cssi/SciSciGPT-SciSciNet huggingface dataset:
Error modeling for surrogates of dynamical systems using machine learning

Summary A machine-learning-based framework for modeling the error introduced by surrogate models of parameterized dynamical systems is proposed. The framework entails the use of high-dimensional regression techniques (e.g., random forests, LASSO) to map a large set of inexpensively computed ‘error indicators’ (i.e., features) produced by the surrogate model at a given time instance to a prediction of the surrogate-model error in a quantity of interest (QoI). This eliminates the need for the user to hand-select a small number of informative features. The methodology requires a training set of parameter instances at which the time-dependent surrogate-model error is computed by simulating both the high-fidelity and surrogate models. Using these training data, the method first determines regression-model locality (via classification or clustering), and subsequently constructs a ‘local’ regression model to predict the time-instantaneous error within each identified region of feature space. We consider two uses for the resulting error model: (1) as a correction to the surrogate-model QoI prediction at each time instance, and (2) as a way to statistically model arbitrary functions of the time-dependent surrogate-model error (e.g., time-integrated errors). We apply the proposed framework to model errors in reduced-order models of nonlinear oil–water subsurface flow simulations, with time-varying well-control (bottom-hole pressure) parameters. The reduced-order models used in this work entail application of trajectory piecewise linearization in conjunction with proper orthogonal decomposition. When the first use of the method is considered, numerical experiments demonstrate consistent improvement in accuracy in the time-instantaneous QoI prediction relative to the original surrogate model, across a large number of test cases. When the second use is considered, results show that the proposed method provides accurate statistical predictions of the time- and well-averaged errors. This article is protected by copyright. All rights reserved.
Expected Number of Critical Points of Random Holomorphic Sections Over Complex Projective Space

We study the high-dimensional asymptotics of the expected number of critical points of a given Morse index of Gaussian random holomorphic sections over complex projective space. We explicitly compute the exponential growth rate of the expected number of critical points of the largest index and of diverging indices at various rates as well as the exponential growth rate for the expected number of critical points (regardless of index). We also compute the distribution of the critical values for the expected number of critical points of smallest index.
Accurate calculation of the geometric measure of entanglement for multipartite quantum states

This article proposes an efficient way of calculating the geometric measure of entanglement using tensor decomposition methods. The connection between these two concepts is explored using the tensor representation of the wavefunction. Numerical examples are benchmarked and compared. Furthermore, we search for highly entangled qubit states to show the applicability of this method.
Dirac-electron-mediated magnetic proximity effect in topological insulator/magnetic insulator heterostructures

The possible realization of dissipationless chiral edge current in a topological insulator/magnetic insulator heterostructure is based on the condition that the magnetic proximity exchange coupling at the interface is dominated by the Dirac surface states of the topological insulator. Here we report a polarized neutron reflectometry observation of Dirac-electron-mediated magnetic proximity effect in a bulk-insulating topological insulator $(\mathrm{B}{\mathrm{i}}_{0.2}\mathrm{S}{\mathrm{b}}_{0.8}{)}_{2}\mathrm{T}{\mathrm{e}}_{3}$/magnetic insulator EuS heterostructure. We are able to maximize the proximity-induced magnetism by applying an electrical back gate to tune the Fermi level of topological insulator to be close to the Dirac point. A phenomenological model based on diamagnetic screening is developed to explain the suppressed proximity-induced magnetism at high carrier density. Our work paves the way to utilize the magnetic proximity effect at the topological insulator/magnetic insulator heterointerface for low-power spintronic applications.
INTERNAL KINEMATICS OF THE ANDROMEDA II DWARF SPHEROIDAL GALAXY

The High-Resolution Echelle Spectrometer on the Keck I telescope has been used to measure nine radial velocities having a median precision of ^ 2k m s~1 for seven red giants belonging to the isolated dwarf spheroidal galaxy Andromeda II (And II). We —nd a weighted mean radial velocity of v r \( 188 ^ 3k m s~1 and a central velocity dispersion of km s~1. There may be evidence for a p 0 \ 9.3 ~2.62.7 radial velocity gradient across the face of the galaxy, although the signi—cance of this result is low because of the small number of stars having measured velocities. Our best estimate for the global mass- to-light ratio of And II is This value is similar to those of several Galactic M/L V \ 20.9 ~10.113.9 M _ /L V,_ . dwarf spheroidal galaxies and is consistent with the presence of a massive dark halo in And II. Subject headings: galaxies: dwarfgalaxies: individual (Andromeda II) ¨ galaxies: kinematics and dynamics
Impairment of early fracture healing by skeletal muscle trauma is restored by FK506

Heightened local inflammation due to muscle trauma or disease is associated with impaired bone regeneration. We hypothesized that FK506, an FDA approved immunomodulatory compound with neurotrophic and osteogenic effects, will rescue the early phase of fracture healing which is impaired by concomitant muscle trauma in male (~4 months old) Lewis rats. FK506 (1 mg/kg; i.p.) or saline was administered systemically for 14 days after an endogenously healing tibia osteotomy was created and fixed with an intermedullary pin, and the overlying tibialis anterior (TA) muscle was either left uninjured or incurred volumetric muscle loss injury (6 mm full thickness biopsy from middle third of the muscle). The salient observations of this study were that 1) concomitant TA muscle trauma impaired recovery of tibia mechanical properties 28 days post-injury, 2) FK506 administration rescued the recovery of tibia mechanical properties in the presence of concomitant TA muscle trauma but did not augment mechanical recovery of an isolated osteotomy (no muscle trauma), 3) T lymphocytes and macrophage presence within the traumatized musculature were heightened by trauma and attenuated by FK506 3 days post-injury, and 4) T lymphocyte but not macrophage presence within the fracture callus were attenuated by FK506 at 14 days post-injury. FK506 did not improve TA muscle isometric torque production Collectively, these findings support the administration of FK506 to ameliorate healing of fractures with severe muscle trauma comorbidity. The results suggest one potential mechanism of action is a reduction in local T lymphocytes within the injured musculoskeletal tissue, though other mechanisms to include direct osteogenic effects of FK506 require further investigation.
Decoy peptide targeted to Toll-IL-1R domain inhibits LPS and TLR4-active metabolite morphine-3 glucuronide sensitization of sensory neurons

Accumulating evidence indicates that Toll-like receptor (TLR) signaling adapter protein interactions with Toll/Interleukin-1 Receptor (TIR) domains present in sensory neurons may modulate neuropathic pain states. Following ligand interaction with TLRs, TIR serves to both initiate intracellular signaling and facilitate recruitment of signaling adapter proteins to the intracytoplasmic domain. Although TLR TIR is central to a number of TLR signaling cascades, its role in sensory neurons is poorly understood. In this study we investigated the degree to which TLR TIR decoy peptide modified to include a TAT sequence (Trans-Activator of Transcription gene in HIV; TAT-4BB) affected LPS-induced intracellular calcium flux and excitation in sensory neurons, and behavioral changes due to TLR4 active metabolite, morphine-3-glucuronide (M3G) exposure in vivo. TAT-4BB inhibited LPS-induced calcium changes in a majority of sensory neurons and decreased LPS-dependent neuronal excitability in small diameter neurons. Acute systemic administration of the TAT-4BB reversed M3G-induced tactile allodynia in a dose-dependent manner but did not affect motor activity, anxiety or responses to noxious thermal stimulus. These data suggest that targeting TLR TIR domains may provide novel pharmacological targets to reduce or reverse TLR4-dependent pain behavior in the rodent.
Predicting DNA hybridization kinetics from sequence

The rate constant of DNA hybridization varies over several orders of magnitude and is affected by temperature and DNA sequence. A machine-learning algorithm that is capable of accurately predicting hybridization rate constants has now been developed. Tests with this algorithm showed that over 90% of predictions were correct to within a factor of three.
Nonseparable multinomial choice models in cross-section and panel data

Abstract Multinomial choice models are fundamental for empirical modeling of economic choices among discrete alternatives. We analyze identification of binary and multinomial choice models when the choice utilities are nonseparable in observed attributes and multidimensional unobserved heterogeneity with cross-section and panel data. We show that derivatives of choice probabilities with respect to continuous attributes are weighted averages of utility derivatives in cross-section models with exogenous heterogeneity. In the special case of random coefficient models with an independent additive effect, we further characterize that the probability derivative at zero is proportional to the population mean of the coefficients. We extend the identification results to models with endogenous heterogeneity using either a control function or panel data. In time stationary panel models with two periods, we find that differences over time of derivatives of choice probabilities identify utility derivatives “on the diagonal,” i.e. when the observed attributes take the same values in the two periods. We also show that time stationarity does not identify structural derivatives “off the diagonal” both in continuous and multinomial choice panel models.
Macroprudential policy and the revolving door of risk: Lessons from leveraged lending guidance

Abstract We investigate the U.S. experience with macroprudential policies by studying the interagency guidance on leveraged lending. We find that the guidance primarily impacted large, closely supervised banks, but only after supervisors issued important clarifications. It also triggered a migration of leveraged lending to nonbanks. While we do not find that nonbanks use more lax lending policies than banks, we unveil important evidence that nonbanks increased bank borrowing following the guidance, possibly to finance their growing leveraged lending. The guidance was effective at reducing banks’ leveraged lending activity, but it is less clear whether it accomplished its broader goal of reducing the risk that these loans pose for the stability of the financial system. Our findings highlight the importance of supervisory monitoring for macroprudential policy goals, and the challenge that the revolving door of risk poses to the effectiveness of macroprudential regulations.
A generative model of group conversation

Conversations with non-player characters (NPCs) in games are typically confined to dialogue between a human player and a virtual agent, where the conversation is initiated and controlled by the player. To create richer, more believable environments for players, we need conversational behavior to reflect initiative on the part of the NPCs, including conversations that include multiple NPCs who interact with one another as well as the player. We describe a generative computational model of group conversation between agents, an abstract simulation of discussion in a small group setting. We define conversational interactions in terms of rules for turn taking and interruption, as well as belief change, sentiment change, and emotional response, all of which are dependent on agent personality, context, and relationships. We evaluate our model using a parameterized expressive range analysis, observing correlations between simulation parameters and features of the resulting conversations. This analysis confirms, for example, that character personalities will predict how often they speak, and that heterogeneous groups of characters will generate more belief change.
Scientific workflows at DataWarp-speed: Accelerated data-intensive science using Nersc's burst buffer

© 2016 IEEE.Emerging exascale systems have the ability to accelerate the time-to-discovery for scientific workflows. However, as these workflows become more complex, their generated data has grown at an unprecedented rate, making I/O constraints challenging. To address this problem advanced memory hierarchies, such as burst buffers, have been proposed as intermediate layers between the compute nodes and the parallel file system. In this paper, we utilize Cray DataWarp burst buffer coupled with in-transit processing mechanisms, to demonstrate the advantages of advanced memory hierarchies in preserving traditional coupled scientific workflows. We consider in-transit workflow which couples simulation of subsurface flows with on-the-fly flow visualization. With respect to the proposed workflow, we study the performance of the Cray DataWarp Burst Buffer and provide a comparison with the Lustre parallel file system.
Security on the US fusion grid

Abstract The National Fusion Collaboratory project is developing and deploying new distributed computing and remote collaboration technologies with the goal of advancing magnetic fusion energy research. This has led to the development of the U.S. fusion grid (FusionGrid), a computational grid composed of collaborative, compute, and data resources from the three large U.S. fusion research facilities and with users both in the U.S. and in Europe. Critical to the development of FusionGrid was the creation and deployment of technologies to ensure security in a heterogeneous environment. These solutions to the problems of authentication, authorization, data transfer, and secure data storage, as well as the lessons learned during the development of these solutions, may be applied outside of FusionGrid and scale to future computing infrastructures such as those for next-generation devices like ITER.
Effects of low-salinity waterflooding on capillary pressure hysteresis

Abstract In this study, low-salinity waterflooding enhanced-oil recovery mechanisms linked to the water–crude oil interfacial viscoelastic response are investigated considering a distinct interfacial effect, namely the water-crude oil interfacial viscoelasticity response. In contrast, wettability alteration is interpreted through analysis of capillary hysteresis. A capillary pressure experimental setup used in our previous research, is utilized here to capture capillary hysteresis. Moreover, new improvements over the traditional quasi-static porous plate method have been implemented to accelerate measurements. The dynamic-static method, i.e. a combination of continuous injection in drainage and stepwise quasi-static method in imbibition on short ( 1 ″ long) core samples, was found to capture the correct envelopes of the capillary pressure curves in a much shorter time span. Two pairs of experiments were conducted to investigate the interfacial visco-elasticity and wettability alteration effects on capillary hysteresis. One pair is conducted on Minnelusa formation rock samples and diluted TC crude oil at 30 °C and without any significant aging to minimize wettability alteration. Two core plugs were flooded with high-salinity and low-salinity brines, separately. Results show that low-salinity brine can still increase oil recovery even in the absence of wettability alteration. This is attributed to the formation of a more visco-elastic brine-crude oil interface upon exposure to low-salinity brine, leading to a more continuous oil phase. Two additional experiment pairs were conducted on Berea and TC oil at high temperature (70 °C). Two cores were subject to the same experimental conditions except that one was allowed to age with crude oil for 3 weeks. This aging process was found to render the rock more oil wet, resulting in more pronounced capillary hysteresis and less oil recovery. Our study shows effects of two mechanisms, i.e. fluid–fluid interfacial visco-elasticity and wettability alteration, separately. The interpretation of our unique capillary pressure datasets sheds light on low-salinity waterflooding mechanisms.
Lymphography, a New Technique of Incision

An improved technique for exposing a lymph vessel prior to cannulation is introduced. This involves one clean incision and minimal dissection. Utilizing this technique, a vessel can be exposed within a minute. Damage to the skin and subcutaneous tissue is minimal. Leaking and procedure failures are rare. Fast healing occurs due to minimal incision length and trauma.
Percutaneous Nephrostomy in Gynecologic Oncology Patients

Percutaneous nephrostomies were used in 34 patients with ureteral obstruction caused by gynecologic diseases. Group 1 consisted of 12 patients with untreated cervical carcinoma; group 2 consisted of six patients with recurrent cervical carcinoma; group 3 consisted of seven patients with complications of urinary conduits, and group 4 consisted of eight patients with a variety of malignant and benign gynecologic diseases causing ureteral obstruction. One perinephric hematoma and one perinephric abscess (4%) occurred during primary percutaneous nephrostomy diversion of 53 renal units. One (3%) percutaneous nephrostomy-related death caused by sepsis was observed in 34 patients. Only four (12%) patients with significant intrinsic renal disease did not have effective normalization of renal function by percutaneous nephrostomy. Percutaneous nephrostomies allow rapid and reliable urinary diversion without the morbidity and mortality of operative techniques. Percutaneous nephrostomy should be considered for relief of ureteral obstruction in patients with untreated cervical carcinoma who may enjoy prolonged palliation or cure, in patients with complications of previous urinary conduits as a temporizing method of urinary diversion, and in patients with benign or chemotherapy-sensitive pelvic malignancies causing ureteral obstruction. The use of percutaneous nephrostomy in patients with recurrent carcinoma of the cervix should be individualized on the basis of expectations for prolonged functional palliation.
Mineral Dusts as Etiologic Agents in Pulmonary Fibrosis: The Diagnostic Role of Analytical Scanning Electron Microscopy

This report demonstrates the value of analytical scanning electron microscopy (SEM) in the evaluation of patients with fibrosing pulmonary disease. We describe the findings in six illustrative cases in which prebiopsy or premortem clinical and epidemiologic information did not suggest an etiologic association with exposure to fibrogenic dusts. Exogenous materials were inconstantly recognized by polarized light microscopy, but examination by SEM resulted in localization of significant inorganic deposits in the biopsy and autopsy tissues studied. Talc, mica, graphite, and mixed inorganic dusts were found in these six cases. Characterization of this material by SEM morphology and x-ray energy spectrometry provided the basis for re-appraisal of the exposure history and its potential pathogenetic importance. The technics described utilize routinely processed, paraffin-embedded tissue, and are readily applicable to problems encountered in the hospital setting.
Aid econometrics: Lessons from a stochastic growth model

Abstract This paper evaluates the standard empirical methods employed in the study of foreign aid, when the data generating process is a calibrated stochastic growth model in which aid recipients make optimal investment and consumption decisions. When recipients receive a stochastic flow of aid and wish to smooth consumption, standard methods fail to distinguish between the response to transient and permanent aid shocks, and hence yield misleading results concerning the object of interest to policy makers: the long-run impact of aid.
Evaluation of an objective assessment technique for the detection of malingered memory deficits

Clinicians generally operate under the implicit assumption that their clients are being honest and putting forth their best effort on assessment procedures. However, clients may realize substantial secondary gains by appearing impaired. The present study evaluates an objective assessment procedure for the detection of malingered memory deficits. Results demonstrate that college students instructed to malinger memory impairment show different patterns of responding and can be clearly differentiated from students performing their best and from actual memory-impaired patients. Applying one of two scores derived from this test to a sample of 20 students instructed to malinger, 20 control subjects, and 20 memory impaired subjects performing their best resulted in a 100% hit rate for normal controls and memory-impaired subjects, and a 65% hit rate for experimental malingerers.
Suppression and facilitation of human neural responses

Efficient neural processing depends on regulating responses through suppression and facilitation of neural activity. Utilizing a well-known visual motion paradigm that evokes behavioral suppression and facilitation, and combining five different methodologies (behavioral psychophysics, computational modeling, functional MRI, pharmacology, and magnetic resonance spectroscopy), we provide evidence that challenges commonly held assumptions about the neural processes underlying suppression and facilitation. We show that: (1) both suppression and facilitation can emerge from a single, computational principle - divisive normalization; there is no need to invoke separate neural mechanisms, (2) neural suppression and facilitation in the motion-selective area MT mirror perception, but strong suppression also occurs in earlier visual areas, and (3) suppression is not primarily driven by GABA-mediated inhibition. Thus, while commonly used spatial suppression paradigms may provide insight into neural response magnitudes in visual areas, they should not be used to infer neural inhibition.
Embracing a new era of highly efficient and productive quantum Monte Carlo simulations

QMCPACK has enabled cutting-edge materials research on supercomputers for over a decade. It scales nearly ideally but has low single-node efficiency due to the physics-based abstractions using array-of-structures objects, causing inefficient vectorization. We present a systematic approach to transform QMCPACK to better exploit the new hardware features of modern CPUs in portable and maintainable ways. We develop miniapps for fast prototyping and optimizations. We implement new containers in structure-of-arrays data layout to facilitate vectorizations by the compilers. Further speedup and smaller memory-footprints are obtained by computing data on the fly with the vectorized routines and expanding single-precision use. All these are seamlessly incorporated in production QMCPACK. We demonstrate upto 4.5x speedups on recent Intel® processors and IBM Blue Gene/Q for representative workloads. Energy consumption is reduced significantly commensurate to the speedup factor. Memory-footprints are reduced by up-to 3.8x, opening the possibility to solve much larger problems of future.
FEMORAL NECK FRACTURES: FIX OR REPLACE?

Few will disagree that the best femoral head that a young patient can have is his or her own, native femoral head. In the active, healthy patient under age 60 with a displaced femoral neck fracture, well-done, timely ORIF presents the best chance of preserving the patient9s native femoral head. Arthroplasty is generally reserved for older patients, over age 60, where attempts at ORIF in this setting have demonstrated failure rates over 40%. “Physiologic age” is a somewhat nebulous term that takes into account the health and ambulatory status of the patient. For example, a 52-year-old with end stage renal failure, severe osteoporosis, and a displaced femoral neck fracture may best be treated with arthroplasty. However, in reality, such situations are quite rare. Recent studies have documented that approximately 80% of young patients with displaced femoral neck fractures treated with ORIF will keep their own femoral head for 10 years after injury. The variables under the surgeon9s control include timing of fixation, quality of reduction, accurate implant placement and implant selection, and capsulotomy. All of these variables potentially affect outcomes. Fractures in this young age group are frequently high shear angle (vertical) Pauwels Type 3 fractures, and benefit from fixed angle fixation. The author prefers anatomic reduction and stabilisation with a sliding hip screw and a superiorly placed derotation screw. Careful attention to detail is important to obtain an anatomic reduction, which is the most important variable in the outcome of these challenging injuries.
Reduced Levels of mGlu2 Receptors within the Prelimbic Cortex Are Not Associated with Elevated Glutamate Transmission or High Alcohol Drinking

Background A Grm2 cys407* stop codon mutation, which results in a loss of the metabotropic glutamate 2 (mGlu2) receptor protein, was identified as being associated with high alcohol drinking by alcohol-preferring (P) rats. The objectives of the current study were to characterize the effects of reduced levels of mGlu2 receptors on glutamate transmission and alcohol drinking. Methods Quantitative no-net-flux microdialysis was used to test the hypothesis that basal extracellular glutamate levels in the prelimbic (PL) cortex and nucleus accumbens shell (NACsh) will be higher in P than Wistar rats. A lentiviral-delivered short-hairpin RNA (shRNA)-mediated knockdown was used to test the hypothesis that reduced levels of mGlu2 receptors within the PL cortex will increase voluntary alcohol drinking by Wistar rats. A linear regression analysis was used to test the hypothesis that there will be a significant correlation between the Grm2 cys407* mutation and level of alcohol intake. Results Extracellular glutamate concentrations within the PL cortex (3.6 ± 0.6 vs. 6.4 ± 0.6 μM) and NACsh (3.2 ± 0.4 vs. 6.6 ± 0.6 μM) were significantly lower in female P than female Wistar rats. Western blot detected the presence of mGlu2 receptors in these regions of female Wistar rats, but not female P rats. Micro-infusion of shRNAs into the PL cortex significantly reduced local mGlu2 receptor levels (by 40%), but did not alter voluntary alcohol drinking in male Wistar rats. In addition, there was no significant correlation between the Grm2 mutation and alcohol intake in 36 rodent lines (r = 0.29, p > 0.05). Conclusions Collectively, these results suggest a lack of association between the loss of mGlu2 receptors and glutamate transmission in the NACsh and PL cortex of female P rats, and between the level of mGlu2 receptors in the PL cortex and alcohol drinking of male Wistar rats.
California heat waves: their spatial evolution, variation, and coastal modulation by low clouds

We examine the spatial and temporal evolution of heat waves through California and consider one of the key modulating factors of summertime coastal climate—coastal low cloudiness (CLC). Heat waves are defined relative to daytime maximum temperature (Tmax) anomalies after removing local seasonality and capture unseasonably warm events during May—September. California is home to several diverse climate regions and characteristics of extreme heat events are also variable throughout these regions. Heat wave events tend to be shorter, but more anomalously intense along the coast. Heat waves typically impact both coastal and inland regions, although there is more propensity towards coastally trapped events. Most heat waves with a strong impact across regions start at the coast, proceed inland, and weaken at the coast before letting up inland. Typically, the beginning of coastal heat waves are associated with a loss of CLC, followed by a strong rebound of CLC starting close to the peak in heat wave intensity. The degree to which an inland heat wave is expressed at the coast is associated with the presence of these low clouds. Inland heat waves that have very little expression at the coast tend to have CLC present and an elevated inversion base height compared with other heat waves.
Inservice Examination and Testing Issues for Dynamic Restraints (Snubbers) in Nuclear Power Plants

This paper discusses recent issues related to the inservice examination and testing of dynamic restraints (snubbers) at U.S. nuclear power plants. The U.S. Nuclear Regulatory Commission (NRC) staff identified these issues during its review of examination and testing snubber programs and relief requests, as well as operating experience. This discussion includes information that could apply generically to the implementation of effective snubber programs at U.S. nuclear power plants.Paper published with permission.Compilation Copyright © 2017 ASME
IterativE Grammar-Based Framework for Discovering Variable-Length Time Series Motifs

In recent years, finding repetitive similar patterns in time series has become a popular problem. These patterns are called time series motifs. Recent studies show that using grammar compression algorithms to find repeating patterns from the symbolized time series holds promise in discovering approximate motifs with variable length. However, grammar compression algorithms are traditionally designed for string compression. Therefore, existing work on grammar induction has not fully utilized much available information that can be used to enhance the performance of the algorithms. In this work, an iterative framework based on grammar induction is proposed. In each iteration, a revision operator called Noise Reduction Operator is applied to revise the symbolized time series string based on the rules returned from a base grammar induction algorithm. In our experiments, we show that the proposed work can find motifs of the same quality, with much faster running time compared to the state-of-the-art variable-length exact motif discovery algorithm in real world time series data.
Understanding the Lomb–Scargle Periodogram

The Lomb-Scargle periodogram is a well-known algorithm for detecting and characterizing periodic signals in unevenly-sampled data. This paper presents a conceptual introduction to the Lomb-Scargle periodogram and important practical considerations for its use. Rather than a rigorous mathematical treatment, the goal of this paper is to build intuition about what assumptions are implicit in the use of the Lomb-Scargle periodogram and related estimators of periodicity, so as to motivate important practical considerations required in its proper application and interpretation.
Sunlight and Protection Against Influenza.

Recent medical literature suggests that vitamin D supplementation protects against acute respiratory tract infection. Humans exposed to sunlight produce vitamin D directly. This paper investigates how differences in sunlight, as measured over several years across states and during the same calendar week, affect influenza incidence. We find that sunlight strongly protects against getting influenza. This relationship is driven almost entirely by the severe H1N1 epidemic in fall 2009. A 10% increase in relative sunlight decreases the influenza index in September or October by 1.1 points on a 10-point scale. A second, complementary study employs a separate data set to study flu incidence in counties in New York State. The results are strongly in accord.
When Do Ethnic Communities Affect Foreign Location Choice? Dual Entry Strategies of Korean Banks in China

Research shows that firms tend to expand into foreign locations with sizeable co-ethnic communities. Yet many cases exist in which the ethnic community influences the investment choice of the same firm in one location but not in another. We offer an institutional lens to explain this heterogeneity in location choice. Ethnic groups function like informal institutions that facilitate transactions between a foreign firm and customers, suppliers, and information providers through interpersonal exchange. Relying on ethnic communities to mediate transactions in foreign markets is valuable but limited by the relatively small scale of these communities. In contrast, relying on formal institutions allows firms to expand more broadly into the foreign market because the impersonal exchange inherent in formal governance is more scalable. This is manifested in ‘dual entry strategies’ by which ethnic communities have a significantly stronger influence on location choice in places with unreliable (weak and unstable) for...
Governing Through Patronage: The Rise of NGOs and the Fall of Civil Society in Palestine and Morocco

This article examines foreign aid and government funding to NGOs as forms of patronage and explores the impact of such funding on the nature and role of civil society. Using qualitative research from Palestine and Morocco, we argue that patronage transforms NGOs into apparatuses of governing. NGOs become key sites for the exercise of productive power through the technologies of professionalization, bureaucratization, and upward accountability. The article explores how this transformation of NGOs depoliticizes their work while undermining their role as change agents within civil society. The findings have implications for understanding the transformation of NGOs, the relationship between patrons and their grantees, and, finally, for exploring the limitations of NGOs as vehicles for social change in sensitive political environments.
Are Cardiovascular Risk Factors Stronger Predictors of Incident Cardiovascular Disease in U.S. Adults With Versus Without a History of Clinical Depression

Background Several mechanisms underlying the depression-to-cardiovascular disease (CVD) relationship have been proposed; however, few studies have examined whether depression promotes CVD through potentiating traditional cardiovascular risk factors. Purpose To test the combined influence of three cardiovascular risk factors and lifetime depressive disorder on incident CVD in a large, diverse, and nationally representative sample of U.S. adults. Methods Respondents were 26,840 adults without baseline CVD who participated in Waves 1 (2001-2002) and 2 (2004-2005) of the National Epidemiologic Survey on Alcohol and Related Conditions. Lifetime depressive disorder, tobacco use, hypertension, and incident CVD were determined from structured interviews, and body mass index (BMI) was computed from self-reported height and weight. Results Logistic regression models predicting incident CVD (1,046 cases) revealed evidence of moderation, as the interactions between lifetime depressive disorder and current tobacco use (p = .002), hypertension (p < .001), and BMI (p = .031) were significant. The Former Tobacco Use × Lifetime Depressive Disorder interaction was not significant (p = .85). In models stratified by lifetime depressive disorder, current tobacco use (OR = 1.78, 95% CI = 1.36-2.32, p < .001 vs. OR = 1.41, 95% CI = 1.24-1.60, p < .001), hypertension (OR = 2.46, 95% CI = 1.98-3.07, p < .001 vs. OR = 1.39, 95% CI = 1.28-1.51, p < .001), and BMI (OR = 1.10, 95% CI = 1.01-1.20, p = .031 vs. OR = 1.03, 95% CI = 0.99-1.07, p = .16) were stronger predictors of incident CVD in adults with versus without a lifetime depressive disorder. Conclusions Our findings suggest that amplifying the atherogenic effects of traditional cardiovascular risk factors may be yet another candidate mechanism that helps to explain the excess CVD risk of people with depression.
Hardness of Non-interactive Differential Privacy from One-Way Functions

A central challenge in differential privacy is to design computationally efficient non-interactive algorithms that can answer large numbers of statistical queries on a sensitive dataset. That is, we would like to design a differentially private algorithm that takes a dataset \(D \in X^n\) consisting of some small number of elements n from some large data universe X, and efficiently outputs a summary that allows a user to efficiently obtain an answer to any query in some large family Q.
Resource Allocation and HARQ Optimization for URLLC Traffic in 5G Wireless Networks

5G wireless networks are expected to support ultra-reliable low latency communications (URLLC) traffic which requires very low packet delays (<; 1 ms) and extremely high reliability (~99.999%). In this paper, we focus on the design of a wireless system supporting downlink URLLC traffic. Using a queuing network-based model for the wireless system, we characterize the effect of various design choices on the maximum URLLC load it can support, including: 1) system parameters such as the bandwidth, link SINR, and QoS requirements; 2) resource allocation schemes in orthogonal frequency-division multiple access (OFDMA)-based systems; and 3) hybrid automatic repeat request schemes. Key contributions of this paper which are of practical interest are: 1) study of how the minimum required system bandwidth to support a given URLLC load scales with associated QoS constraints; 2) characterization of optimal OFDMA resource allocation schemes which maximize the admissible URLLC load; and 3) optimization of a repetition code-based packet re-transmission scheme.
PREDICTIVE FACTORS OF SHOULDER ARTHROPLASTY FAILURE: MY CRYSTAL BALL

There is nothing going to ruin your day like a complication after shoulder arthroplasty, either hemiarthroplasty (HA) anatomical (TSA) or reverse arthroplasty (RTSA). While complications are fortunately uncommon with anatomical shoulder arthroplasty (approximately 8% but as high as 40%), the complication rate for RTSA has been reported as high as 70%. Most complications are multifactorial and cannot all be blamed on the patient. Basically you do not want to operate upon a young patient who is an insulin dependent diabetic, has an ASA of 3 or 4, who smokes, has HIV disease and has a BMI over 40. The most common predictors of failure are determined by the indication for surgery, the type of implant used and the skill of the surgeon. The major risk factors for HA are eccentric glenoids, young age and rotator cuff failure. The biggest risk factors for TSA are metal backed glenoid components, younger age of the patient, rotator cuff pathology and insufficient glenoid bone. The major risk factors for RTSA are the type of component used (Grammont type versus lateral center of rotation designs) and the indication for surgery. Infection risks include previous infected arthroplasty, previous joint infection, immunosuppression (e.g. steroid use, insulin dependent diabetes, HIV disease), ASA 3 or 4 and higher BMI (i.e. over 40). Not all of these risk factors can be prevented in patients but informed consent is critical to the patient understanding the potential outcomes of their surgery.
A Phase 2 clinical trial of PF-05212377 (SAM-760) in subjects with mild to moderate Alzheimer’s disease with existing neuropsychiatric symptoms on a stable daily dose of donepezil

Symptomatic benefits have been reported for 5-HT6 receptor antagonists in Alzheimer’s disease (AD) trials. SAM-760 is a potent and selective 5-HT6 receptor antagonist that has demonstrated central 5-HT6 receptor saturation in humans at a dose of 30 mg. This was a randomized, double-blind, placebo-controlled, parallel-group, multicenter trial evaluating the efficacy and safety of SAM-760 30 mg once daily (QD) for 12 weeks in subjects with AD on a stable regimen of donepezil 5 to 10 mg QD. The study included an interim analysis with stopping rules for futility or efficacy after 180 subjects completed the week 12 visit. Up to 342 subjects with AD (Mini-Mental State Examination (MMSE) score 10–24) and neuropsychiatric symptoms (Neuropsychiatric Inventory (NPI) total score ≥ 10) were to be enrolled if the study continued after the interim analysis. After a 4-week, single-blind, placebo run-in period, subjects entered the 12-week double-blind period and were randomized to either SAM-760 or placebo. The primary and key secondary efficacy endpoints were the change from baseline in Alzheimer’s Disease Assessment Scale-cognitive subscale (ADAS-cog13) and NPI total scores. Mixed models for repeated measures were used to analyze the data. At the interim analysis, when 186 subjects had been randomized and 163 had completed the week 12 visit, the study met futility criteria and was stopped. The mean week 12 treatment difference was 0.70 points (P = 0.43) for ADAS-cog13 and 2.19 points (P = 0.20) for NPI score, both of which were numerically in favor of placebo. Other secondary endpoints did not demonstrate any significant benefit for SAM-760. In total, 46.2% of SAM-760 subjects reported adverse events (AE) versus 44.7% for placebo, and there were 5 (5.5%) serious AEs in the SAM-760 group versus 3 (3.2%) for placebo. There were two deaths, one prior to randomization and one in the SAM-760 group (due to a traffic accident during washout of active treatment). SAM-760 was safe and well tolerated, but there was no benefit of SAM-760 on measures of cognition, neuropsychiatric symptoms, or daily function. Differences in trial design, study population, region, or pharmacological profile may explain differences in outcome compared with other 5-HT6 receptor antagonists. Clinicaltrials.gov, NCT01712074 . Registered 19 October 2012.
Assessing hurricane rainfall mechanisms using a physics-based model: Hurricanes Isabel (2003) and Irene (2011)

AbstractWe examine a recently-developed physics-based tropical cyclone rainfall (TCR) model and apply it to assess the mechanisms that dominate the magnitude and spatial distribution of TC rainfall, with Hurricanes Isabel (2003) and Irene (2011) as study cases. We evaluate the TCR model using Weather and Research Forecasting (WRF) model simulations. TCR-generated rainfall fields for the two storms compare well with WRF estimates in terms of both azimuthal mean and spatial distributions. When coupled with a hydrologic model, TCR generates flood peaks over the Delaware River basin for Irene as accurately as WRF. TCR accounts for four major rainfall mechanisms: surface frictional convergence, vortex stretching, interaction of the storm with topography, and interaction of the storm with large-scale baroclinity. We show that these rainfall mechanisms affected the rainfall pattern differently for Isabel and Irene. Frictional convergence is the dominant factor, while other mechanisms are also significant. The fr...
Automated mound detection using lidar and object-based image analysis in Beaufort County, South Carolina

ABSTRACTThe study of precontact anthropogenic mounded features—earthen mounds, shell heaps, and shell rings—in the American Southeast is stymied by the spotty distribution of systematic surveys across the region. Many extant, yet unidentified, archaeological mound features continue to evade detection due to the heavily forested canopies that occupy large areas of the region, making pedestrian surveys difficult and preventing aerial observation. Object-based image analysis (OBIA) is a tool for analyzing light and radar (lidar) data and offers an inexpensive opportunity to address this challenge. Using publicly available lidar data from Beaufort County, South Carolina, and an OBIA approach that incorporates morphometric classification and statistical template matching, we systematically identify over 160 previously undetected mound features. This result improves our overall knowledge of settlement patterns by providing systematic knowledge about past landscapes.
Land Fragmentation and Food Insecurity in Ethiopia

This paper revisits the economic consequences of land fragmentation, taking seriously concerns regarding the exogeneity of fragmentation, its measurement and the importance of considering impacts in terms of welfare metrics. Using data that are well-suited to addressing these issues, the analysis finds that land fragmentation reduces food insecurity. This result is robust to how fragmentation is measured and to how exogeneity concerns are addressed. Further, the paper finds that land fragmentation mitigates the adverse effects of low rainfall on food security. This is because households with diverse parcel characteristics can grow a greater variety of crop types.
Pancreatic ductal adenocarcinoma cell secreted extracellular vesicles containing ceramide-1-phosphate promote pancreatic cancer stem cell motility

The high mortality rate associated with pancreatic ductal adenocarcinoma (PDAC) is in part due to lack of effective therapy for this highly chemoresistant tumor. Cancer stem cells, a subset of cancer cells responsible for tumor initiation and metastasis, are not targeted by conventional cytotoxic agents, which renders the identification of factors that facilitate cancer stem cell activation useful in defining targetable mechanisms. We determined that bioactive sphingolipid induced migration of pancreatic cancer stem cells (PCSC) and signaling was specific to ceramide-1-phosphate (C1P). Furthermore, PDAC cells were identified as a rich source of C1P. Importantly, PDAC cells express the C1P converting enzyme ceramide kinase (CerK), secrete C1P-containing extracellular vesicles that mediate PCSC migration, and when co-injected with PCSC reduce animal survival in a PDAC peritoneal dissemination model. Our findings suggest that PDAC secrete C1P-containing extracellular vesicles as a means of recruiting PCSC to sustain tumor growth therefore making C1P release a mechanism that could facilitate tumor progression.
Nevada's Medicaid expansion and admissions for ambulatory care-sensitive conditions.

OBJECTIVES In January 2014, Nevada became 1 of the 32 states that have expanded Medicaid under the Affordable Care Act. As a result of the expansion, 276,400 additional Nevada residents received Medicaid insurance. The objectives of this paper were to examine the impact of Nevada's Medicaid expansion on changes in rates of hospital admissions for ambulatory care-sensitive conditions (ACSCs), which are potentially preventable with good access to outpatient medical care, and to examine the racial/ethnic disparities in such rates. STUDY DESIGN We used complete inpatient discharge data (for the years 2012, 2013, and 2014, and the first 3 quarters of 2015) from all nonfederal acute care community hospitals in Nevada. METHODS We employed pooled cross-sectional design with a difference-in-differences approach to identify overall and race/ethnicity-specific changes in admissions for ACSCs, adjusted for secular trends unrelated to expansion. We examined admissions for ACSCs among adults aged 18 to 64 years (those most likely to have been affected by the reform) admitted for overall, acute, and chronic ACSC composites in the 24 months before and 21 months after the date on which expansion was implemented. RESULTS After adjusting for confounders, we found that Hispanic patients with Medicaid were more likely to be admitted for ACSCs after Nevada's Medicaid expansion (overall quality composite: odds ratio [OR], 1.20; P = .05; chronic quality composite: OR, 1.34; P = .02). CONCLUSIONS This analysis provides evidence that Medicaid expansion may have limited potential to reduce the disparities in rates of hospital admissions for ACSCs. In Nevada, additional efforts might be needed to improve access to outpatient care and reduce preventable admissions.
Treatment decisions and employment of breast cancer patients: Results of a population-based survey.

10052Background: Many patients with breast cancer work for pay at time of diagnosis, and the treatment plan may threaten their livelihood. Given rapidly evolving policies, evidence, and treatment o...