Regulating Drones Under the First and Fourth Amendments

The FAA Modernization and Reform Act of 2012 requires the Federal Aviation Administration to integrate unmanned aerial vehicles (UAVs), or drones, into the national airspace system by September 2015. Yet perhaps because of their chilling accuracy in targeted killings abroad, perhaps because of an increasing consciousness of diminishing privacy more generally, and perhaps simply because of a fear of the unknown, divergent UAV-restrictive legislation has been proposed in Congress and enacted in a number of states. Given UAV utility and cost-effectiveness over a vast range of tasks, however, widespread commercial use ultimately seems certain. Consequently, it is imperative to understand the constitutional restraints on public flight and constitutional protections afforded to private flight. Unfortunately, although there are a few Fourth Amendment precedents in manned aviation, they are mired not only in 1980s technology but also in the 1980s third party doctrine, and therefore do not reflect more recent Fourth Amendment developments and doctrinal fissures. There is also considerable uncertainty over First Amendment protection of information-gathering—for example, is there a right to record? Further, there is no judicial or scholarly analysis of how UAV flight fits within contemporary First Amendment forum doctrine, a framework that provides a useful starting point for analyzing speech restrictions in government-controlled airspace, but that comes with some uncertainties of its own. It is into this thicket that we dive, and fortunately some clarity emerges. Although the Fourth Amendment third party doctrine hopelessly misunderstands privacy and therefore under-protects our security and liberty interests, the Supreme Court’s manned flyover cases can be mined for a sensible public disclosure doctrine that seems agnostic as to the various Fourth Amendment conceptions: we do not typically require only law enforcement to shield its eyes. Of course, both constitutions and legislation can place special restrictions upon law enforcement, and sometimes doing so makes good sense. But as a general Fourth Amendment matter, the officer may do and see as the citizen would. Hence to understand Fourth Amendment regulation, we must understand how the First Amendment limits government restraint on speech-relevant private UAV flight. Here we analyze the developing right to record and apply contemporary forum doctrine to this novel means of speech and information-gathering. If navigable airspace is treated as a limited public forum, as we propose with some qualification, then the Federal Aviation Administration will have significant—though not unlimited—regulatory leeway to evenhandedly burden speech-related UAV activities where doing so would reasonably promote safe unmanned and manned flight operations. The Agency, however, would likely need further congressional action before it can restrict UAV flight based on privacy rather than safety concerns. As the legality and norms of private flight correspondingly take shape, they will inform Fourth Amendment restrictions on government use

The use of think-aloud and instant data analysis in evaluation research: Exemplar and lessons learned

AbstractWhile health information technologies have become increasingly popular, many have not been formally tested to ascertain their usability. Traditional rigorous methods take significant amounts of time and manpower to evaluate the usability of a system. In this paper, we evaluate the use of instant data analysis (IDA) as developed by Kjeldskov et al. to perform usability testing on a tool designed for older adults and caregivers. The IDA method is attractive because it takes significantly less time and manpower than the traditional usability testing methods. In this paper we demonstrate how IDA was used to evaluate usability of a multifunctional wellness tool, discuss study results and lessons learned while using this method. We also present findings from an extension of the method which allows the grouping of similar usability problems in an efficient manner. We found that the IDA method is a quick, relatively easy approach to identifying and ranking usability issues among health information technologies

Best-Possible Unpredictable Proof-of-Stake: An Impossibility and a Practical Design

The proof-of-stake (PoS) protocols have been proposed to eliminate the unnecessary waste of computing power in Bitcoin. Multiple practical and provably secure designs have been developed, such as Ouroboros Praos (Eurocrypt 2018), Snow White (FC 2019) and more. However, an important security property called unpredictability has not been carefully studied in these provably secure PoS. Unpredictability property is critical for PoS since the attackers could use predictability to launch strengthened versions of multiple attacks (e.g., selfish-mining and bribing). Unpredictability has previously been investigated by Brown-Cohen et al.~(EC 2019) in incentive-driven settings. In this paper, we investigate the property in the cryptographic setting, with the goal of achieving the ``best possible\u27\u27 unpredictability for PoS. First, we present an impossibility result for {\em all} proof-of-stake protocols under the \emph{single-extension} design framework. In this framework, each honest player is allowed to extend exactly one chain in each round; the state-of-the-art permissionless PoS protocols (e.g., Praos, Snow White, and more), are all under this single-extension framework. Our impossibility result states that, if a single-extension PoS protocol achieves the best possible unpredictability, then this protocol cannot be proven secure unless more than $73\%$ of stake is honest. Then, to overcome the impossibility result, we introduce a new design framework, called \emph{multi-extension} PoS, which allows each honest player to extend {\em multiple} chains in a round. We develop a novel strategy called ``$D$-distance-greedy\u27\u27 strategy (where $D$ is a positive integer), in which honest players are allowed to extend {\em a set of best chains that are ``close\u27\u27 to the longest chain}. (Of course, malicious players are allowed to behave arbitrarily in the protocol execution.) This ``$D$-distance-greedy\u27\u27 strategy enables us to construct a class of PoS protocols that achieve the best possible unpredictability. Plus, we design a new tiebreak rule for the multi-extension protocol to chose the best chain that can be extended faster. This ensures that the adversary cannot slowdown the chain growth of honest players. Note, these protocols can be proven secure, assuming a much smaller fraction (e.g., 57\%) of stake to be honest. To enable a thorough security analysis in the cryptographic setting, we develop several new techniques. As the players are allowed to extend multiple chains, the analysis of chain growth is highly non-trivial. We introduce a new analysis framework to analyze the chain growth of a multi-extension protocol. To prove the common prefix property, we introduce a new concept called ``virtual chains\u27\u27, and then present a reduction from the regular version of the common prefix to ``common prefix w.r.t. virtual chains\u27\u27

Mixed metal-organic framework mixed-matrix membranes : insights into simultaneous moisture-triggered and catalytic delivery of nitric oxide using cryo-scanning electron microscopy

Funding: This work was supported by the European Research Council grant ADOR (Advanced Grant 787073). The authors acknowledge the EPSRC Light Element Analysis Facility Grant (EP/T019298/1) and the EPSRC Strategic Equipment Resource Grant (EP/R023751/1).The fundamental chemical and structural diversity of metal–organic frameworks (MOFs) is vast, but there is a lack of industrial adoption of these extremely versatile compounds. To bridge the gap between basic research and industry, MOF powders must be formulated into more application-relevant shapes and/or composites. Successful incorporation of varying ratios of two different MOFs, CPO-27-Ni and CuBTTri, in a thin polymer film represents an important step toward the development of mixed MOF mixed-matrix membranes. To gain insight into the distribution of the two different MOFs in the polymer, we report their investigation by Cryo-scanning electron microscopy (Cryo-SEM) tomography, which minimizes surface charging and electron beam-induced damage. Because the MOFs are based on two different metal ions, Ni and Cu, the elemental maps of the MOF composite cross sections clearly identify the size and location of each MOF in the reconstructed 3D model. The tomography run was about six times faster than conventional focused ion beam (FIB)-SEM and the first insights to image segmentation combined with machine learning could be achieved. To verify that the MOF composites combined the benefits of rapid moisture-triggered release of nitric oxide (NO) from CPO-27-Ni with the continuous catalytic generation of NO from CuBTTri, we characterized their ability to deliver NO individually and simultaneously. These MOF composites show great promise to achieve optimal dual NO delivery in real-world medical applications.Publisher PDFPeer reviewe

Case Report The Management of Gas-Filled Eyes in the Emergency Department

Background. Intraocular gas bubbles are commonly used in retinal surgery. There are specific management guidelines that need to be followed to ensure surgical success, and there are also unique ophthalmic and systemic complications that can occur in such patients. Objective. To educate emergency department personnel about important issues in the management of patients who have a gas-filled eye following retinal surgery. Case Report. A patient with a gas-filled eye developed several complications including pain, severe vision loss, high-grade atrioventricular (AV) block, and pneumocephalus. Conclusion. Awareness of potential problems that may arise in patients with gas-filled eyes who present to the emergency department may help minimize morbidity for such patients

Feasibility of aortic valve assessment with low dose prospectively triggered adaptive systolic (PTAS) cardiac computed tomography angiography

Background: Cardiac computed tomography angiography (CTA) is feasible for aortic valve evaluation, but retrospective gated protocols required high radiation doses for aortic valve assessment. A prospectively triggered adaptive systolic (PTAS) cardiac CT protocol was recently described in arrhythmia using second-generation dual-source CT. In this study, we sought to evaluate the feasibility of PTAS CTA to assess the aortic valve at a low radiation dose. Findings: A retrospective cohort of 29 consecutive patients whom underwent PTAS protocols for clinical indications other than aortic valve assessment and whom also received echocardiography within 2 months of CT, was identified. Images were reviewed for aortic valve morphology (tricuspid/bicuspid/prosthetic) and stenosis (AS) by experienced blinded readers. Accuracy versus echocardiography and radiation doses were assessed. All PTAS coronary CTAs were clinically diagnostic with 0 un-evaluable coronary segments. The accuracy of PTAS for aortic valve morphology was 92.6%, and for exclusion of severe AS was 93.1%. Two exams were un-evaluable for the aortic valve due to inadequate number of phases archived for interpretation. Total radiation dose was a median of 2.8 mSv (interquartile range 1.4–4.4 mSv). Conclusions: PTAS CTA protocols using second-generation dual-source CT for aortic valve evaluation are feasible at low doses. This protocol should be investigated further in larger cohorts

EXAFS Structural Determination of the Pt2(P2O5H2)44– Anion in Solution

We present the first structural determination of the Pt2(P2O5H2)44– anion in solution by analyzing the extended X-ray absorption fine structure (EXAFS) spectrum of the Pt LIII edge. The data could be fit with a simple model involving single and multiple scattering paths to near and far P-atoms, bridging O-atoms, and the other Pt-atom in the binuclear complex. A Pt–Pt distance of 2.876(28) Å and a Pt–P bond length of 2.32(4) Å are obtained. These values are in line with distances found in previous X-ray diffraction studies. The assignment of the EXAFS spectrum of the Pt2(P2O5H2)44– anion in its ground state is required for future time-resolved X-ray absorption measurements with the goal of determining the structure and dynamics of the complex in the 1,3A2u excited states

Data-driven Identification of Parametric Governing Equations of Dynamical Systems Using the Signed Cumulative Distribution Transform

This paper presents a novel data-driven approach to identify partial differential equation (PDE) parameters of a dynamical system. Specifically, we adopt a mathematical "transport" model for the solution of the dynamical system at specific spatial locations that allows us to accurately estimate the model parameters, including those associated with structural damage. This is accomplished by means of a newly-developed mathematical transform, the signed cumulative distribution transform (SCDT), which is shown to convert the general nonlinear parameter estimation problem into a simple linear regression. This approach has the additional practical advantage of requiring no a priori knowledge of the source of the excitation (or, alternatively, the initial conditions). By using training data, we devise a coarse regression procedure to recover different PDE parameters from the PDE solution measured at a single location. Numerical experiments show that the proposed regression procedure is capable of detecting and estimating PDE parameters with superior accuracy compared to a number of recently developed machine learning methods. Furthermore, a damage identification experiment conducted on a publicly available dataset provides strong evidence of the proposed method's effectiveness in structural health monitoring (SHM) applications. The Python implementation of the proposed system identification technique is integrated as a part of the software package PyTransKit (https://github.com/rohdelab/PyTransKit)