biomolecules and that may lead to shortcuts in understanding newly discovered systems. The work of Reat and collaborators in this issue of the Proceedings (2) adds new information that bears on both aspects, the detailed function of a particular protein and insight into general concepts. Reat and coworkers study the dynamics of bacteriorhodopsin (BR) with neutron scattering and hydrogen-deuterium exchange. BR is a protein that converts light into energy by pumping protons across a membrane (3). It consists of seven closely packed, essentially parallel, α helices that tightly enclose a retinal. Light is absorbed by the retinal and, through conformational changes, transports a proton (p) from the cytosolic to the extracellular side of the membrane. This process cannot be static; the proton transport requires motions of the …

When modulated through the harmonic motion of one mirror, the counterpropagating waves in a ring laser oscillate out of phase. A solution to the wave equation is presented that satisfies both the time-dependent boundary condition and the resonance condition. This theoretical prediction is confirmed experimentally to leading order in terms that are inversely proportional to the speed of light. The method of solution is applicable to arbitrary phase modulation at more than one spatial location in the cavity. Potential uses include the reduction of the locking problem in ring lasers and the testing of higher-order kinematic effects in the theory of relativity.