cssi/SciSciGPT-SciSciNet huggingface dataset:
Health Departments' Engagement in Emergency Preparedness Activities: The Influence of Health Informatics Capacity.

Background Local health departments (LHDs) operate in a complex and dynamic public health landscape, with changing demands on their emergency response capacities. Informatics capacities might play an instrumental role in aiding LHDs emergency preparedness. This study aimed to explore the extent to which LHDs’ informatics capacities are associated with their activity level in emergency preparedness and to identify which health informatics capacities are associated with improved emergency preparedness. Methods We used the 2013 National Profile of LHDs study to perform Poisson regression of emergency preparedness activities. Results Only 38.3% of LHDs participated in full-scale exercises or drills for an emergency in the 12 months period prior to the survey, but a much larger proportion provided emergency preparedness training to staff (84.3%), and/or participated in tabletop exercises (76.4%). Our multivariable analysis showed that after adjusting for several resource-related LHD characteristics, LHDs with more of the 6 information systems still tend to have slightly more preparedness activities. In addition, having a designated emergency preparedness coordinator, and having one or more emergency preparedness staff were among the most significant factors associated with LHDs performing more emergency preparedness activities. Conclusion LHDs might want to utilize better health information systems and information technology tools to improve their activity level in emergency preparedness, through improved information dissemination, and evidence collection.
Locating and Detecting Arrays for Interaction Faults.

The identification of interaction faults in component-based systems has focused on indicating the presence of faults, rather than their location and magnitude. While this is a valuable step in screening a system for interaction faults prior to its release, it provides little information to assist in the correction of such faults. Consequently tests to reveal the location of interaction faults are of interest. The problem of nonadaptive location of interaction faults is formalized under the hypothesis that the system contains (at most) some number d of faults, each involving (at most) some number t of interacting factors. Restrictions on the number and size of the putative faults lead to numerous variants of the basic problem. The relationships between this class of problems and interaction testing using covering arrays to indicate the presence of faults, designed experiments to measure and model faults, and combinatorial group testing to locate faults in a more general testing scenario, are all examined. While each has some definite similarities with the fault location problems for component-based systems, each has some striking differences as well. In this paper, we formulate the combinatorial problems for locating and detecting arrays to undertake interaction fault location. Necessary conditions for existence are established, and using a close connection to covering arrays, asymptotic bounds on the size of minimal locating and detecting arrays are established. A final version of this paper appears in J Comb Optim (2008) 15: 17-48.
On the capacity regions of single-channel and multi-channel full-duplex links

We study the achievable capacity regions of fall-duplex links in the single- and multi-channel cases (in the latter case, the channels are assumed to be orthogonal - e.g., OFDM). We present analytical results that characterize the uplink and downlink capacity region and efficient algorithms for computing rate pairs at the region's boundary. We also provide near-optimal and heuristic algorithms that "convexify" the capacity region when it is not convex. The convexified region corresponds to a combination of a few full-duplex rates (i.e., to time sharing between different operation modes). The algorithms can be used for theoretical characterization of the capacity region as well as for resource (time, power, and channel) allocation with the objective of maximizing the sum of the rates when one of them (uplink or downlink) must be guaranteed (e.g., due to QoS considerations). We numerically illustrate the capacity regions and the rate gains (compared to time division duplex) for various channel and cancellation scenarios. The analytical results provide insights into the properties of the full-duplex capacity region and are essential for future development of scheduling, channel allocation, and power control algorithms.
Synthesis of [11C]MK-1064 as a new PET radioligand for imaging of orexin-2 receptor

The reference standard MK-1064 {5″-chloro-N-((5,6-dimethoxypyridin-2-yl)methyl)-[2,2':5',3″-terpyridine]-3'-carboxamide} was synthesized from methyl 2-chloro-5-iodonicotinate and 5-(chloropyridin-3-yl)boronic acid in 4 steps with 33% overall chemical yield. The precursor desmethyl-MK-1064 {5″-chloro-N-((5-hydroxy-6-methoxypyridin-2-yl)methyl)-[2,2':5',3″-terpyridine]-3'-carboxamide} for radiolabeling was synthesized from 2-bromopyridin-3-ol and 5″-chloro-[2,2':5',3″-terpyridine]-3'-carboxylic acid in 6 steps with 17% overall chemical yield. The target tracer [(11)C]MK-1064 {5″-chloro-N-((5-[(11)C]methoxy-6-methoxypyridin-2-yl)methyl)-[2,2':5',3″-terpyridine]-3'-carboxamide} was prepared by O-[(11)C]methylation of its corresponding precursor desmethyl-MK-1064 with [(11)C]CH3OTf under basic condition and isolated by a simplified solid-phase extraction (SPE) method in 50-60% decay corrected radiochemical yields based on [(11)C]CO2 at end of bombardment (EOB). The overall synthesis time from EOB was 23min, the radiochemical purity was >99%, and the specific activity at end of synthesis (EOS) was 185-555GBq/μmol.
Implicit buffer overflow protection using memory segregation

Computing systems continue to be plagued by malicious corruption of instructions and data. Buffer overflows, in particular, are often employed to disrupt the control flow of vulnerable processes. Existing methods of protection against these attacks operate by detecting corruption after it has taken place or by ensuring that if corruption has taken place, it cannot be used to hijack a process' control flow. These methods thus still allow the corruption of control data to occur but rather than being subverted, the process may terminate or take some other defined error. Few methods have attempted to prevent the corruption of control data, and those that have only focused on preventing the corruption of the return address. We propose the use of multiple memory segments to support multiple stacks, heaps, .bss, and .data sections per process with the goal of segregating control and non-control data. By segregating these different forms of data, we can prevent the corruption of control data by overflow and address manipulation of memory allocated for non-control data. We show that the creation of these additional data segments per process can be implemented through modifications to the compiler.
Enhanced four-wave mixing with nonlinear plasmonic metasurfaces

Plasmonic metasurfaces provide an effective way to increase the efficiency of several nonlinear processes while maintaining nanoscale dimensions. In this work, nonlinear metasurfaces based on film-coupled silver nanostripes loaded with Kerr nonlinear material are proposed to achieve efficient four-wave mixing (FWM). Highly localized plasmon resonances are formed in the nanogap between the metallic film and nanostripes. The local electric field is dramatically enhanced in this subwavelength nanoregion. These properties combined with the relaxed phase matching condition due to the ultrathin area lead to a giant FWM efficiency, which is enhanced by nineteen orders of magnitude compared to a bare silver screen. In addition, efficient visible and low-THz sources can be constructed based on the proposed nonlinear metasurfaces. The FWM generated coherent wave has a directional radiation pattern and its output power is relatively insensitive to the incident angles of the excitation sources. This radiated power can be further enhanced by increasing the excitation power. The dielectric nonlinear material placed in the nanogap is mainly responsible for the ultrastrong FWM response. Compact and efficient wave mixers and optical sources spanning different frequency ranges are envisioned to be designed based on the proposed nonlinear metasurface designs.
Interactive compression for product distributions

We study the interactive compression problem: Given a two-party communication protocol with small information cost, can it be compressed so that the total number of bits communicated is also small? We consider the case where the parties have inputs that are independent of each other, and give a simulation protocol that communicates I^2 * polylog(I) bits, where I is the information cost of the original protocol. Our protocol is the first simulation protocol whose communication complexity is bounded by a polynomial in the information cost of the original protocol.
Steiner reducing sets of minimum weight triangulations

This paper defines and classifies the topology of the Steiner reducing set corresponding to a finite planar point set and its minimum weight triangulation. A Steiner point P is a Steiner reducing point of a planar point set X if the weight (sum of edge lengths) of a minimum weight triangulation of X ? { P } is less than that of X. The Steiner reducing set St ( X ) is the collection of all Steiner reducing points of X. We prove a structure theorem providing alternate geometric conditions for membership in the Steiner reducing set. We prove that St ( X ) can be topologically complex, containing multiple connected components or even holes. We construct families of sets X for which the number of connected components of St ( X ) grows linearly in the cardinality of X. Moreover, we prove that when St ( X ) is not simply connected, the rank of H 1 ( St ( X ) ) (i.e. the number of holes) can also grow linearly in the cardinality of X. Lastly, we give an example illustrating that the geometric conditions do not translate simply into conditions sufficient to completely characterize the Steiner reducing set.
Coordinating cardiomyocyte interactions to direct ventricular chamber morphogenesis

A complex interplay involving Notch- and Erbb2-mediated signalling between cardiomyocytes guides the morphogenesis of the ventricular wall.
Do Campus Police Ruin College Students’ Fun?

ABSTRACTCollege students drink alcohol to have fun, but this can lead to trouble with campus police. Based on qualitative data obtained via interviews with 73 students, this article draws on the ethnographic perspective to describe and explain their perceptions of whether campus police ruin college students’ fun. Findings are discussed with respect to prior research on the topic, as well as their broader relevance to utilitarianism, police legitimacy, and procedural justice.
REMOVING WELL-FIXED CEMENTLESS COMPONENTS: TIPS FOR THE TRADE

Indications for removal of well-fixed cementless femoral components include infection, improper femoral height/offset/anteversion, and fracture. More recently, removal of well-fixed but recalled femoral components that are associated with adverse local tissue reaction (ALTR) has created a new indication for this procedure. The goal in all cases is to preserve bone stock and soft-tissue attachments to the greatest extent possible during implant removal. The strategy for implant removal depends to a large extent on the type of implant to be removed. Implants with limited proximal fixation can often be removed from the top using narrow osteotomes. Implants with more extensive fixation typically require more extensive exposure. When performing an extended trochanteric osteotomy, plan for the bone flap length based on measurement from the tip of the greater trochanter. Instead of devascularising the lateral bone flap, be sure to preserve the quadriceps attachment to the bone flap, exposing the lateral femur only where the transverse and posterior osteotomies are planned. The anterior osteotomy can be performed using a dotted line of osteotomes trans-muscularly as described by Heinz Wagner. Placement of a prophylactic cerclage below the osteotomy is prudent. Most importantly, if the need for a transfemoral exposure is likely, it should be performed primarily so that the posterior capsule and short rotators can be preserved. There is no need to perform a full posterior exposure and then to secondarily perform a transfemoral exposure since the former is unnecessary if the latter is performed. Discrete, limited fixation of the lateral bone flap proximally and distally should be performed to prevent strangulation of the living bone flap during the refixation process. The transfemoral technique can be applied not only to removal of well-fixed devices but also for conversion from hip fusion and for Z-shortening of the femur during Crowe 4 reconstruction instead of using a transverse osteotomy and intercalary shortening.
Model-free control of nonlinear stochastic systems in discrete time

Consider the problem of developing a controller for general (nonlinear and stochastic) discrete-time systems, where the equations governing the system are unknown. This paper presents an approach based on estimating a controller without building or assuming a model for the system. Such an approach has potential advantages in, e.g., accommodating systems with time-varying dynamics. The controller is constructed through use of a function approximator (FA) such as a neural network or polynomial (no FA is used for the unmodeled system equations). This involves the estimation of the unknown parameters within the FA. However, since no functional form is being assumed for the system equations, the gradient of the loss function for use in standard optimization algorithms is not available. Therefore, this paper considers the use of a stochastic approximation algorithm that is based on a simultaneous perturbation gradient approximation, which requires only system measurements (not a system model). Related to this, a convergence result for stochastic approximation algorithms with time-varying objective functions is established. It is shown that this algorithm can greatly enhance the efficiency over more standard stochastic approximation algorithms based on finite-difference gradient approximations.
From a real chair to a negative chair

In the fall of 1977, I was invited by Raj Reddy to spend a year at the Computer Science Department of Carnegie Mellon University as a visiting scientist from Kyoto University in Japan. My plan for research during the stay was to develop a model-based object recognition program. Upon arrival, I chose an image of an office scene (Fig. 1 ) as an example image; the image was one of a set that Ron Ohlander had used in his research on color image segmentation. The task I set for my program was to recognize the chair in this image. I began to write a "knowledge-based" program for chair recognition by creating a set of heuristic rules for the task. It seemed that in addition to geometric relationships, a good source of constraints was color information, such as "the back and the seat of a chair have the same color". The effort of creating heuristic rules one after another, however, was not a satisfying game, since every time I came up with a reasonably functioning program, I could also find a chair that was an exception to the rules.
Determination of depth for electron breast boosts

A technique has been developed to determine the depth for the electron boost treatments for patients undergoing definitive irradiation for early stage breast cancer. A series of parallel link chains are placed on the breast over the clinically determined site of the boost. Using fluoroscopy, the physician confirms that the chains overlie the tumor bed which is outlined by radiopaque surgical clips placed at the time of the breast biopsy. A pair of orthogonal films and/or rotational stereo shift films are obtained with a standard simulator unit. Using the image of the chains to define the surface contour, the depth of each surgical clip is measured directly from the orthogonal films or calculated from the rotational stereo shift films. With this information, the physician can determine the appropriate electron energy to cover the target volume. This method was tested by comparison with depths measured from CT scan, and close agreement was demonstrated.
Single targeted exon mutation creates a true congenic mouse for competitive hematopoietic stem cell transplantation: the C57BL/6-CD45.1stem mouse

Defining the molecular regulators of hematopoietic stem and progenitor cells (HSPCs) requires in vivo functional analyses. Competitive bone marrow transplants (BMTs) compare control and test HSPCs to demonstrate the functional role of a genetic change or chemical perturbation. Competitive BMT is enabled by antibodies that specifically recognize hematopoietic cells from congenic mouse strains due to variants of the cell surface protein CD45, designated CD45.1 and CD45.2. The current congenic competitor strain, B6.SJL-Ptprc(a) Pepc(b)/BoyJ (CD45.1), has a substantial inherent disadvantage in competition against the C57BL/6 (CD45.2) strain, confounding experimental interpretation. Despite backcrossing, the congenic interval over which the B6.SJL-Ptprc(a) Pepc(b)/BoyJ strain differs is almost 40 Mb encoding ∼300 genes. Here, we demonstrate that a single amino acid change determines the CD45.1 epitope. Further, we report on the single targeted exon mutant (STEM) mouse strain, CD45.1(STEM), which is functionally equivalent to CD45.2 cells in competitive BMT. This strain will permit the precise definition of functional roles for candidate genes using in vivo HSPC assays.
A robust two‐stage design identifying the optimal biological dose for phase I/II clinical trials

We propose a robust two-stage design to identify the optimal biological dose for phase I/II clinical trials evaluating both toxicity and efficacy outcomes. In the first stage of dose finding, we use the Bayesian model averaging continual reassessment method to monitor the toxicity outcomes and adopt an isotonic regression method based on the efficacy outcomes to guide dose escalation. When the first stage ends, we use the Dirichlet-multinomial distribution to jointly model the toxicity and efficacy outcomes and pick the candidate doses based on a three-dimensional volume ratio. The selected candidate doses are then seamlessly advanced to the second stage for dose validation. Both toxicity and efficacy outcomes are continuously monitored so that any overly toxic and/or less efficacious dose can be dropped from the study as the trial continues. When the phase I/II trial ends, we select the optimal biological dose as the dose obtaining the minimal value of the volume ratio within the candidate set. An advantage of the proposed design is that it does not impose a monotonically increasing assumption on the shape of the dose-efficacy curve. We conduct extensive simulation studies to examine the operating characteristics of the proposed design. The simulation results show that the proposed design has desirable operating characteristics across different shapes of the underlying true dose-toxicity and dose-efficacy curves. The software to implement the proposed design is available upon request. Copyright © 2016 John Wiley & Sons, Ltd.
Putting down roots: a graphical exploration of community attachment

In this paper, we explore the relationships that individuals have with their communities. This work was prepared as part of the ASA Data Expo ‘13 sponsored by the Graphics Section and the Computing Section, using data provided by the Knight Foundation Soul of the Community survey. The Knight Foundation in cooperation with Gallup surveyed 43,000 people over 3 years in 26 communities across the United States with the intention of understanding the association between community attributes and the degree of attachment people feel towards their community. These include the different facets of both urban and rural communities, the impact of quality education, and the trend in the perceived economic conditions of a community over time. The goal of our work is to facilitate understanding of why people feel attachment to their communities through the use of an interactive and web-based visualization. We will explain the development and use of web-based interactive graphics, including an overview of the R package Shiny and the JavaScript library D3, focusing on the choices made in producing the visualizations and technical aspects of how they were created. Then we describe the stories about community attachment that unfolded from our analysis.
Percutaneous nephrolithotomy in the superobese: A comparison of outcomes based on body mass index

Abstract Introduction: Percutaneous nephrolithotomy (PCNL) is considered the gold standard for treatment of large renal calculi. Although several investigators have examined the feasibility and outcomes associated with PCNL in obese patients, these studies have been limited by small sample size, lack of a comparator group, or few patients at body mass index (BMI) extremes. We thus compared outcomes of superobese (BMI >50) patients undergoing PCNL vs both an “overweight” and “ideal” cohort. Methods: We used a prospectively maintained database to identify ideal (BMI 18.5–25), overweight (BMI 25.1–49.9), and superobese (BMI ≥50) patients who underwent PCNL. Our primary objective was to compare surgical outcomes between groups measured by the percent of patients who required secondary PCNL. We then compared complication rates, need for transfusion, and length of stay (LOS) using chi-square testing and ANOVA where appropriate. Results: A total of 1152 patients were identified of which 254 were classified as id...
Self-employment among women: Do children matter more than we previously thought?

Summary This paper presents an estimation approach that addresses the problems of sample selection and endogeneity of fertility decisions when estimating the effect of young children on women's self-employment. Using data from the National Longitudinal Survey of Youth 1979, 1982–2006, we find that ignoring self-selection and endogeneity leads to underestimating the effect of young children. Once both sources of biases are accounted for, the estimated effect of young children roughly triples when compared to uncorrected results. This finding is robust to several changes in the specification and to the use of a different dataset.
Locating and characterizing burials using 3D ground-penetrating radar (GPR) and terrestrial laser scanning (TLS) at the historic Mueschke Cemetery, Houston, Texas

Abstract We use ground-penetrating radar (GPR), terrestrial laser scanning (TLS), cemetery records, and oral histories to locate and characterize unmarked burials at the Mueschke Cemetery in Houston, Texas. We employ TLS surveying for the reconnaissance of the various types of burials in the cemetery. Concrete burials were used after 1940 while wooden burials were common before 1940. Strong correlations of TLS shallow surface mounds and depressions with known burials provide substantial motivation to follow-up with a detailed investigation with GPR. To calibrate the GPR survey, we undertook excavation and lab experiments to measure relative dielectric constant (3 − 10), moisture content (14%–21%), and electrical conductivity (0.36–0.38 S/m) of the location's soil. Grain-size experiments indicated that the soil at the survey location is reasonable for GPR, which was subsequently reinforced by the high quality GPR images with a depth of penetration of about 2.5 m and a vertical resolution of 6 cm. Numerical modeling provided a signature of a concrete burial with a flat rectangular top while a wooden burial resembles a typical hyperbola shape. 2D GPR template surveys over concrete and wooden burials show strong response and follow the numerical modeling findings. Three methods were used to estimate the soil radar velocity: CMP, two-way travel time (TWTT), and hyperbola fitting. These techniques yielded a soil velocity of about 0.055–0.067 m/ns. 3D GPR surveys produced anomalies that were consistent with headstones, cemetery records, and oral histories. Taking GPR depth slices overlain on the TLS elevation profile and cemetery records strongly indicated the location of two suspected unmarked graves including the oldest burial (1875) of James West.
Gender/Genre: The Lack of Gendered Register in Texts Requiring Genre Knowledge

Some studies have found characteristics of written texts that vary with author gender, echoing popular beliefs about essential gender differences that are reinforced in popular works of some schola...
Estimating Dynamic Discrete-Choice Games of Incomplete Information

We investigate the estimation of models of dynamic discrete-choice games of incomplete information, formulating the maximum-likelihood estimation exercise as a constrained optimization problem which can be solved using state-of-the-art constrained optimization solvers. Under the assumption that only one equilibrium is played in the data, our approach avoids repeatedly solving the dynamic game or nding all equilibria for each candidate vector of the structural parameters. We conduct Monte Carlo experiments to investigate the numerical performance and nite-sample properties of the constrained optimization approach for computing the maximum-likelihood estimator, the two-step pseudo maximum-likelihood estimator and the nested pseudo-likelihood estimator, implemented by both the nested pseudo-likelihood algorithm and a modied nested pseudo-likelihood algorithm.
The Complexity of Conversing About Entrepreneurship, Innovation, and Antitrust:

The relationship between law including competition policy and the goal of advancing innovation and entrepreneurship is complex. Bert Foer’s chapter identifies the many ways that competition law and policy directly and indirectly can affect positively or negatively the advancement of that goal. The comment seeks to highlight that range and complexity by using the categories from the traditional I-O Paradigm to show where and how antitrust law and policies it seeks to advance can be used to shape the conditions, structure, and conduct in markets to facilitate outcomes that will advance the public interest in innovation and entrepreneurship.
Simulation and assessment of ion kinetic effects in a direct-drive capsule implosion experiment

The first simulations employing a kinetic treatment of both fuel and shell ions to model inertial confinement fusion experiments are presented, including results showing the importance of kinetic physics processes in altering fusion burn. A pair of direct drive capsule implosions performed at the OMEGA facility with two different gas fills of deuterium, tritium, and helium-3 are analyzed. During implosion shock convergence, highly non-Maxwellian ion velocity distributions and separations in the density and temperature amongst the ion species are observed. Diffusion of fuel into the capsule shell is identified as a principal process that degrades fusion burn performance.
Utilization of Deep Reinforcement Learning for Saccadic-Based Object Visual Search

The paper focuses on the problem of learning saccades enabling visual object search. The developed system combines reinforcement learning with a neural network for learning to predict the possible outcomes of its actions. We validated the solution in three types of environment consisting of (pseudo)-randomly generated matrices of digits. The experimental verification is followed by the discussion regarding elements required by systems mimicking the fovea movement and possible further research directions.
The Effects of Income Mobility and Tax Persistence on Income Redistribution and Inequality

We explore the effect of income mobility and the persistence of redistributive tax policy on the level of redistribution in democratic societies. An infinite-horizon theoretical model is developed, and the properties of the equilibrium tax rate and the degree of after-tax inequality are characterized. Mobility and stickiness of tax policy are both negatively related to the equilibrium tax rate. However, neither is sufficient by itself. Social mobility has no effect on equilibrium taxes if tax policy is voted on in every period, and tax persistence has no effect in the absence of social mobility. The two forces are complementary. Tax persistence leads to higher levels of post-tax inequality, for any amount of mobility. The effect of mobility on inequality is less clear-cut and depends on the degree of tax persistence. A laboratory experiment is conducted to test the main comparative static predictions of the theory, and the results are generally supportive.
Connecting Seed Lists of Mammalian Proteins Using Steiner Trees

Multivariate experiments and genomics studies applied to mammalian cells often produce lists of genes or proteins altered under treatment/disease vs. control/normal conditions. Such lists can be identified in known protein-protein interaction networks to produce subnetworks that "connect" the genes or proteins from the lists. Such subnetworks are valuable for biologists since they can suggest regulatory mechanisms that are altered under different conditions. Often such subnetworks are overloaded with links and nodes resulting in connectivity diagrams that are illegible due to edge overlap. In this study, we attempt to address this problem by implementing an approximation to the Steiner tree problem to connect seed lists of mammalian proteins/genes using literature-based protein-protein interaction networks. To avoid over-representation of hubs in the resultant Steiner trees we assign a cost to Steiner vertices based on their connectivity degree. We applied the algorithm to lists of genes commonly mutated in colorectal cancer to demonstrate the usefulness of this approach.
An empirical analysis of video viewing behaviors in flipped CS1 courses

Video-enabled education is becoming increasingly popular in support of active learning in CS education. Although present work on both video based learning and flipped classrooms emphasize the necessity for students to view the materials, there is a lack of detailed, objective data on student viewing behaviors. This article aims to use fine grain student log data from TrACE, an asynchronous media platform, to understand student viewing behaviors in three sections of a flipped CS1 course taught by the same instructor. We find that students often have low compliance with video viewing expectations in one section, and that re-watching course content does not often occur. Watching course content earlier has a significant correlation to course performance, and other behaviours correlate when compliance is not enforced via course requirements. These findings highlight concerns for flipped classroom researchers and suggest methods instructors can use to improve student viewing behaviors.
Comparative study of visible light polymerized gelatin hydrogels for 3D culture of hepatic progenitor cells

Photopolymerization techniques have been widely used to create hydrogels for biomedical applications. Visible light-based photopolymerizations are commonly initiated by type II (i.e., noncleavage-type) photoinitiator in conjunction with a coinitiator. On the other hand, type I photoinitiators (i.e., cleavage type) are rarely compatible with visible light-based initiation due to their limited molar absorbability in the visible light wavelengths. Here, we report visible light initiated orthogonal photoclick crosslinking to fabricate gelatin-norbornene and poly(ethylene glycol)-tetra-thiol hydrogels using either cleavage-type (i.e., lithium acylphosphinate, LAP) or noncleavage-type photoinitiator (i.e., eosin-Y, EY) without the use of a coinitiator. Regardless of the initiator type, the step-growth gelatin-PEG hybrid hydrogels crosslinked and degraded similarly. While both systems exhibited similar cytocompatibility for hepatic progenitor HepaRG cells, gelation initiated by noncleavage-type initiator EY afforded slightly higher degree of hepatic gene expression. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44585.
SPECtre: a spectral coherence-­based classifier of actively translated transcripts from ribosome profiling sequence data

Active protein translation can be assessed and measured using ribosome profiling sequencing strategies. Prevailing analytical approaches applied to this technology make use of sequence fragment length profiling or reading frame occupancy enrichment to differentiate between active translation and background noise, however they do not consider additional characteristics inherent to the technology which limits their overall accuracy. Here, we present an analytical tool that models the overall tri­nucleotide periodicity of ribosomal occupancy using a classifier based on spectral coherence. Our software, SPECtre, examines the relationship of normalized ribosome profiling read coverage over a rolling series of windows along a transcript relative to an idealized reference signal without the matched requirement of mRNA-Seq. A comparison of SPECtre against previously published methods on existing data shows a marked improvement in accuracy for detecting active translation and exhibits overall high accuracy at a low false discovery rate. In addition, SPECtre performs comparably to a recently published method similarly based on spectral coherence, however with reduced runtime and memory requirements. SPECtre is available as an open source software package at https://github.com/mills-lab/spectre .
Middlemen: the good, the bad, and the ugly

We examine the role of a middleman as an expert in markets. A seller's effort determines the quality of the good. Buyers observe neither the seller's effort nor the good's quality. A middleman, after observing a signal about the good's quality, decides whether to purchase it and then to sell it. We show that the presence of a middleman may either reduce or exacerbate the seller's moral hazard problem. We also consider a model with multiple middlemen. We find that the seller's effort is minimized if either the middleman's signal is perfect or the number of middlemen is large.
Multi-level 3-D rotational invariant classification

A two-level 3D rotational invariant classification is developed based on fractional differencing model. In first level, classification has been done with a fractal scale, and in second level, textures have been classified further in detail with the additional frequency parameters. Because of the properties of the fractal scale and multi-level procedure, the proposed 3D rotational invariant classification scheme reduces the processing time and gives enough accuracy of the classification simultaneously. As a result of a series of experiments involving the differently oriented samples of natural textures, it is concluded that these combined features make possible for this multi-level classification method to have a strong class separability power for arbitrary oriented 3D texture patterns. >
An Effective Method for Evaluating the Accuracy of Power Hardware-in-the-Loop Simulations

Power hardware-in-the-loop (PHIL) simulations need to be accurate to truly reflect the behavior of the systems under test. However, a PHIL simulation may result in errors or even instability due to imperfections (e.g., time delay, noise injection, phase lag, and limited bandwidth) in the power interface, particularly in high-power applications. Additionally, it is usually difficult to determine the accuracy of a simulation because there is no reference available for people to know the ldquoshould-berdquo system responses in advance. Therefore, a method is demanded to predict the accuracy of PHIL simulations. In this paper, an effective method for evaluating the PHIL accuracy is proposed. This method provides a means to justify the result of a PHIL simulation analytically and quantitatively instead of empirically. While the method is based on linear system analysis, it is shown to be also applicable for nonlinear PHIL systems.
Is cost–benefit analysis a foreign language?:

Do people think better in a foreign language? In some ways, yes. There is considerable evidence to this effect, at least to the extent that they are less likely to rely on intuitions that can lead to serious errors. This finding reinforces, and makes more plausible, a central claim in regulatory policy, which involves the value of cost-benefit analysis. In a sense, cost-benefit analysis is a foreign language, and it reduces the risk that people will rely on intuitions that cause serious errors.
Overview of SIM external calibration

Like all astrometric instruments, the Space Interferometry Mission (SIM) suffers from field-dependent errors requiring calibration. Diffraction effects in the delay line, polarization rotations on corner cubes, and beam walk across imperfect optics, all contribute to field-distortion that is significantly larger than is acceptable. The bulk of the systematic error is linear across the field - that is, it results in magnification and rotation errors. We show that the linear terms are inconsequential to the performance of SIM because they are inseparable from baseline length and orientation errors. One approach to calibrating the higher-order terms is to perform 'external' calibration; that is, SIM periodically makes differential measurements of a field of bright stars whose positions are not precisely known. We describe the requirements and constraints on the external calibration process and lay the groundwork for a specific procedure detailed in accompanying papers.
Identifying nonlinear 1-step causal influences in presence of latent variables

We propose an approach for learning the causal structure in stochastic dynamical systems with a 1-step functional dependency in the presence of latent variables. We propose an information-theoretic approach that allows us to recover the causal relations among the observed variables as long as the latent variables evolve without exogenous noise. We further propose an efficient learning method based on linear regression for the special sub-case when the dynamics are restricted to be linear. We validate the performance of our approach via numerical simulations.
PARAID: a gear-shifting power-aware RAID

Reducing power consumption for server computers is important, since increased energy usage causes increased heat dissipation, greater cooling requirements, reduced computational density, and higher operating costs. For a typical data center, storage accounts for 27% of energy consumption. Conventional server-class RAIDs cannot easily reduce power because loads are balanced to use all disks even for light loads. We have built the Power-Aware RAID (PARAID), which reduces energy use of commodity server-class disks without specialized hardware. PARAID uses a skewed striping pattern to adapt to the system load by varying the number of powered disks. By spinning disks down during light loads, PARAID can reduce power consumption, while still meeting performance demands, by matching the number of powered disks to the system load. Reliability is achieved by limiting disk power cycles and using different RAID encoding schemes. Based on our five-disk prototype, PARAID uses up to 34% less power than conventional RAIDs, while achieving similar performance and reliability.
The impact of antenatal testing for advanced maternal age on cesarean delivery rate at an urban institution

The birth rate for women over the age of 40 continues to increase with a rate of 11 births per 1,000 women in 2011.1 Advanced maternal age (AMA) has been associated with an increased riskof stillbirth2–5 even after controlling for risk factors such as hypertension, diabetes, and multiple gestation.2,3 While Fretts et al found an increase in the stillbirth rate among women older than 35 years of age, this rate was significantly higher in women over the age of 40.3 A 2.4-fold increased rate of stillbirth among women 40 years old or greater was noted when compared with women less than 40 years old.3 While the risk of stillbirth increases after 38 weeks for all age groups, Reddy et al noted that it was most remarkable in women over the age of 40, with a hazard of death of 2.5 per 1,000 for ongoing pregnancies in this age category.2 Given the known association of AMA and stillbirth, with a greater risk noted after the age of 40, antenatal testing guidelines have been implemented at many institutions based on maternal age greater than 40 years old. It is plausible that antenatal testing may lead to a higher rate of medical intervention including a higher rate of induction of labor and cesarean delivery. While a higher induction and cesarean delivery rate may be acceptable when the intervention is thought to prevent stillbirths, it is important to understand the implications that antenatal testing has in the AMA population to better counsel our patients. The objective of this study was to evaluate the rate of cesarean delivery and induction of labor among women of AMA who had antenatal testing for AMA compared with those who delivered before the implementation of antenatal testing for AMA. Our hypothesis was that women who undergo antenatal testing for AMA have higher cesarean delivery and induction rates.
Price dispersion in stationary networked markets

Abstract Different sellers often sell the same good at different prices. Using a strategic bargaining model, I characterize how the equilibrium prices of a good depend on the interaction between its sellers' costs, its buyers' values, and a network capturing various frictions associated with trading it. In contrast to the standard random-matching model of bargaining in stationary markets, I allow agents to strategically choose whom to make offers to, which qualitatively changes how the network shapes prices. As in the random-matching model, the market decomposes into different submarkets, and—in the limit as bargaining frictions vanish—the law of one price holds within but not across them. But strategic choice of partners changes both how the market decomposes into different submarkets and the determinants of each submarket's price.
Superconcentration, and randomized Dvoretzky's theorem for spaces with 1-unconditional bases

Abstract Let n be a sufficiently large natural number and let B be an origin-symmetric convex body in R n in the l-position, and such that the space ( R n , ‖ ⋅ ‖ B ) admits a 1-unconditional basis. Then for any e ∈ ( 0 , 1 / 2 ] , and for random c e log ⁡ n / log ⁡ 1 e -dimensional subspace E distributed according to the rotation-invariant (Haar) measure, the section B ∩ E is ( 1 + e ) -Euclidean with probability close to one. This shows that the “worst-case” dependence on e in the randomized Dvoretzky theorem in the l-position is significantly better than in John's position. It is a previously unexplored feature, which has strong connections with the concept of superconcentration introduced by S. Chatterjee. In fact, our main result follows from the next theorem: Let B be as before and assume additionally that B has a smooth boundary and E γ n ‖ ⋅ ‖ B ≤ n c E γ n ‖ grad B ( ⋅ ) ‖ 2 for a small universal constant c > 0 , where grad B ( ⋅ ) is the gradient of ‖ ⋅ ‖ B and γ n is the standard Gaussian measure in R n . Then for any p ∈ [ 1 , c log ⁡ n ] the p-th power of the norm ‖ ⋅ ‖ B p is C log ⁡ n -superconcentrated in the Gauss space.
Resilient monotone submodular function maximization

In this paper, we focus on applications in machine learning, optimization, and control that call for the resilient selection of a few elements, e.g. features, sensors, or leaders, against a number of adversarial denial-of-service attacks or failures. In general, such resilient optimization problems are hard, and cannot be solved exactly in polynomial time, even though they often involve objective functions that are monotone and submodular. Notwithstanding, in this paper we provide the first scalable algorithm for their approximate solution, that is valid for any number of attacks or failures, and which, for functions with low curvature, guarantees superior approximation performance. Notably, the curvature has been known to tighten approximations for several non-resilient maximization problems, yet its effect on resilient maximization had hitherto been unknown. We complement our theoretical analyses with supporting empirical evaluations.
Open set intrusion recognition for fine-grained attack categorization

Confidently distinguishing a malicious intrusion over a network is an important challenge. Most intrusion detection system evaluations have been performed in a closed set protocol in which only classes seen during training are considered during classification. Thus far, there has been no realistic application in which novel types of behaviors unseen at training - unknown classes as it were - must be recognized for manual categorization. This paper comparatively evaluates malware classification using both closed set and open set protocols for intrusion recognition on the KDDCUP'99 dataset. In contrast to much of the previous work, we employ a fine-grained recognition protocol, in which the dataset is loosely open set - i.e., recognizing individual intrusion types - e.g., “sendmail”, “snmp_guess”, …, etc., rather than more general attack categories (e.g., “DoS”,“Probe”,“R2L”,“U2R”,“Normal”). We also employ two different classifier types - Gaussian RBF kernel SVMs, which are not theoretically guaranteed to bound open space risk, and W-SVMs, which are theoretically guaranteed to bound open space risk. We find that the W-SVM offers superior performance under the open set regime, particularly as the cost of misclassifying unknown classes at query time (i.e., classes not present in the training set) increases. Results of performance tradeoff with respect to cost of unknown as well as discussion of the ramifications of these findings in an operational setting are presented.
Linear Additive Markov Processes

We introduce LAMP: the Linear Additive Markov Process. Transitions in LAMP may be influenced by states visited in the distant history of the process, but unlike higher-order Markov processes, LAMP retains an efficient parameterization. LAMP also allows the specific dependence on history to be learned efficiently from data. We characterize some theoretical properties of LAMP, including its steady-state and mixing time. We then give an algorithm based on alternating minimization to learn LAMP models from data. Finally, we perform a series of real-world experiments to show that LAMP is more powerful than first-order Markov processes, and even holds its own against deep sequential models (LSTMs) with a negligible increase in parameter complexity.
Discriminative Bimodal Networks for Visual Localization and Detection with Natural Language Queries

Associating image regions with text queries has been recently explored as a new way to bridge visual and linguistic representations. A few pioneering approaches have been proposed based on recurrent neural language models trained generatively (e.g., generating captions), but achieving somewhat limited localization accuracy. To better address natural-language-based visual entity localization, we propose a discriminative approach. We formulate a discriminative bimodal neural network (DBNet), which can be trained by a classifier with extensive use of negative samples. Our training objective encourages better localization on single images, incorporates text phrases in a broad range, and properly pairs image regions with text phrases into positive and negative examples. Experiments on the Visual Genome dataset demonstrate the proposed DBNet significantly outperforms previous state-of-the-art methods both for localization on single images and for detection on multiple images. We we also establish an evaluation protocol for natural-language visual detection. Code is available at: http://ytzhang.net/projects/dbnet.