cssi/SciSciGPT-SciSciNet huggingface dataset:
Market Power : Airports - Vertical Integration between Airports and Airlines

In the late 1980s and the 1990s many countries privatized airports or concessioned their operation. The United Kingdom began the trend, followed by other countries adopting new forms of infrastructure ownership and management. To control infrastructure licensing and the “natural monopoly” characteristics of some airport services, governments developed regulatory policies for airport systems. The operation of an airport creates incentives to transfer the airport’s market power to the air transport market. If the airport market is regulated but the airport operator is allowed to control at least one airline, those incentives can give rise to anticompetitive practices aimed at displacing competing airlines. When the regulatory framework for airports lacks explicit rules about such vertical integration, that can have consequences for competition in the air transport market. Australia and Chile, for example, have an explicit prohibition on vertical integration. By contrast, Argentina has no restrictions on vertical integration, leaving it to the antitrust agency to decide whether to approve or reject a vertical merger.
Simultaneous Inference of Cancer Pathways and Tumor Progression from Cross-Sectional Mutation Data

Abstract Recent cancer sequencing studies provide a wealth of somatic mutation data from a large number of patients. One of the most intriguing and challenging questions arising from this data is to determine whether the temporal order of somatic mutations in a cancer follows any common progression. Since we usually obtain only one sample from a patient, such inferences are commonly made from cross-sectional data from different patients. This analysis is complicated by the extensive variation in the somatic mutations across different patients, variation that is reduced by examining combinations of mutations in various pathways. Thus far, methods to reconstruct tumor progression at the pathway level have restricted attention to known, a priori defined pathways. In this work we show how to simultaneously infer pathways and the temporal order of their mutations from cross-sectional data, leveraging on the exclusivity property of driver mutations within a pathway. We define the pathway linear progression mode...
THE EQUITY CONSEQUENCES OF PUBLIC IRRIGATION INVESTMENTS: THE CASE OF SURFACE IRRIGATION SUBSIDIES IN INDIA

This paper is organized as follows. Section 1 reviews the structure of surface irrigation charges and the trends in irrigation expenditures and revenues in India. Section 2 discusses the measurement of irrigation subsidies and the data. Section 3 examines the incidence of surface irrigation subsidies and section 4 summarizes the magnitude of these sudsidies. Section 5 elaborates the policy implications of the findings of the study.
AMR Simulations of the Cosmological Light Cone: SZE Surveys of the Synthetic Universe

We present preliminary results from simulated large sky coverage ($∼100 square degrees) Sunyaev-Zeldovich effect (SZE) cluster surveys using the cosmological adaptive mesh inement N-body/hydro code Enzo. We have generated simulated light cones to match the resolution and sensitivity of current and future SZE instruments. These simulations are the most advanced calculations of their kind. The simulated sky surveys allow a direct comparison of large N-body/hydro cosmological simulations to current and pending sky surveys. Our synthetic surveys provide an indispensable guide for observers in the interpretation of large area sky surveys, and will develop the tools necessary to discriminate between models for cluster baryonic physics, and to accurately determine cosmological parameters.
Probabilistic latent semantic analysis

Probabilistic Latent Semantic Analysis is a novel statistical technique for the analysis of two-mode and co-occurrence data, which has applications in information retrieval and filtering, natural language processing, machine learning from text, and in related areas. Compared to standard Latent Semantic Analysis which stems from linear algebra and performs a Singular Value Decomposition of co-occurrence tables, the proposed method is based on a mixture decomposition derived from a latent class model. This results in a more principled approach which has a solid foundation in statistics. In order to avoid overfitting, we propose a widely applicable generalization of maximum likelihood model fitting by tempered EM. Our approach yields substantial and consistent improvements over Latent Semantic Analysis in a number of experiments.
The Physics of Cluster Mergers

Clusters of galaxies generally form by the gravitational merger of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. Some of the basic physical properties of mergers will be discussed, with an emphasis on simple analytic arguments rather than numerical simulations. Semi-analytic estimates of merger rates are reviewed, and a simple treatment of the kinematics of binary mergers is given. Mergers drive shocks into the intracluster medium, and these shocks heat the gas and should also accelerate nonthermal relativistic particles. X-ray observations of shocks can be used to determine the geometry and kinematics of the merger. Many clusters contain cooling flow cores; the hydrodynamical interactions of these cores with the hotter, less dense gas during mergers are discussed. As a result of particle acceleration in shocks, clusters of galaxies should contain very large populations of relativistic electrons and ions. Electrons with Lorentz factors γ∼300 (energies E=γm e c 2 ∼150 MeV) are expected to be particularly common. Observations and models for the radio, extreme ultraviolet, hard X-ray, and gamma-ray emission from nonthermal particles accelerated in these mergers are described.
Two-phase potential flow

Some features of two recent approaches of two-phase potential flow are presented. The first approach is based on a set of progressive examples that can be analyzed using common techniques, such as conservation laws, and taken together appear to lead in the direction of a general theory. The second approach is based on variational methods, a classical approach to conservative mechanical systems that has a respectable history of application to single phase flows. This latter approach, exemplified by several recent papers by Geurst, appears generally to be consistent with the former approach, at least in those cases for which it is possible to obtain comparable results. Each approach has a justifiable theoretical base and is self-consistent. Moreover, both approaches appear to give the right prediction for several well-defined situations.
LEARNING CAPABILITY, TECHNOLOGICAL PARITY, AND INNOVATION MODE USE

The purpose of this research was to examine whether a firm's learning capability interacts with industry technological parity to predict innovation mode use. Learning capability is conceptualized in the current research as a firm's ability to develop or acquire the new knowledge-based resources and skills needed to offer new products. Industry technological parity is conceptualized as the extent to which similarity and equality exist among the technological competencies of the firms in an industry. Three generic modes of innovation are considered: internal, cooperative, and external innovation. These modes reflect the development of new products based solely on internal resources, the collaborative development of new products (i.e., with one or more development partners), and the acquisition of fully developed products from external sources, respectively. The premises of this research are that (1) technological parity can create incentives or disincentives for innovating in a particular mode, depending upon the value of external innovative resources relative to the value of internal innovative resources and (2) firms will choose innovation modes that reflect a combination of their abilities and incentives to innovate alone, with others, or through others. Survey research and secondary sources were used to collect data from 119 high-technology firms. Results indicate that firms exhibit greater use of internal and external innovation when high levels of industry technological parity are matched by high levels of firm learning capability. By contrast, a negative relationship between learning capability and industry technological parity is associated with greater use of the cooperative mode of innovation. Thus, a single, common internal capability—learning capability—interacts with the level of technological parity in the environment to significantly predict three distinct innovation modes—modes that are not inherently dependent upon one another. As such, a firm's internal ability to innovate, as reflected in learning capability, has relevance well beyond that firm's likely internal innovation output. It also predicts the firm's likely use of cooperative and external innovation when considered in light of the level of industry technological parity. A practical implication of these findings is that companies with modest learning capabilities are not inherently precluded from innovating. Rather, they can innovate through modes for which conditions in their current environments do not constitute significant obstacles to innovation output. In particular, modest learning capabilities are associated with higher innovative output in the internal, cooperative, and external modes when industry technological parity levels are low, high, and low, respectively. Conversely, strong learning capabilities tend to be associated with higher innovative output in the internal, cooperative, and external modes when industry technological parity levels are high, low, and high, respectively.
Machine Descriptions to Build Tools for Embedded Systems

Because of poor tools, developing embedded systems can be unnecessarily hard. Machine descriptions based on register-transfer lists (RTLs) have proven useful in building retargetable compilers, but not in building other retargetable tools. Simulators, assemblers, linkers, debuggers, and profilers are built by hand if at all—previous machine descriptions have lacked the detail and precision needed to generate them. This paper presents detailed and precise machine-description techniques that are based on a new formalization of RTLs. Unlike previous notations, these RTLs have a detailed, unambiguous, and machine-independent semantics, which makes them ideal for supporting automatic generation of retargetable tools. The paper also gives examples of λ-RTL, a notation that makes it possible for human beings to read and write RTLs without becoming overwhelmed by machine-dependent detail.
Link between Mass-Loss and Variability Type for AGB Stars?

We discuss difficulties in explaining the distribution of AGB stars in the 25–12 vs. 12– K color–color diagram by steady-state radiatively driven models, and propose that the discrepancy may be due to changes of mass-loss rate with the time scales of ∼ 100 yr.
Eye-gaze determination of user intent at the computer interface

Abstract Determination of user intent at the computer interface through eye-gaze monitoring can significantly aid applications for the disabled, as well as telerobotics and process control interfaces. Whereas current eye-gaze control applications are limited to object selection and x/y gazepoint tracking, a methodology was developed here to discriminate a more Abstract interface operation: zooming-in or out. This methodology first collects samples of eye-gaze location looking at controlled stimuli, at 30 Hz, just prior to a user’s decision to zoom. The sample is broken into data frames, or temporal snapshots. Within a data frame, all spatial samples are connected into a minimum spanning tree, then clustered, according to user defined parameters. Each cluster is mapped to one in the prior data frame, and statistics are computed from each cluster. These characteristics include cluster size, position, and pupil size. A multiple discriminant analysis uses these statistics both within and between data frames to formulate optimal rules for assigning the observations into zoom-in, zoom- out, or no zoom conditions. The statistical procedure effectively generates heuristics for future assignments, based upon these variables. Future work will enhance the accuracy and precision of the modeling technique, and will empirically test users in controlled experiments.
A FAR-ULTRAVIOLET VIEW OF STARBURST GALAXIES

Recent observational and theoretical results on starburst galaxies related to the wavelength regime below 1200A are discussed. The review covers stars, dust, as well as hot and cold gas. This wavelength region follows trends similar to those seen at longer wavelengths, with several notable exceptions. Even the youngest stellar populations show a turn-over in their spectral energy distributions, and line-blanketing is much more pronounced. Furthermore, the OVI line allows one to probe gas at higher temperatures than possible with lines at longer wavelengths. Molecular hydrogen lines (if detected) provide a glimpse of the cold phase. I cover the crucial wavelength regime below 912A, and the implications of recent attempts to detect the escaping ionizing radiation.
Near‐Death Experiences

Near-death experiences (NDEs), profound events reported by people who have been close to death, often include feelings of peace, a sense of being outside the physical body, a life review, and meeting apparent nonphysical beings and environments; and they often precipitate profound changes in attitudes and values. Research on NDEs has focused on their epidemiology, psychophysiological correlates, and aftereffects, most commonly including increased spirituality, compassion, altruism, appreciation of life, and belief in postmortem existence. NDEs challenge the conventional assumption that consciousness is invariably linked to brain processes. Scientific discussions of the mind–brain problem must take these data into account.
Asymptotic Optimality of Constant-Order Policies for Lost Sales Inventory Models with Large Lead Times

Lost sales inventory models with large lead times, which arise in many practical settings, are notoriously difficult to optimize due to the curse of dimensionality. In this paper, we show that when lead times are large, a very simple constant-order policy, first studied by Reiman, performs nearly optimally. The main insight of our work is that when the lead time is very large, such a significant amount of randomness is injected into the system between when an order for more inventory is placed and when the order is received, that “being smart” algorithmically provides almost no benefit. Our main proof technique combines a novel coupling for suprema of random walks with arguments from queueing theory.
Elementary derivation of the expressions of momentum and energy in special relativity

The derivation of the expressions of momentum and energy of a particle in special relativity is often less than satisfactory in elementary texts. In some, it is obtained by resorting to quantum or electrodynamic considerations, in others by introducing non-elementary concepts, like that of a four-vector, or even misleading ones, like “relativistic mass”. Nevertheless it is possible, following ideas described by Einstein in 1935, to obtain a fully elementary derivation of these expressions based only on the Lorentz transformations, on the conservation laws, and on the Newtonian limit. The resulting argument allows for a clearer and logically consistent introduction to the basic concepts of relativistic dynamics.
Determining the number of signals by information theoretic criteria

The determination of the number of signals in a wide class of problems, including array processing, harmonic retrieval and pole retrieval, is addressed. A new approach, based on the application of the information theoretic criteria for model identification introduced by Akaike, Schwartz and Rissanen, is presented. It is shown that the criterion introduced by Schwartz and Rissanen yields a consistent estimate of the number of signals, while the criterion introduced by Akaike yields an inconsistent estimate that tends, in the large-sample limit, to overestimate the number of signals.
Synchronization of two passively mode-locked Er:doped fiber lasers using an acousto-optic modulator and grating design

Summary form only given. We synchronize two passively modelocked Er:doped fiber lasers of pulse width 4.5 ps by using a novel acousto-optic modulator and grating scheme. By measuring the cross-correlation of the two lasers, the interlaser jitter is extracted to be 1.3 times the pulse width. The temporal locking of lasers is important for telecommunication networks, measurement systems, and spectroscopy.
Gender-based violence in 140 characters or fewer: A #BigData case study of Twitter

Public institutions are increasingly reliant on data from social media sites to measure public attitude and provide timely public engagement. Such reliance includes the exploration of public views on important social issues such as gender-based violence (GBV). In this study, we examine big (social) data consisting of nearly 14 million tweets collected from Twitter over a period of 10 months to analyze public opinion regarding GBV, highlighting the nature of tweeting practices by geographical location and gender. We demonstrate the utility of computational social science to mine insight from the corpus while accounting for the influence of both transient events and sociocultural factors. We reveal public awareness regarding GBV tolerance and suggest opportunities for intervention and the measurement of intervention effectiveness assisting both governmental and non-governmental organizations in policy development.
Optimal control of one‐dimensional cellular uptake in tissue engineering

SUMMARY A control problem motivated by tissue engineering is formulated and solved, in which control of the uptake of growth factors (signaling molecules) is necessary to spatially and temporally regulate cellular processes for the desired growth or regeneration of a tissue. Four approaches are compared for determining one-dimensional optimal boundary control trajectories for a distributed parameter model with reaction, diffusion, and convection: (i) basis function expansion, (ii) method of moments, (iii) internal model control, and (iv) model predictive control (MPC). The proposed method of moments approach is computationally efficient while enforcing a nonnegativity constraint on the control input. Although more computationally expensive than methods (i)–(iii), the MPC formulation significantly reduced the computational cost compared with simultaneous optimization of the entire control trajectory. A comparison of the pros and cons of each of the four approaches suggests that an algorithm that combines multiple approaches is most promising for solving the optimal control problem for multiple spatial dimensions. Copyright © 2012 John Wiley & Sons, Ltd.
Observational Cosmology with the ELT and JWST

I will focus on the study of the Cosmic Dark ages and in particular on the properties of the galaxies responsible for the reionization of Hydrogen and on the possibility of detecting the first generation of galaxies and the first stars. I will make the case that there is a large and widening gap between our present and future capabilities in imaging and what we can follow-up spectroscopically even with the NIRSpec spectrograph on the James Webb Space Telescope because of its moderate field of view. A high throughput, high multiplexing near-IR spectrometer on the Extremely Large Telescope would be important to contain this gap. Studying the Lyman alpha forest of QSOs at z>=7 and measuring the kinematics of small mass galaxies at high-z are also problems unsuited to JWST and where a high-throughput, medium-high resolution near-IR spectrograph on the ELT would be essential.
Payments, credit and asset prices

This paper studies a modern monetary economy: trade in both goods and securities relies on money provided by intermediaries. While money is valued for its liquidity, its creation requires costly leverage. In ation, security prices and the transmission of monetary policy then depend on the institutional details of the payment system. The price of a security is higher if it helps back inside money, and lower if more inside money is used to trade it. In ation can be low in security market busts if bank portfolios suffer, but also in booms if trading absorbs more money. The government has multiple policy tools: in addition to the return on outside money, it affects the mix of securities used to back inside money.
Automatic Remodularization and Optimized Synthesis of Product-Families

A product-family is a suite of integrated tools that share a common infrastructure. Program synthesis of individual tools can replicate common code, leading to unnecessarily large executables and longer build times. In this paper, we present remodularization techniques that optimize the synthesis of product-families. We show how tools can be automatically remodularized so that shared files are identified and extracted into a common package, and how isomorphic class inheritance hierarchies can be merged into a single hierarchy. Doing so substantially reduces the cost of program synthesis, product-family build times, and executable sizes. We present a case study of a product-family with five tools totalling over 170K LOC, where our optimisations reduce archive size and build times by 40%.
Exact learning of RNA energy parameters from structure.

Abstract We consider the problem of exact learning of parameters of a linear RNA energy model from secondary structure data. A necessary and sufficient condition for learnability of parameters is derived, which is based on computing the convex hull of union of translated Newton polytopes of input sequences. The set of learned energy parameters is characterized as the convex cone generated by the normal vectors to those facets of the resulting polytope that are incident to the origin. In practice, the sufficient condition may not be satisfied by the entire training data set; hence, computing a maximal subset of training data for which the sufficient condition is satisfied is often desired. We show that the problem is NP-hard in general for an arbitrary dimensional feature space. Using a randomized greedy algorithm, we select a subset of RNA STRAND v2.0 database that satisfies the sufficient condition for separate A-U, C-G, G-U base pair counting model. The set of learned energy parameters includes experime...
Verification challenges and opportunities in the new era of microprocessor design

Microprocessor design continues to be driven by the economics of Moore's Law. Each new process generation doubles the number of transistors available to microprocessor architects and designers. Design complexity continues to increase, and so does verification complexity, in order to keep microprocessor performance scaling up with Moore's Law. Moving forward, we are facing even tougher challenges associated with the power scaling and reliability issues of future transistor devices. To build high performance, power efficient, reliable microprocessors using unreliable devices, we have to take a holistic approach, and deliver innovative technology solutions across the entire stack: circuit, micro-architecture, architecture, platform, and embedded software. Here we examine several future design trends and their implications on verification.
Gravitational signature of Jupiter's internal dynamics

Telescopic observations and space missions to Jupiter have provided vast information about Jupiter's cloud level winds, but the depth to which these winds penetrate has remained an ongoing mystery. Scheduled to be launched in 2011, the Jupiter orbiter Juno will make high-resolution observations of Jupiter's gravity field. In this paper we show that these measurements are sensitive to the depth of the internal winds. We use dynamical models ranging from an idealized thermal wind balance analysis, using the observed cloud-top winds, to a full general circulation model (GCM). We relate the depth of the dynamics to the external gravity spectrum for different internal wind structure scenarios. In particular, we predict that substantial Jovian winds below a depth of 500 km would lead to detectable (milligal-level) gravity anomalies with respect to the expected gravity for a planet in solid body rotation.
The second wave of independence : shopping for solutions

In the 21st century, many developing countries will become emerging markets and will no longer be in need of the carrot-and-stick approach to development assistance most prevalent today: development financing made available conditional on certain policies and interventions. This paper suggests that interactions between development agencies and recipient governments are mostly about inputs deemed (but not known) to contribute to improvements in living standards in recipient countries, rather than outcomes. The paper argues that the development marketplace is beset by market imperfections because of externalities, principal-agent problems, and decision making under uncertainty, which not only make it difficult to achieve the right outcomes, but also take away incentives to learn about outcomes. A fundamental rethink of responsibilities and accountabilities in the development business would make sure that development outcomes are traded in the development marketplace. It would put recipient countries in charge of contracting development agencies to provide these outcomes. Development agencies would commit to and be held financially accountable for outcomes, that is, real improvements in welfare indicators. The paper describes the role of the evaluation function in aligning incentives with the ultimate goal of improving lives and provides examples of emerging solutions.
Report on the Conference on Asian Economic History

A meeting of scholars to consider problems of teaching and research in Asian economic history was held in Highland Park, Illinois, October 30–31, 1959. It was organized under the auspices of The Research Center in Economic Development and Cultural Change of the University of Chicago, and funds were provided by the Division of Social Sciences of The Rockefeller Foundation. Professor Bert F. Hoselitz chaired the sessions.
Simulating Reading: Digital Research Beyond the Database

In the last decade, much digital humanities research involved databases. Digital technology allowed not only for expansion of concordances, but also, and more importantly, for new types of tagged, hyperlinked, and radiant texts. Databases changed the experience of reading. My research also involves a database, but I now realize that the consequence of building this peculiar database has led to what I believe is the next major aspect of research on the experience of reading: simulation. The reading machines on my website (www.readies.org) allude to Bob Carlton Brown’s machine proposed, in one iteration, in the late 1920s and early 1930s. He called the texts prepared for the machine “readies.” This project led to a realization that one could simulate reading situations and experiences usually only described. So, the Brown machine simulation becomes a prototype for a series of simulations on other reading situations both in the past and potential futures.
Benziporphyrins, a unique platform for exploring the aromatic characteristics of porphyrinoid systems

Benziporphyrins were first discovered over 20 years ago. Although initially they were considered to be a chemical curiosity, a wide range of benzene-containing porphyrinoid systems are now known that exhibit intriguing spectroscopic, structural and chemical properties. These systems can often generate stable organometallic derivatives, and have been shown to have applications in the development of chemical sensors and in molecular recognition studies. The characteristics of these porphyrinoid macrocycles vary from nonaromatic to highly aromatic systems, and in a few cases antiaromatic structures are formed. The variations in aromatic character are insightful and provide a deeper understanding of aromaticity and conjugation in porphyrinoid structures. In this review, the synthesis and properties of benziporphyrinoid systems is presented with a particular emphasis on the variations in aromatic characteristics.
Heavy Higgs bosons and the 2 TeV W′ boson

The hints from the LHC for the existence of a W ′ boson of mass around 1.9 TeV point towards a certain SU(2) L × SU(2) R × U(1) B−L gauge theory with an extended Higgs sector. We show that the decays of the W ′ boson into heavy Higgs bosons have sizable branching fractions. Interpreting the ATLAS excess events in the search for same-sign lepton pairs plus b jets as arising from W ′ cascade decays, we estimate that the masses of the heavy Higgs bosons are in the 400-700 GeV range.
Factors affecting human sperm penetration of zona-free hamster ova

Abstract The effects of in vivo and in vitro aging of hamster ova, protein supplementation of culture media, sperm concentration, and sperm motility on penetration of zona-free hamster ova by human sperm were investigated. Penetrability of ova was significantly lowered by 2 to 4 additional hours of in vivo aging or by an additional 3 hours of in vitro aging. A comparison was made of the effects of the addition to the media of human preovulatory serum and human serum albumin, and the penetrating ability of human sperm was increased with the addition of 10% human preovulatory serum. Sperm motility was also better maintained in the presence of 10% serum. Maximum penetration occurred after 3 hours of sperm-egg interaction following a 3-hour preincubation period with a sperm concentration of 5 × 10 6 motile sperm per milliliter. When motile sperm concentration was maintained at 1 × 10 7 motile sperm per milliliter, there was no correlation between penetrating ability and percentage of motility. These factors should be controlled to allow reproducible results with the hamster test.
A novel and direct synthesis of indoles via catalytic reductive annulation of nitroaromatics with alkynes

Indoles are produced regioselectively and in moderate yields from the reactions of nitroaromatics with alkynes catalyzed by [CpM(CO)2]2 (1; [(η5-C5H5)Fe(CO)2]2; [(η5-C5Me5)Fe(CO)2]2; [(η5-C5Me5)Ru(CO)2]2) under carbon monoxide.
Optimal Technology and Development

Abstract Skill intensive technologies seem to be adopted more often by rich countries rather than poor ones. Related to that observation, the ratio of wages of skilled to unskilled workers – the skill premium – shows two important features over time and across countries. In the US the skill premium decreased during the first half of the 20th century and increased after 1950, evolving in a U shaped pattern. On the other hand, the same measure across countries around 1990 is hump shaped when countries are ordered by GDP per worker. By modeling the decisions for factor accumulation and technology adoption, this paper gives a systematic explanation as to why we see ever more skill intensive technologies being adopted both over time in the US and across countries. The model developed here endogenously generates predictions for the skill premium that are consistent with both US and international observations under the same set of parameter values.
Keyword Search Advertising and Limited Budgets

In keyword search advertising, many advertisers operate on a limited budget. Yet how limited budgets affect keyword search advertising has not been extensively studied. This paper offers an analysis of the generalized second-price auction with budget constraints. We find that the budget constraint may induce advertisers to raise their bids to the highest possible amount for two different reasons, i.e., to accelerate the elimination of the budget-constrained competitor, and to reduce their own advertising cost. Thus, in contrast to the current literature, our analysis shows that both budget-constrained and unconstrained advertisers could bid more than their own valuation. We further extend the model to consider dynamic bidding and budget-setting decisions.
Women’s Theater and the Redefinitions of Public, Private, and Politics in North India

This essay explores the intersections between performance, materiality, and marginalized women’s struggles by delving into the meanings of public and private, and the nuanced and varied meanings of gendered resistance. Focusing on three very different kinds of theatrical performances by women in North India, I analyze how each performance appropriates, complicates, or reinforces the interwoven patriarchal concepts of public and private on the one hand, and femininity and masculinity on the other. In so doing, I also consider how both space and kinship are strategically deployed in these performances, and the different meanings of resistance and feminist politics embedded and implied in each performance. I argue that a focus on these processes allows us to grapple with the ways in which gendered materialities — shaped by class, caste, and geographical location — become central to the articulation of politics. This framework opens up new “spaces” to examine how multiple publics are constituted and reconfigured in terms of their socio- political identities and provisional alliances in and through publicization/privatization struggles, without essentializing or fixing the meanings of either public or private or of the spaces in which public/private acts are enacted.
Financial (dis-)information : evidence from an audit study in Mexico

An audit study was conducted in peri-urban Mexico to understand the quality of information and products offered to low-income potential customers. Trained auditors visited multiple financial institutions seeking credit and savings products. Consistent with Gabaix and Laibson (2006), staff voluntarily provides little information about avoidable fees, especially to auditors trained to reveal little knowledge about the market. In addition, clients are almost never offered the cheapest product, most likely because staff is incentivized to offer more expensive products that are thus more profitable to the institution. This suggests that disclosure and transparency policies may be ineffective if they undermine the commercial interest of financial institutions.
Wormhole and Entanglement (Non-)Detection in the ER=EPR Correspondence

The recently proposed ER=EPR correspondence postulates the existence of wormholes (Einstein-Rosen bridges) between entangled states (such as EPR pairs). Entanglement is famously known to be unobservable in quantum mechanics, in that there exists no observable (or, equivalently, projector) that can accurately pick out whether a generic state is entangled. Many features of the geometry of spacetime, however, are observables, so one might worry that the presence or absence of a wormhole could identify an entangled state in ER=EPR, violating quantum mechanics, specifically, the property of state-independence of observables. In this note, we establish that this cannot occur: there is no measurement in general relativity that unambiguously detects the presence of a generic wormhole geometry. This statement is the ER=EPR dual of the undetectability of entanglement.
EASTON'S THEOREM FOR RAMSEY AND STRONGLY RAMSEY CARDINALS

We show that, assuming GCH, if is a Ramsey or a strongly Ramsey cardinal and F is a class function on the regular cardinals having a closure point at and obeying the constraints of Easton's theorem, namely, F ( ) F ( ) for and < cf(F ( )), then there is a conality preserving forcing extension in which remains Ramsey or strongly Ramsey respectively and 2 = F ( ) for every regular cardinal .
Instability of superfluid flow in the neutron star inner crust

Pinning of superfluid vortices to the nuclear lattice of the inner crust of a neutron star supports a velocity difference between the superfluid and the solid as the star spins down. Under the Magnus force that arises on the vortex lattice, vortices undergo vortex creep through thermal activation or quantum tunnelling. We examine the hydrodynamic stability of this situation. Vortex creep introduces two low-frequency modes, one of which is unstable above a critical wavenumber for any non-zero flow velocity of the superfluid with respect to the solid. For typical pinning parameters of the inner crust, the superfluid flow is unstable over length scales ≲10 m and over time-scales as fast as months. The vortex lattice could degenerate into a tangle, and the superfluid flow could become turbulent. Unexpectedly large dissipation would suppress this instability.
Rush to Judgment: The STI-Treatment Trials and HIV in Sub-Saharan Africa

Introduction : The extraordinarily high incidence of HIV in sub-Saharan Africa led to the search for cofactor infections that could explain the high rates of transmission in the region. Genital inflammation and lesions caused by sexually transmitted infections (STIs) were a probable mechanism, and numerous observational studies indicated several STI cofactors. Nine out of the ten randomized controlled trials (RCTs), however, failed to demonstrate that treating STIs could lower HIV incidence. We evaluate all 10 trials to determine if their design permits the conclusion, widely believed, that STI treatment is ineffective in reducing HIV incidence. Discussion : Examination of the trials reveals critical methodological problems sufficient to account for statistically insignificant outcomes in nine of the ten trials. Shortcomings of the trials include weak exposure contrast, confounding, non-differential misclassification, contamination and effect modification, all of which consistently bias the results toward the null. In any future STI-HIV trial, ethical considerations will again require weak exposure contrast. The complexity posed by HIV transmission in the genital microbial environment means that any future STI-HIV trial will face confounding, non-differential misclassification and effect modification. As a result, it is unlikely that additional trials would be able to answer the question of whether STI control reduces HIV incidence. Conclusions : Shortcomings in published RCTs render invalid the conclusion that treating STIs and other cofactor infections is ineffective in HIV prevention. Meta-analyses of observational studies conclude that STIs can raise HIV transmission efficiency two- to fourfold. Health policy is always implemented under uncertainty. Given the known benefits of STI control, the irreparable harm from not treating STIs and the likely decline in HIV incidence resulting from STI control, it is appropriate to expand STI control programmes and to use funds earmarked for HIV prevention to finance those programmes. Keywords: HIV; AIDS; RCT; STI; sub-Saharan Africa; sexually transmitted disease and HIV; randomized controlled trial. (Published: 18 May 2015) Citation: Stillwaggon E and Sawers L. Journal of the International AIDS Society 2015, 18 :19844 http://www.jiasociety.org/index.php/jias/article/view/19844 | http://dx.doi.org/10.7448/IAS.18.1.19844
Design of Sparse Filters for Channel Shortening

Channel shortening equalizers are used in acoustics to reduce reverberation, in error control decoding to reduce complexity, and in communication receivers to reduce inter-symbol interference. The cascade of a channel and channel shortening equalizer ideally produces an overall impulse response that has most of its energy compacted into fewer adjacent samples. Once designed, channel shortening equalizers filter the received signal on a per-sample basis and need to be adapted or re-designed if the channel impulse response changes significantly. In this paper, we evaluate sparse filters as channel shortening equalizers. Unlike conventional dense filters, sparse filters have a small number of non-contiguous non-zero coefficients. Our contributions include (1) proposing optimal and sub-optimal low complexity algorithms for sparse shortening filter design, and (2) evaluating impulse response energy compaction vs. design and implementation stage computational complexity tradeoffs for the proposed algorithms. We apply the proposed equalizer design procedures to (1) asymmetric digital subscriber line channels and (2) underwater acoustic communication channels. Our simulation results utilize measured channel impulse responses and show that sparse filters are able to achieve the same channel energy compaction with half as many coefficients as dense filters.
Line Asymmetry of Solar p-Modes: Reversal of Asymmetry in Intensity Power Spectra

The sense of line asymmetry of solar p-modes in the intensity power spectra is observed to be opposite of that seen in the velocity power spectra. Theoretical calculations provide a good understanding and fit to the observed velocity power spectra, whereas the reverse sense of asymmetry in the intensity power spectrum has been poorly understood. We show that when turbulent eddies arrive at the top of the convection zone they give rise to an observable intensity fluctuation that is correlated with the oscillation they generate, thereby affecting the shape of the line in the p-mode power spectra and reversing the sense of asymmetry (this point was recognized by Nigam et al. and Roxburgh & Vorontsov). The addition of the correlated noise displaces the frequencies of peaks in the power spectrum. Depending on the amplitude of the noise source, the shift in the position of the peak can be substantially larger than the frequency shift in the velocity power spectra. In neither case are the peak frequencies precisely equal to the eigenfrequencies of p-modes. We suggest two observations that can provide a test of the model discussed here.
The social contagion hypothesis: comment on ‘Social contagion theory: examining dynamic social networks and human behavior’

I reflect on the statistical methods of the Christakis–Fowler studies on network-based contagion of traits by checking the sensitivity of these kinds of results to various alternate specifications and generative mechanisms. Despite the honest efforts of all involved, I remain pessimistic about establishing whether binary health outcomes or product adoptions are contagious if the evidence comes from simultaneously observed data. Copyright © 2012 John Wiley & Sons, Ltd.
A database for designing large physical systems

To date, paper and pencil have been the principal medium for problem-solving and communication in architecture and engineering. While the computer has helped analyze topological and 2-dimensional problems, the drawingboard has remained the principal problem-solving tool for complex 3-dimensional systems.
On the Whitham Equations for the Defocusing Nonlinear Schrodinger Equation with Step Initial Data

The behavior of solutions of the finite-genus Whitham equations for the weak dispersion limit of the defocusing nonlinear Schrodinger equation is investigated analytically and numerically for piecewise-constant initial data. In particular, the dynamics of constant-amplitude initial conditions with one or more frequency jumps (i.e., piecewise linear phase) are considered. It is shown analytically and numerically that, for finite times, regions of arbitrarily high genus can be produced; asymptotically with time, however, the solution can be divided into expanding regions which are either of genus-zero, genus-one, or genus-two type, their precise arrangement depending on the specifics of the initial datum given. This behavior should be compared to that of the Korteweg-de Vries equation, where the solution is divided into regions which are either genus-zero or genus-one asymptotically. Finally, the potential application of these results to the generation of short optical pulses is discussed: The method proposed takes advantage of nonlinear compression via appropriate frequency modulation, and allows control of both the pulse amplitude and its width, as well as the distance along the fiber at which the pulse is produced.
Advances in the surgical management of bone tumors

Bone tumor surgery is extremely challenging, particularly when tumors are located in tightly confined anatomical areas and abutting critical organs and neurovascular structures. Tumor resection requires good cutting accuracy to ensure safety, to achieve negative margins, and to preserve critical structures when possible. The purpose of this paper was to review the literature on the surgical advances for bone tumor surgery published within the last year. The majority of literature identified focused on computer-assisted surgical approaches. There is increasing evidence that 3D navigation plays an important role in the resection of bone tumors. Reconstruction materials that encourage healing and prevent infections are also in development. Optimal care includes execution of a well-developed pre-operative plan using a multidisciplinary approach led by the orthopaedic oncologist.
Enantioselective syntheses of (+)- and (−)-Phaseolinic acid

Abstract (+)- and (−)-Phaseolinic acid ( 1 ) have been prepared in an enantioselective fashion from acetylenic acid 26 (or ent- 26 ) by a three step sequence involving lactonization, epimerization at C 3 , and oxidative cleavage. 26 was obtained as a single enantiomer using a Nicholas-Schreiber reaction.
Approximate Aggregation under Uncertainty

Abstract For a collection of agents with von Neumann-Morgenstern preferences, a price-independent income distribution, and identical probability beliefs, there exists a von Neumann-Morgenstern approximate aggregator. The risk tolerance of the approximate aggregator is equal to the sum of the individual agent risk tolerances at prices which yield constant, “risk-free”, contingent consumption. The application of the approximate aggregator to standard asset pricing models in finance is discussed briefly.
Decentralized erasure codes for distributed networked storage

In this correspondence, we consider the problem of constructing an erasure code for storage over a network when the data sources are distributed. Specifically, we assume that there are n storage nodes with limited memory and k n sources generating the data. We want a data collector, who can appear anywhere in the network, to query any k storage nodes and be able to retrieve the data. We introduce decentralized erasure codes, which are linear codes with a specific randomized structure inspired by network coding on random bipartite graphs. We show that decentralized erasure codes are optimally sparse, and lead to reduced communication, storage and computation cost over random linear coding.
Net two-beam-coupling gain in a polymeric photorefractive material.

Two-beam-coupling gain coefficients exceeding the absorption coefficient are demonstrated for the first time to our knowledge in an organic photorefractive system. The material is based on the photoconducting polymer poly(N-vinylcarbazole), doped with the optically nonlinear chromophore 3-fluoro-4-N,N-diethylamino-β-nitrostyrene and sensitized for charge generation with 2,4,7-trinitro-9-fluorenone. The photorefractive performance is significantly better than that of any previously described organic. Diffraction efficiencies as large as 1% in a 125-μm sample, grating growth times of the order of 100 ms, and beam-coupling gain coefficients >10 cm−1 were observed at 647 nm (writing intensity of 1 W cm−2, applied field of 40 V μm−1).