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This paper introduces a novel Functional Graph Convolutional Network (funGCN) framework that combines Functional Data Analysis and Graph Convolutional Networks to address the complexities of multi-task and multi-modal learning in digital health and longitudinal studies. With the growing importance of health solutions to improve health care and social support, ensure healthy lives, and promote well-being at all ages, funGCN offers a unified approach to handle multivariate longitudinal data for multiple entities and ensures interpretability even with small sample sizes. Key innovations include task-specific embedding components that manage different data types, the ability to perform classification, regression, and forecasting, and the creation of a knowledge graph for insightful data interpretation. The efficacy of funGCN is validated through simulation experiments and a real-data application.

We present the first integrated light, TESS-based light curves for star clusters in the Milky Way, Small Magellanic Cloud, and Large Magellanic Cloud. We explore the information encoded in these light curves, with particular emphasis on variability. We describe our publicly available package ELK, which is designed to extract the light curves by applying principal component analysis to perform background light correction, and incorporating corrections for TESS systematics, allowing us to detect variability on time scales shorter than ~10 days. We perform a series of checks to ensure the quality of our light curves, removing observations where systematics are identified as dominant features, and deliver light curves for 348 previously-cataloged open and globular clusters. Where TESS has observed a cluster in more than one observing sectors, we provide separate light curves for each sector (for a total of 2204 light curves). We explore in detail the light curves of star clusters known to contain high-amplitude Cepheid and RR Lyrae variable stars, and confirm that the variability of these known variables is still detectable when summed together with the light from thousands of other stars. We also demonstrate that even some low-amplitude stellar variability is preserved when integrating over a stellar population., Comment: 17 pages, 9 Figures, 3 Tables, Accepted to AAS Journals

X-ray polarization from the Imaging X-ray Polarimetry Explorer (IXPE) provides an important new probe of the geometry of the pulsar emission zone and of particle acceleration in the surrounding pulsar wind nebula (PWN). However, with IXPE's modest ~20-30" spatial resolution, separation of the pulsar signal from the nebula is a challenge. Conventional analysis defines an "off" phase window as pure nebular emission and subtracts its polarization to isolate the phase-varying pulsar ("on-off fitting"). We present a more sensitive scheme that uses external measurements of the nebula structure and pulsar light curve to isolate their contributions to the phase- and spatially-varying polarization via least-squares regression ("simultaneous fitting"). Tests with simulation data show ~30% improvement in pulse phase polarization uncertainties, decreased background systematics, and substantially improved nebular polarization maps. Applying "simultaneous fitting" to early IXPE Crab data extracts additional phase bins with significant polarization. These bins show interesting departures from the well-known optical polarization sweeps, although additional exposure will be needed for precise model confrontation., Comment: 7 pages, 6 figures

In the next decade, the demands for computing in large scientific experiments are expected to grow tremendously. During the same time period, CPU performance increases will be limited. At the CERN Large Hadron Collider (LHC), these two issues will confront one another as the collider is upgraded for high luminosity running. Alternative processors such as graphics processing units (GPUs) can resolve this confrontation provided that algorithms can be sufficiently accelerated. In many cases, algorithmic speedups are found to be largest through the adoption of deep learning algorithms. We present a comprehensive exploration of the use of GPU-based hardware acceleration for deep learning inference within the data reconstruction workflow of high energy physics. We present several realistic examples and discuss a strategy for the seamless integration of coprocessors so that the LHC can maintain, if not exceed, its current performance throughout its running., Comment: 26 pages, 7 figures, 2 tables

Cells offer numerous inspiring examples where proteins and membranes combine to form complex structures that are key to intracellular compartmentalization, cargo transport, and specialization of cell morphology. Despite this wealth of examples, we still lack the design principles to control membrane morphology in synthetic systems. Here we show that even the relatively simple case of spherical nanoparticles binding to lipid-bilayer membrane vesicles results in a remarkably rich set of morphologies that can be controlled quantitatively via the particle binding energy. We find that when the binding energy is weak relative to a characteristic membrane-bending energy, the vesicles adhere to one another and form a soft solid, which could be used as a useful platform for controlled release. When the binding energy is larger, the vesicles undergo a remarkable destruction process consisting first of invaginated tubules, followed by vesicles turning inside-out, yielding a network of nanoparticle-membrane tubules. We propose that the crossover from one behavior to the other is triggered by the transition from partial to complete wrapping of nanoparticles. This model is confirmed by computer simulations and by quantitative estimates of the binding energy. These findings open the door to a new class of vesicle-based, closed-cell gels that are more than 99% water and can encapsulate and release on demand. Our results also show how to intentionally drive dramatic shape changes in vesicles as a step toward shape-responsive particles. Finally, they help us to unify the wide range of previously observed responses of vesicles and cells to added nanoparticles., Comment: 13 pages, 8 figures, and supplemental materials

A crystal lattice, when confined to the surface of a cylinder, must have a periodic structure that is commensurate with the cylinder circumference. This constraint can frustrate the system, leading to oblique crystal lattices or to structures with a chiral seam known as a "line slip" phase, neither of which are stable for isotropic particles in equilibrium on flat surfaces. In this study, we use molecular dynamics simulations to find the steady-state structure of spherical particles with short-range repulsion and long-range attraction far below the melting temperature. We vary the range of attraction using the Lennard-Jones and Morse potentials and find that a shorter-range attraction favors the line-slip. We develop a simple model based only on geometry and bond energy to predict when the crystal or line-slip phases should appear, and find reasonable agreement with the simulations. The simplicity of this model allows us to understand the influence of the commensurability constraint, an understanding that might be extended into the more general problem of self-assembling particles in strongly confined spaces., Comment: 12 pages, 9 figures. Submitted for publication, 2013

We study current-voltage (V-I) characteristics of short superconducting nanowires of length ~ 100 nm exposed to microwave radiation of frequencies between 100 MHz and 15 GHz. The radiation causes a decrease of the average switching current of the wire. This suppression of the switching current is modeled assuming that there is one-to-one correspondence between Little's phase slips and the experimentally observed switching events. At some critical power P* of the radiation a dissipative dynamic superconducting state occurs as an extra step on the V-I curve. It is identified as a phase slip center (PSC). With the dependence of the switching currents and the standard deviations observed at the transitions (i) from a constant supercurrent state to a normal state and (ii) from a constant superconducting state to a PSC state, we conclude that both of the two types of the switching events are triggered by the same microscopic event, namely a single Little's phase slip. We show that the Skocpol-Beasely-Tinkham model is not applicable to our microwave-driven phase slip centers, since it leads to an unphysical small estimated value of the size of the dissipative core of the PSC. Through the analysis of the witching current distributions at a sufficiently low temperature, we also present evidence that the quantum phase slip play a role in switching events under microwaves., Comment: 26 pages, 14 figures, 1 table

Quantum phase slippage (QPS) in a superconducting nanowire is a new candidate for developing a quantum bit. It has also been theoretically predicted that the occurrence of QPS significantly changes the current-phase relationship (CPR) of the wire due to the tunneling between topologically different metastable states. We present studies on the microwave response of the superconducting nanowires to reveal their CPRs. First, we demonstrate a simple nanowire fabrication technique, based on commercially available adhesive tapes, which allows making thin superconducting wire from different metals. We compare the resistance vs. temperature curves of Mo$_{76}$Ge$_{24}$ and Al nanowires to the classical and quantum models of phase slips. In order to describe the experimentally observed microwave responses of these nanowires, we use the McCumber-Stewart model, which is generalized to include either classical or quantum CPR., Comment: to be published in Nano Letters

Microwave response of S-shaped Bi$_2$Sr$_2$CaCu2O$_{8+x}$ (Bi-2212) micron-scale samples, in which the supercurrent was forced to flow perpendicular to the crystal layers, was investigated. A treatment with a focused ion beam allowed us to reduce the plasma frequency down to $f_p$$\sim$5 GHz at $T$=0.3 K in naturally stacked Josephson junctions in a crystal. We observed Shapiro steps at frequencies as low as $\sim$5 GHz. Well-developed zero-crossing Shapiro steps were observed at frequencies as low as $\sim$10 GHz. They appeared as constant-voltage plateaus with a non-zero voltage occurring at zero bias current. We confirmed that zero-crossing Shapiro steps in the Bi-2212 stacked junctions can be observed when the irradiated frequency is sufficiently larger than $f_p$. The observed high-order fractional steps in the microwave responses indicate that the interlayer-coupled Bi-2212 Josephson junctions have nonsinusoidal current-phase relation. Based on the temperature dependence of the steps we also showed that the finite slope of the steps is due to the enhancement of the phase diffusion effect., Comment: accepted in Phys. Rev. B

We establish the superconductor-insulator phase diagram for quasi-one dimensional wires by measuring a large set of MoGe nanowires. This diagram is consistent with the Chakravarty-Schmid-Bulgadaev phase boundary, namely with the critical resistance being equal to R_Q = h/4e^2. We find that transport properties of insulating nanowires exhibit a weak Coulomb blockade behavior., Comment: 5 pages, 4 figures

We study the mobility of extended objects (rods) on a spherical liquid-liquid interface to show how this quantity is modified in a striking manner by both the curvature and the topology of the interface. We present theoretical calculations and experimental measurements of the interfacial fluid velocity field around a moving rod bound to the crowded interface of a water-in-oil droplet. By using different droplet sizes, membrane viscosities, and rod lengths, we show that the viscosity mismatch between the interior and exterior fluids leads to a suppression of the fluid flow on small droplets that cannot be captured by the flat interface predictions., Comment: 4 pages, 3 figures

The University of Houston-Clear Lake has developed a systematic design process to use in facilitating the development of online distance education courses. The process incorporates three semesters, during which faculty members have the opportunity to consult with a design team that consists of instructional designers, World Wide Web developers, graphic artists, media specialists, and instructional programmers. This paper presents an outline of the process, describes each step in detail, and provides a framework for formative evaluation. The first section of the paper considers the theoretical background of the process. The design team is described in the second section, including the members of the team and process management. The pre-production, production, and post-production stages of the process are detailed in the third section. (Author/MES)

The spontaneous assembly of particles in suspension provides a strategy for inexpensive fabrication of devices with nanometer-scale control, such as single-electron transistors for memory or logic applications. A scaleable and robust method to form electrodes with the required nanometer-scale spacing, however, remains a major challenge. Here, we demonstrate a straightforward assembly approach in which metallic colloidal spheres serve as the electrodes. The devices are formed by assembly in suspension followed by deposition onto a patterned substrate. The key to this approach is that the inter-electrode (inter-sphere) spacing is spontaneously set to allow tunneling contact with a single layer of nanoparticles. The measured current exhibits the Coulomb blockade owing to the small size and large electrostatic charging energy of the nanoparticles. We show that the device resistance can be tuned by means of a gate electrode. Our results demonstrate an altogether new approach to inexpensive and large-scale fabrication of electronic devices such as transistors with nanometer-scale features., Comment: 7 pages, 3 figures

We describe experimental investigations of the structure of two-dimensional spherical crystals. The crystals, formed by beads self-assembled on water droplets in oil, serve as model systems for exploring very general theories about the minimum energy configurations of particles with arbitrary repulsive interactions on curved surfaces. Above a critical system size we find that crystals develop distinctive high-angle grain boundaries, or scars, not found in planar crystals. The number of excess defects in a scar is shown to grow linearly with the dimensionless system size. The observed slope is expected to be universal, independent of the microscopic potential., Comment: 4 pages, 3 eps figs (high quality images available from Mark Bowick)

This report identifies the special measures needed to protect the rights and meet the needs of victims of a large-scale terrorist attack involving mass casualties. In particular, it demonstrates efforts required to ensure an effective response to victims' rights and their short- and long-term emotional and psychological needs as an integral part of a comprehensive response to terrorism cases involving mass casualties. The report is based upon the experiences of the Office for Victims of Crime (OVC) in working with victims and providing resources for assistance. The report begins with background information addressing the victims' needs that emerged during the immediate crisis of the Oklahoma City bombing, the postcrisis victim needs after the immediate crisis was dealt with, victims' needs during the criminal justice process, and the long-term victim needs that developed over time. These sections are followed by a discussion of the laws that require victims' rights and services to be part of any crisis response plan. The final sections identify the lessons learned as a result of the Oklahoma City bombing and the other terrorism events that followed it and present policy recommendations that promote future preparedness. (Contains 17 references.) (GCP)