cssi/SciSciGPT-SciSciNet huggingface dataset:
Supervisory switching control of an unmanned surface vehicle

A novel method to determine the switching of controllers to increase the performance of a system is presented. Three controllers are utilized to capture three “behaviors” representative of unmanned surface vehicles (USVs). An underactuated nonlinear controller is derived to transit the vehicle between locations; a fully-actuated nonlinear controller is given to station-keep the vehicle at a setpoint; and a linear anti-windup controller is presented for the reversing mode of operation. Given a trajectory to follow, a performance-based supervisory switching control system (PBSSC) dictates the switching between controllers to improve system performance. Experimental results are shown that indicate that the PBSSC system is able to mitigate errors in pose better than any of the individual controllers.
Empirical Tools and Competition Analysis: Past Progress and Current Problems

I review a subset of the empirical tools available for competition analysis. The tools discussed are those needed for the empirical analysis of; demand, production efficiency, product repositioning, and the evolution of market structure. Where relevant I start with a brief review of tools developed in the 1990’s that have recently been incorporated into the analysis of actual policy. The focus is on providing an overview of new developments; both those that are easy to implement, and those that are not quite at that stage yet show promise.
Present Status and Recent Developments of the Twisted Stacked-Tape Cable Conductor

The high magnetic field performance of a 40-tape twisted stacked-tape cable (TSTC) conductor made of 4-mm-width 0.1-mm-thick REBCO tapes was successfully tested. The critical current was 6.0 kA, with the n-value of 35, at 4.2 K with a background field of 17 T. No cyclic load effect was observed between 10 and 17 T with the maximum Lorentz load of 102 kN/m. Various issues, such as sample length, nonuniformity of termination resistances, and soldered joint of a coated tape cable, with regard to a TSTC conductor are discussed. Large-scale conductor designs of various scalable TSTC conductors are discussed, taking into account current densities and stabilizers.
Normal forms on contracting foliations: smoothness and homogeneous structure

In this paper we consider a diffeomorphism f of a compact manifold \(\mathcal {M}\) which contracts an invariant foliation W with smooth leaves. If the differential of f on TW has narrow band spectrum, there exist coordinates \({\mathcal {H}}_x:W_x\rightarrow T_xW\) in which \(f|_W\) has polynomial form. We present a modified approach that allows us to construct maps \({\mathcal {H}}_x\) that depend smoothly on x along the leaves of W. Moreover, we show that on each leaf they give a coherent atlas with transition maps in a finite dimensional Lie group. Our results apply, in particular, to \(C^1\)-small perturbations of algebraic systems.
Cyclohexanones by Rh-Mediated Intramolecular C–H Insertion

Some long chain α-aryl α-diazo ketones under Rh catalysis cyclize efficiently to the corresponding cyclohexanones. This is in marked contrast to the cyclizations of α-diazo β-ketoesters, which consistently deliver cyclopentanone products.
Scope and limitations of 2-deoxy- and 2,6-dideoxyglycosyl bromides as donors for the synthesis of β-2-deoxy- and β-2,6-dideoxyglycosides.

It is shown that 2-deoxy- and 2,6-dideoxyglycosyl bromides can be prepared in high yield (72–94%) and engaged in glycosylation reactions with β:α selectivities ≥6:1. Yields of product are 44–90%. Fully armed 2-deoxyglycoside donors are viable, while 2,6-dideoxyglycosides require one electron-withdrawing substituent for high efficiency and β-selectivity. Equatorial C-3 ester protecting groups decrease β-selectivity, and donors bearing an axial C-3 substituent are not suitable. The method is compatible with azide-containing donors and acid-sensitive functional groups.
Using Time Strain Volume For Improved 4D Interpretation: Methods And Case Studies

A new method has been developed to derive time strain volumes from multiple time shift volumes. A workflow has been proposed to merge time strain volume with 4D difference seismic volume to derive Broadband Time Lapse volume (BBT). The workflow is simple and cost efficient for maximizing the 4D information.
Memristive Boltzmann machine: A hardware accelerator for combinatorial optimization and deep learning

The Boltzmann machine is a massively parallel computational model capable of solving a broad class of combinatorial optimization problems. In recent years, it has been successfully applied to training deep machine learning models on massive datasets. High performance implementations of the Boltzmann machine using GPUs, MPI-based HPC clusters, and FPGAs have been proposed in the literature. Regrettably, the required all-to-all communication among the processing units limits the performance of these efforts. This paper examines a new class of hardware accelerators for large-scale combinatorial optimization and deep learning based on memristive Boltzmann machines. A massively parallel, memory-centric hardware accelerator is proposed based on recently developed resistive RAM (RRAM) technology. The proposed accelerator exploits the electrical properties of RRAm to realize in situ, fine-grained parallel computation within memory arrays, thereby eliminating the need for exchanging data between the memory cells and the computational units. Two classical optimization problems, graph partitioning and boolean satisfiability, and a deep belief network application are mapped onto the proposed hardware. As compared to a multicore system, the proposed accelerator achieves 57x higher performance and 25x lower energy with virtually no loss in the quality of the solution to the optimization problems. The memristive accelerator is also compared against an RRAM based processing-in-memory (PIM) system, with respective performance and energy improvements of 6.89x and 5.2x.
ACCELERATION OF THERMAL PROTONS BY GENERIC PHENOMENOLOGICAL MECHANISMS

We investigate heating and acceleration of protons from a thermal gas with a generic diffusion and acceleration model, and subject to Coulomb scattering and energy loss, as was done by Petrosian & East for electrons. As protons gain energy their loss to electrons becomes important. Thus, we need to solve the coupled proton–electron kinetic equation. We numerically solve the coupled Fokker–Planck equations and compute the time evolution of the spectra of both particles. We show that this can lead to a quasi-thermal component plus a high-energy nonthermal tail. We determine the evolution of the nonthermal tail and the quasi-thermal component. The results may be used to explore the possibility of inverse bremsstrahlung radiation as a source of hard X-ray emissions from hot sources such as solar flares, accretion disk coronas, and the intracluster medium of galaxy clusters. We find that the emergence of nonthermal protons is accompanied by excessive heating of the entire plasma, unless the turbulence needed for scattering and acceleration is steeper than Kolmogorov and the acceleration parameters, the duration of the acceleration, and/or the initial distributions are significantly fine-tuned. These results severely constrain the feasibility of the nonthermal inverse bremsstrahlung process producing hard X-ray emissions. However, the nonthermal tail may be the seed particles for further re-acceleration to relativistic energies, say by a shock. In the Appendix we present some tests of the integrity of the algorithm used and present a new formula for the energy loss rate due to inelastic proton–proton interactions.
Hypotheses for Near-Surface Exchange of Methane on Mars

Abstract The Curiosity rover recently detected a background of 0.7 ppb and spikes of 7 ppb of methane on Mars. This in situ measurement reorients our understanding of the martian environment and its potential for life, as the current theories do not entail any geological source or sink of methane that varies sub-annually. In particular, the 10-fold elevation during the southern winter indicates episodic sources of methane that are yet to be discovered. Here we suggest a near-surface reservoir could explain this variability. Using the temperature and humidity measurements from the rover, we find that perchlorate salts in the regolith deliquesce to form liquid solutions, and deliquescence progresses to deeper subsurface in the season of the methane spikes. We therefore formulate the following three testable hypotheses. The first scenario is that the regolith in Gale Crater adsorbs methane when dry and releases this methane to the atmosphere upon deliquescence. The adsorption energy needs to be 36 kJ mol−1 t...
Approximating Bounded Occurrence Ordering CSPs

A theorem of Hastad shows that for every constraint satisfaction problem (CSP) over a fixed size domain, instances where each variable appears in at most O(1) constraints admit a non-trivial approximation algorithm, in the sense that one can beat (by an additive constant) the approximation ratio achieved by the naive algorithm that simply picks a random assignment. We consider the analogous question for ordering CSPs, where the goal is to find a linear ordering of the variables to maximize the number of satisfied constraints, each of which stipulates some restriction on the local order of the involved variables. It was shown recently that without the bounded occurrence restriction, for every ordering CSP it is Unique Games-hard to beat the naive random ordering algorithm.
A new assay for the determination of phosphoribosylamine.

Glutamine phosphoribosylpyrophosphate amidotransferase (amidophosphoribosyltransferase, E.C.2.4.2.14) catalyzes the initial reaction in purine biosynthesis de novo (Goldthwait, 1956; Hartman and Buchanan, 1957). The substrates of this reaction are phosphoribosylpyrophosphate (PP-ribose-P), glutamine and H2O; the products are phosphoribosylamine (PRA), glutamate and pyrophosphate (PPi). The regulatory properties of amidophosphoribosyltransferase suggest that it may be important in the control of purine biosynthesis (Wyngaarden, 1972; Holmes, et al., 1973; Holmes, Wyngaarden and Kelley, 1973), and as a consequence there has been considerable interest in the study of this enzyme.
Best-first AND/OR search for most probable explanations

The paper evaluates the power of best-first search over AND/OR search spaces for solving the Most Probable Explanation (MPE) task in Bayesian networks. The main virtue of the AND/OR representation of the search space is its sensitivity to the structure of the problem, which can translate into significant time savings. In recent years depth-first AND/OR Branch-and-Bound algorithms were shown to be very effective when exploring such search spaces, especially when using caching. Since best-first strategies are known to be superior to depth-first when memory is utilized, exploring the best-first control strategy is called for. The main contribution of this paper is in showing that a recent extension of AND/OR search algorithms from depth-first Branch-and-Bound to best-first is indeed very effective for computing the MPE in Bayesian networks. We demonstrate empirically the superiority of the best-first search approach on various probabilistic networks.
Middle Cranial Fossa Dehiscence as an Incidental Finding on CT

OBJECTIVES This retrospective chart review demonstrates that the prevalence of middle cranial fossa (MCF) dehiscence on computed tomography (CT) scans increases with age. METHODS High-resolution temporal bone CT scans, which had been obtained for any otologic complaint, were reviewed independent of all clinical history. Scans showing soft tissue, fluid, trauma, or previous operations were excluded. The CTs from 183 patients (296 ears) were reviewed, blinded for age and body mass index (BMI). The MCF floor was divided into 7 regions and systematically inspected. Ages and BMIs of the patients were subsequently extracted from the medical record. RESULTS Logistic regression analysis confirmed increasing MCF dehiscence with age (P 30 (P < .003, P < .04, P = .03). CONCLUSION The increase of middle cranial fossa dehiscence with respect to age is statistically significant. Over all ages, approximately 32% of ears show dehiscence. Over 60 years, approximately 55% show dehiscence. The odds of having dehiscence double with a 10-year difference in age. The most common sites along the MCF floor are in the epitympanum over the malleus head and the additus ad antrum. There was a statistically significant increase in MCF dehiscence with age when patients with equivalent BMIs are compared.
Sepsis Induces Hematopoietic Stem Cell Exhaustion and Myelosuppression through Distinct Contributions of TRIF and MYD88

Toll-like receptor 4 (TLR4) plays a central role in host responses to bacterial infection, but the precise mechanism(s) by which its downstream signaling components coordinate the bone marrow response to sepsis is poorly understood. Using mice deficient in TLR4 downstream adapters MYD88 or TRIF, we demonstrate that both cell-autonomous and non-cell-autonomous MYD88 activation are major causes of myelosuppression during sepsis, while having a modest impact on hematopoietic stem cell (HSC) functions. In contrast, cell-intrinsic TRIF activation severely compromises HSC self-renewal without directly affecting myeloid cells. Lipopolysaccharide-induced activation of MYD88 or TRIF contributes to cell-cycle activation of HSC and induces rapid and permanent changes in transcriptional programs, as indicated by persistent downregulation of Spi1 and CebpA expression after transplantation. Thus, distinct mechanisms downstream of TLR4 signaling mediate myelosuppression and HSC exhaustion during sepsis through unique effects of MyD88 and TRIF.
Classification and diagnosis of diabetes mellitus in children and adolescents.

THERE HAS BEEN substantial alteration of the perception of the clinical spectrum of diabetes and its etiologic heterogeneity in the past decade." This growth of knowledge has been important for both pediatric and adult patient populations. In 1979, the National Diabetes Data Group assembled international experts to revise classifications and nomenclature for diabetes mellitus in an effort to improve communication among practitioners and investigators and to incorporate newer concepts into a more appropriate terminology. In the deliberations of the National Diabetes Data Group, members of the Lawson Wilkins Pediatric Endocrine Society individually, and collectively, as the Committee on Diabetes, contributed advice which was incorporated into the final report. The purpose of this communication is to convey those portions of the National Diabetes Data Group report 1 pertinent to pediatric practice. The NDDG report did not deal with therapy.
Controlling Viscous Fingering Using Time-Dependent Strategies

Control and stabilization of viscous fingering of immiscible fluids impacts a wide variety of pressure-driven multiphase flows. We report theoretical and experimental results on a time-dependent control strategy by manipulating the gap thickness b(t) in a lifting Hele-Shaw cell in the power-law form b(t)=b(1)t(1/7). Experimental results show good quantitative agreement with the predictions of linear stability analysis. By choosing the value of a single time-independent control parameter, we can either totally suppress the viscous fingering instability or maintain a series of nonsplitting viscous fingers during the fluid displacement process. In addition to the gap thickness of a Hele-Shaw cell, time-dependent control strategies can, in principle, also be placed on the injection rate, viscosity of the displaced fluid, and interfacial tension between the two fluids.
Starting open source collaborative innovation: the antecedents of network formation in community source

Specific needs in the area of enterprise applications have led to a new type of collaborative open source innovation development across institution borders: community source. We use the Kuali community source network, a jointly managed, border-spanning organization that supplies the institutions that created it, to describe how community source works. This study builds a theoretical basis for understanding the individual and institutional factors affecting community source network formation and the decision by organizations to join a community source network. We identify eight antecedents of decisions about forming or joining community source initiatives: motives, learning, trust, norms and monitoring, institutional similarity, external funding, hostile external environment and information technology. © 2016 Blackwell Publishing Ltd
The approximation of parabolic equations involving fractional powers of elliptic operators

We study the numerical approximation of a time dependent equation involving fractional powers of an elliptic operator L defined to be the unbounded operator associated with a Hermitian, coercive and bounded sesquilinear form on H 0 1 ( ź ) . The time dependent solution u ( x , t ) is represented as a Dunford-Taylor integral along a contour in the complex plane.The contour integrals are approximated using sinc quadratures. In the case of homogeneous right-hand-sides and initial value v , the approximation results in a linear combination of functions ( z q I - L ) - 1 v ź H 0 1 ( ź ) for a finite number of quadrature points z q lying along the contour. In turn, these quantities are approximated using complex valued continuous piecewise linear finite elements.Our main result provides L 2 ( ź ) error estimates between the solution u ( ź , t ) and its final approximation. Numerical results illustrating the behavior of the algorithms are provided.
Predictors of prostate cancer screening using Andersen’s Behavioral Model of Health Services Use

Abstract Purpose The purposes of the study were to examine the prevalence of prostate cancer screening (PCS) in the United States and to identify predictors of PCS guided by Andersen’s Behavioral Model of Health Services Use (ABM). Methods PCS rates were analyzed in men (aged ≥40 y) using 2014 data from the Behavioral Risk Factor Surveillance System. Descriptive analysis was conducted using sampling weights to determine the prevalence of PCS (i.e., had a prostate-specific antigen test). Multiple logistic regression within the framework of ABM was used to identify predictors of PCS. The ABM variables of predisposing (e.g., age), enabling (e.g., health insurance), and need (e.g., comorbidities) comprised the independent variables. Results Among the 131,415 men, 62.4% (N = 82,014) reported that they had a prostate-specific antigen test in the last 2 years. Among predisposing factors, age, education, income, and employment status were significantly associated with undergoing PCS. Informed decision-making process, health care coverage, regular health care provider, and length of time since last routine checkup were significant enabling factors. Health care provider recommendation and previous cancer diagnosis were significant need factors. Conclusions Most older men in the United States had previously engaged in PCS. Several ABM variables were predictive of PCS and should be considered when developing future strategies to encourage PCS in at-risk men with the recommended life expectancies. Such strategies should also ensure that the decision to undergo PCS is an informed process between patients and their health care providers.
Reviving the Environmental Justice Agenda

Racial minorities and low-income populations receive an unequal burden of the pollution impacts in the United States, while obtaining fewer benefits of industrial development. Environmental justice (EJ) seeks to remedy this unequal distribution. Although overhaul of environmental laws would be a welcome approach among those advocating for improved environmental protection use of existing legal tools can make a significant contribution to reducing pollution and risk profiles. Progress through the Obama administration demonstrates that it is feasible to use existing legal tools to promote EJ, regardless of whether Congress adopts more proactive EJ laws in the future. In the face of legislative failure, federal activity to remedy unequal environmental impact burdens can be found at the administrative level—with the executive branch prodding federal agencies to use existing environmental and civil rights laws (among other tools) to reduce the environmental risks borne by racial minorities and low- income populations. In this article, I trace the efforts to address environmental justice through executive action, noting several accomplishments of the Obama administration to boost leadership, collaboration, and direct funding to EJ efforts. Notably, President Obama's acknowledgment of the rights of minority and low-income populations to a healthy living environment is supported by the development of data critically necessary to highlight the existing disparities and bring environmental justice actions to bear where they are necessary.
Evaluating Scale and Technical Efficiency among Farms and Ranches with a Local Market Orientation

In recent years, the growth in local food marketing channels has been significant. Most of the research in this field examining the economic implication of these trends has focused post-farmgate including supply chain analysis (e.g., Hardesty et al., 2014; King et al., 2010), regional economic impacts (e.g., Brown et al., 2014; Hughes et al., 2008; Jablonski et al., 2016) and consumer values and motivations that have driven demand (e.g., Costanigro, 2014; Lusk and Briggeman, 2009). To date, with the exception of a few case studies examining expenses and sales by channel assessment (LeRoux et al., 2010; Hardesty and Leff, 2010; Jablonski and Schmit, 2016) there has been little research that examines the impact on financial viability among farms selling through these markets. The goal of this paper is twofold: first, to identify the factors that have the greatest influence on the efficiency of farmers and ranchers that participate in local food systems, and second, to estimate the relationship between marketing strategy and farm financial efficiency, with a particular focus on variations across farm size. Our estimation of the stochastic production frontier suggests that scale, production enterprise specialty, market outlet choices, land ownership, and management of expenses have the greatest influence on producer financial efficiency. Our model suggests that scale has the largest impact on financial efficiency, providing evidence that, all else constant, the most important factor in the efficiency of direct market producers is scale. When profit is defined as operating profit, results indicate that marketing channel is not an important indicator of efficiency. But when profit is defined as return on assets, marketing channel is an important indicator of efficiency, albeit less than is scale. Results from this analysis indicate there are economies of scale associated with farms and ranches that sell through local and regional markets, and that scale rather than marketing channel has the largest influence on efficiency.
FINANCIAL TRANSACTION TAXES IN THEORY AND PRACTICE

We explore issues related to a financial transaction tax (FTT) in the United States. We trace the history and current practice of the tax in the United States and other countries, review evidence o...
Evaluation of the Aptima HIV-1 Quant Dx Assay using plasma and dried blood spots

HIV-1 RNA quantitation in plasma, or virus load testing, is the primary method by which the response to antiretroviral therapy is monitored. Here we describe evaluation of the Aptima HIV-1 Quant Dx assay (Aptima) performed on the automated Panther system. The clinical performance of Aptima was compared to that of the Cobas AmpliPrep/Cobas TaqMan HIV-1 Test v2.0 (CAP/CTM) using 162 EDTA plasma samples collected from patients undergoing HIV-1 monitoring. Overall agreement was 84.0% (136/162), with a kappa statistic of 0.723 (standard error, 0.047; 95% confidence interval [CI], 0.630 to 0.815), indicating substantial agreement. Using the 86 clinical samples quantifiable by both methods, Passing-Bablok regression revealed a regression line of Y = (1.069 × X) - 0.346 (95% CI of the slope [1.003 to 1.139] and intercept [-0.666 to -0.074]), and Bland-Altman analysis demonstrated a mean difference (Aptima-CAP/CTM) of -0.075 log10 copies/ml (95% limits of agreement of -0.624 to 0.475), consistent with negative bias. Comparison of Aptima results for paired dried blood spot (DBS) and plasma specimens archived from participants in the Peninsula AIDS Research Cohort Study (PARC) demonstrated an overall agreement of 94.7% (90/95) when 1,000 copies/ml was used as the threshold. In conclusion, the Aptima HIV-1 Quant Dx assay provides a suitable alternative for HIV-1 monitoring in plasma and DBS.
THERE IS A DRAMATIC INCREASE IN PAEDIATRIC PELVIC PYOMYOSITIS IN THE UNITED KINGDOM

Tropical pyomyosistis is an uncommon condition in the United Kingdom. Early diagnosis and appropriate treatment are crucial for a good outcome. We had seen 13 cases in our previously published series from 1998 to 2009. This is an update showing a significantly increased incidence from 2010 to 2016. A retrospective review of all cases of pelvic pyomyositis in our centre from January 2010 to April 2016 was undertaken from case notes and radiology reports. All children with clinical and radiographic evidence of pyomyositis were included. Since our previous publication we had changed our practice to get an MRI scan in all children who presented with a limp, fever and raised inflammatory markers, and had no effusion in the hip ultrasound scan. We identified 24 children with a mean age of 7 years (range, 1 week to 14 years). MSSA ( Methicillin-Sensitive Staphylococcus aureus ) was the most common cultured organism (n=8). Median hospital stay was 9 days (3 to 12). Obturator internus was the most common muscle affected. All patients had appropriate antibiotics with 2 patients requiring surgical drainage of abscesses. The majority of children (n=22) showed a complete recovery with antibiotics only. Incidence of pyomyositis has increased dramatically in our population and early diagnosis can result in a good outcome. We recommend MRI scan in all patients who present with a clinical picture of septic arthritis of the hip but with no effusion.
Pseudoparticle parameters for arbitrary gauge groups

The number of parameters entering a Euclidean Yang-Mills solution with topological charge $k$ is determined for a theory constructed from an arbitrary Lie group $G$. It is shown that this number is precisely that required to specify the position, scale, and relative group orientation of $k$ independent solutions each with minimum topological charge 1. Such minimal single-pseudoparticle solutions can be obtained by embedding the familiar ${\mathrm{SU}}_{2}$ pseudoparticle of Belavin et al. into the general Lie group.
The Decision to Carry: The Effect of Crime on Concealed-Carry Applications

Despite persistent debate on the role of concealed-carry legislation, decisions to legally carry concealed handguns are not well understood. Using/detailed data on concealed-carry permit applications, we explore whether individuals apply for concealed-carry permits in response to crime. We find that recent homicides increase applications in areas relatively near to the incident. The effects are driven by gun-related homicides and are more pronounced for white, male, and Republican applicants. We also find suggestive evidence that applicants are more responsive when they share a demographic characteristic with the homicide victim. The results further indicate that applications after recent homicides are more likely to be renewed, consistent with persistent precautionary behaviors. Our findings provide causal evidence that crime risk influences individual decisions regarding legal gun use. [End Page 1121] [ABSTRACT FROM AUTHOR]
The Life Cycle Model, Replacement Rates, and Retirement Income Adequacy

The key insight of the life cycle model in economics is that a household’s consumption at any given time is determined not so much by its current income as by the total income available to the household over its lifetime. A replacement rate can be a useful tool in approximating the life cycle model’s predictions for how households prepare for retirement. The Social Security Administration’s Office of the Chief Actuary (SSA OACT) publishes two different calculations of retirement income replacement rates, each of which finds that Social Security benefits replace about 40% of a typical retiree’s pre-retirement earnings. Some interpret these figures as indicating that Social Security benefits are insufficiently generous and that U.S. households’ total retirement saving is inadequate. But SSA OACT’s two methods for calculating replacement rates both violate the life cycle model in a meaningful way. SSA OACT’s career-average earnings replacement rates, in which lifetime earnings are first indexed upward by the rate of economywide wage growth, exaggerates by roughly one-fifth the real value of earnings available to a household for consumption over its lifetime. This overstatement lowers a household’s measured ability to replace their pre-retirement earnings. SSA OACT’s final-earnings replacement rates effectively compare Social Security retirement benefits to pre-retirement earnings only in the years in which the individual worked, ignoring the life cycle model’s prediction that household consumption is a function of long-term average earnings, including years in which a household member was not employed. A replacement-rate calculation more consistent with the life cycle model would compare retirement income to an average of real earnings calculated over a significant number of years. Such an approach would find substantially higher replacement rates for the typical retiree. It is important both for Social Security policy and the analysis of overall retirement savings adequacy that replacement-rate calculations build on the insights of the life cycle model that guides most economic analysis of retirement saving.
When Does Improved Targeting Increase Revenue

In second-price auctions, we find that improved targeting via enhanced information disclosure decreases revenue when there are two bidders and increases revenue if there are at least four symmetric bidders with values drawn from a distribution with a monotone hazard rate. With asymmetries, improved targeting increases revenue if the most frequent winner wins less than 30.4% of the time under a model in which shares are well defined, but can decrease revenue otherwise. We derive analogous results for position auctions. Finally, we show that revenue can vary nonmonotonically with the number of bidders who are able to take advantage of improved targeting.
Overcorrection of the inter-metatarsal angle in corrective hallux valgus osteotomy leads to an increase in intra-articular pressures of the 1st metatarsal-phalangeal joint: a biomechanical simulation

Introduction Despite the multiple patho-aetiological basis of Hallux valgus (HV), corrective osteotomy is a common and globally performed orthopaedic procedure. Over-correction of the inter-metatarsal angle (IMA), however, is not without consequence. Through increased joint pressures, over-correction may predispose to joint degeneration. Hypothesizing that over-correction leads to an increase in intra-articular joint pressures, we constructed a mechanical simulation of the 1st metatarsal-phalangeal joint. Methods The vector forces of Flexor Hallucis Longus, Extensor Hallucis Longus, Extensor Hallucis Brevis and Adductor Hallucis, acting upon the 1st proximal phalanx were simulated with tensioned weighted rope. A Foley catheter balloon inflated to 1.5ml, simulated intra-articular distractive vector forces. The joint was freely mobile. At 5° IMA intervals from 10° valgus to 15° varus, intrarticular pressures were recorded using a contact pressure (Graseby™, Hertfordshire, UK ) transducer attached to a calibrated manometer (Digitech Instruments™, Ulhasnagar, India ). At each angle, measurements were repeated five times with removal and recalibration of the pressure monitor after each measurement. Results A decline and subsequent increase in mean pressure was observed at each 5° interval from 10°valgus to neutral and then to 15° varus ( mean±s.d .; 48.02±5.67, 24.72±1.01, 12.34±0.84, 18.96±2.46, 32.88±5.06, 42.92±4.99 milibar for 10°, 5° valgus, neutral, 5°, 10°and 15° varus IMA). One-way analysis of variance with post-hoc Tukey multiple comparison test revealed a significant increase in pressure from neutral and 5° valgus to 10° and 15° varus ( p< 0.05 ). [First Metatarsal Phalangreal joint pressures] Conclusion This is the first description demonstrating increases in intrarticular pressures as the IMA tended from 5° to 15° varus, replicating inatrogenic Hallux Varus iatrogenically produced through osteotomy and over-correction of the IMA. Over-correction and increased intrarticular joint pressure may have an aetiological basis to post-operative 1st MTPJ degeneration. Over-correction is not a benign entity requiring consideration in Hallux Valgus corrective osteotomy.
The proper definition of noise figure of optical amplifiers

The noise figure definition currently in use for the characterization of optical amplifiers is criticised. Its shown that it is inconsistent with the IEEE standard established for electronic amplifiers. A noise figure definition is proposed that is consistent with the IEEE standard and that is shown to be superior to the one currently in use.
A business model for success: Enterprises serving the base of the pyramid with off-grid solar lighting

Abstract Basic electric service is essential to sustainable development, yet for remote rural areas, connecting to an electric grid can be economically and geographically unfeasible. Firms have sought to bring basic electric service to isolated and impoverished rural areas using off-grid solar lights and solar home systems, but often meet challenges common to base of the pyramid (BOP) markets. This article examines the intersection of theories related to successful business models for enterprises serving the base of the pyramid and studies of off-grid renewable energy enterprises. It identifies relevant and overlapping themes, and creates a framework for a successful business model that includes four primary components: community interaction; partnerships; local capacity building; and addressing barriers unique to the off-grid market, including financing, education, and development of distribution networks.
Curvature-driven morphing of non-Euclidean shells

We investigate how thin structures change their shape in response to non-mechanical stimuli that can be interpreted as variations in the structure’s natural curvature. Starting from the theory of non-Euclidean plates and shells, we derive an effective model that reduces a three-dimensional stimulus to the natural fundamental forms of the mid-surface of the structure, incorporating expansion, or growth, in the thickness. Then, we apply the model to a variety of thin bodies, from flat plates to spherical shells, obtaining excellent agreement between theory and numerics. We show how cylinders and cones can either bend more or unroll, and eventually snap and rotate. We also study the nearly isometric deformations of a spherical shell and describe how this shape change is ruled by the geometry of a spindle. As the derived results stem from a purely geometrical model, they are general and scalable.
Who will vote quadratically? Voter turnout and votes cast under quadratic voting

Who will vote quadratically in large-N elections under quadratic voting (QV)? First, who will vote? Although the core QV literature assumes that everyone votes, turnout is endogenous. Drawing on other work, we consider the representativeness of endogenously determined turnout under QV. Second, who will vote quadratically? Conditional on turning out, we examine reasons that, in large-N elections, the number of votes that an individual casts may deviate substantially from that under pure, rational QV equilibrium play. Because turnout itself is driven by other factors, the same determinants may influence how voters who do turn out choose the quantity of votes to cast. Independently, the number of votes actually cast may deviate dramatically from pure QV predictions because of the complex and refined nature of equilibrium play. Most plausibly, voting behavior and outcomes would be determined predominately by social and psychological forces, would exhibit few of the features emphasized in the analysis of hyper-rational equilibrium play, and would have consequential properties that require a different research agenda to bring into focus. Some of our analysis also has implications for voting behavior under other procedures, including one person, one vote.
Magnetohydrodynamic power generation

Magnetohydredynamic (mhd) power generation promises to be more efficient than present methods of generation. The ideas behind mhd generation and their development leading to the experimental generators that have been built are discussed. The extent of research into the many problems that remain to be solved in order that mhd power generation may become a commercial proposition is mentioned. (auth)
The control of high-speed variable-reluctance generators in electric power systems

This work studies the control of a direct-current (DC) electric power system that is sourced by a variable-reluctance generator. The power system includes the generator and its switching inverter, a filtering capacitor, a distribution network and an electrical load. The network comprises a series resistor and inductor, while the load comprises a parallel resistor, capacitor and power sink. The voltage at the load is regulated by adjusting the rotor angles at which the inverter switches. Both steady-state and transient performance are considered. Simulations are provided to illustrate performance. >
The National Ignition Facility and the Promise of Inertial Fusion Energy

The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) in Livermore, CA, is now operational. The NIF is the world’s most energetic laser system capable of produci...
Some applications of wireless communications in Intelligent Vehicle Highway Systems

Intelligent Vehicle Highway Systems (IVHS) have generated a new challenge for communications industries. This is particularly true for mobile communications, since most essential IVHS communications links require wireless and mobile transmission. The IVHS and its major components are described. A generic block diagram for an IVHS network is presented. This block diagram defines the communications requirements for the IVHS network. The complete characterization of communication between the vehicle and the IVHS infrastructure is determined by the system architecture, however, by its very nature, this link is required to be wireless, mobile, and for the most part interactive. A survey of wireless technologies that have been tested, or implemented, and/or considered suitable for IVHS applications are discussed. Examples of operational and/or under development IVHS projects that applies the corresponding wireless technology are also provided.
Oxidative Dehydrogenation of Propane in the Realm of Metal–Organic Frameworks

Metal−organic framework-based catalytic formation of propene holds promise for low temperature sustainable production of this important feedstock.
Application of Modified Chebyshev Picard Iteration to Differential Correction for Improved Robustness and Computation Time

A novel application of Modified Chebyshev Picard Iteration (MCPI) to differential correction is presented. By leveraging the Chebyshev basis functions of MCPI, interpolation in 1 dimension may be used to target plane crossing events, instead of integrating the 42 dimensional variational equation required for standard step integrators. This results in dramatically improved performance over traditional differential correctors. MCPI was tested against the Runge-Kutta 7/8 integrator on over 45,000 halo orbits in three different three-body problems, and was found to be up to an order of magnitude faster, while simultaneously increasing robustness.
Low-Rank Approximation and Regression in Input Sparsity Time

We design a new distribution over m × n matrices S so that, for any fixed n × d matrix A of rank r, with probability at least 9/10, pSAxp2 = (1 ± e)pAxp2 simultaneously for all x ∈ Rd. Here, m is bounded by a polynomial in re− 1, and the parameter e ∈ (0, 1]. Such a matrix S is called a subspace embedding. Furthermore, SA can be computed in O(nnz(A)) time, where nnz(A) is the number of nonzero entries of A. This improves over all previous subspace embeddings, for which computing SA required at least Ω(ndlog d) time. We call these Ssparse embedding matrices.Using our sparse embedding matrices, we obtain the fastest known algorithms for overconstrained least-squares regression, low-rank approximation, approximating all leverage scores, and ep regression.More specifically, let b be an n × 1 vector, e > 0 a small enough value, and integers k, p g 1. Our results include the following.—Regression: The regression problem is to find d × 1 vector x′ for which pAx′ − bpp l (1 + e)min xpAx − bpp. For the Euclidean case p = 2, we obtain an algorithm running in O(nnz(A)) + O(d3e −2) time, and another in O(nnz(A)log(1/e)) + O(d3 log (1/e)) time. (Here, O(f) = f c log O(1)(f).) For p ∈ [1, ∞), more generally, we obtain an algorithm running in O(nnz(A) log n) + O(r\e −1)C time, for a fixed C.—Low-rank approximation: We give an algorithm to obtain a rank-k matrix Âk such that pA − ÂkpF ≤ (1 + e )p A − AkpF, where Ak is the best rank-k approximation to A. (That is, Ak is the output of principal components analysis, produced by a truncated singular value decomposition, useful for latent semantic indexing and many other statistical problems.) Our algorithm runs in O(nnz(A)) + O(nk2e−4 + k3e−5) time.—Leverage scores: We give an algorithm to estimate the leverage scores of A, up to a constant factor, in O(nnz(A)log n) + O(r3)time.
A Reconfigurable High-Performance Optical Data Center Architecture

Abstract-Optical data center network architectures are be- coming attractive because of their low energy consumption, large bandwidth, and low cabling complexity. In [1], an AWGR-based passive optical data center architecture (PODCA) is presented. Compared with other optical data center architectures, e.g., DOS [2], Proteus [3], and Petabit [4], PODCA can save up to 90% on power consumption and 88% in cost. Also, average latency can be low as 9 &#956;s at close to 100% throughput. However, PODCA is not reconfigurable and cannot optimize the network topology to dynamic traffic. In this paper, we present a novel, scalable and flexible recon- figurable architecture called RODCA. RODCA is built on and augments PODCA with a flexible localized intra-cluster optical network. With the reconfigurable intra-cluster network, racks with mutually large traffic can be located within the same cluster, and share the large bandwidth of the intra-cluster network. We present an algorithm for DCN topology reconfiguration, and present simulation results to demonstrate the effectiveness of reconfiguration.
Nanobubble induced formation of quantum emitters in monolayer semiconductors

The recent discovery of exciton quantum emitters in transition metal dichalcogenides (TMDCs) has triggered renewed interest of localized excitons in low-dimensional systems. Open questions remain about the microscopic origin previously attributed to dopants and/or defects as well as strain potentials. Here we show that the quantum emitters can be deliberately induced by nanobubble formation in WSe2 and BN/WSe2 heterostructures. Correlations of atomic-force microscope and hyperspectral photoluminescence images reveal that the origin of quantum emitters and trion disorder is extrinsic and related to 10 nm tall nanobubbles and 70 nm tall wrinkles, respectively. We further demonstrate that 'hot stamping' results in the absence of 0D quantum emitters and trion disorder. The demonstrated technique is useful for advances in nanolasers and deterministic formation of cavity-QED systems in monolayer materials.
Seq-Well: portable, low-cost RNA sequencing of single cells at high throughput

Seq-Well provides similar scale and data quality to massively parallel, droplet-based single-cell RNA-seq methods in an easy to use, inexpensive and portable microwell format compatible with low-input samples.
Assessing the accuracy of electricity demand forecasts in developing countries

This study assesses the accuracy of time-series econometric methods in forecasting electricity demand in developing countries. The analysis of historical time series for 106 developing countries over 1960-2012 demonstrates that econometric forecasts are highly accurate for the majority of these countries. These forecasts significantly outperform predictions of simple heuristic models, which assume that electricity demand grows at an exogenous rate or is proportional to real gross domestic product growth. The quality of the forecasts, however, diminishes for the countries and regions, where rapid economic and structural transformation or exposure to conflicts and environmental disasters makes it difficult to establish stable historical demand trends.
Developing Knowledge States: Technology and the Enhancement of National Statistical Capacity

National statistical systems are enterprises tasked with collecting, validating, and reporting societal attributes. These data serve many purposes—they allow governments to improve services, economic actors to traverse markets, and academics to assess social theories. National statistical systems vary in quality, especially in developing countries. This study examines determinants of national statistical capacity in developing countries, focusing on the impact of technological attainment. Just as technological progress helps to explain differences in economic growth, we argue that states with greater technological attainment have greater capacity for gathering and processing quality data. Analysis using panel methods shows a strong, statistically significant positive linear relationship between technological attainment and national statistical capacity.
A patch-based CBCT scatter artifact correction using prior CT

We have developed a novel patch-based cone beam CT (CBCT) artifact correction method based on prior CT images. First, we used the image registration to align the planning CT with the CBCT to reduce the geometry difference between the two images. Then, we brought the planning CT-based prior information into the Bayesian deconvolution framework to perform the CBCT scatter artifact correction based on patch-wise nonlocal mean strategy. We evaluated the proposed correction method using a Catphan phantom with multiple inserts based on contrast-to-noise ratios (CNR) and signal-to-noise ratios (SNR), and the image spatial non-uniformity (ISN). All values of CNR SNR and ISN in the corrected CBCT image were much closer to those in the planning CT images. The results demonstrated that the proposed CT-guided correction method could significantly reduce scatter artifacts and improve the image quality. This method has great potential to correct CBCT images allowing its use in adaptive radiotherapy.