cssi/SciSciGPT-SciSciNet huggingface dataset:
The Paradox of Ideology

Marx's social theory seems to involve a sharp case of a well-known paradox in sociology of knowledge. The puzzle arises when we discover on the basis of scientific inquiry that belief in scientific claims is produced and maintained by noncognitive social interest or positions. The worry is that belief so produced is for that reason suspect. A cognitive interest is an intrinsic interest in the truth or warrant, or more broadly in the epistemic properties, of some claim or belief. But according to Marx's theory of ideology,
A note on the theory of demand-led growth

this paper presents a demand-led growth model where an exogenous investment function drives capital accumulation through a Bernoulli differential equation. In such framework investment generates savings through changes in capacity utilization and/or income distribution, making economic growth totally demand-led. Taking a Structuralist perspective, the model is purposefully made to be consistent with different Keynesian closures for the investment function, as well as with different assumptions about savings’ adjustment to investment.
State-Level Carbon Taxes and the Dormant Commerce Clause: Can Formulary Apportionment Save the World?

A carbon price is coming, or so it would seem. Even though in the United States there have only been a handful of successful state-level efforts,1 large firms are assuming that a price will be placed on their greenhouse gas emissions.2 Yet until recently, it was unclear as a practical matter how a national price for carbon was going to get established.3 Indeed, it is still unclear, but one possible avenue has opened up. This is because in June 2014, the Environment Protection Agency (“EPA”) released draft rules mandating significant reduction in the release of carbon, a greenhouse gas. Specifically, by 2030 these rules aim to “achieve CO2 emission reductions from the power sector of approximately 30 percent from CO2 emission levels in 2005.” These rules give states great flexibility in achieving the required reductions.5
Are corporate inversions good for shareholders

Abstract Corporate inversion, the process of redomiciling for tax purposes, reduces corporate income taxes, but it imposes a personal tax cost that is shareholder-specific. We develop a model, incorporating the corporate tax benefits and personal tax costs, to quantify the return to inversion for different shareholders. Foreign and tax-exempt investors, along with the chief executive officer, disproportionately benefit. We show that an inversion simultaneously reduces the wealth of many taxable shareholders. The model illustrates an agency conflict in which heterogeneity in personal taxes generates a wealth transfer between shareholders. Furthermore, personal taxes offset the loss in government revenue by 39%.
TRUE WORLD INCOME DISTRIBUTION, 1988 AND 1993: FIRST CALCULATION BASED ON HOUSEHOLD SURVEYS ALONE

The paper derives world income or expenditure distribution of individuals for two years 1988 and 1993. It is the first paper to calculate world distribution for individuals based entirely on household survey data from 91 countries, and adjusted for differences in purchasing power parity between the countries. Measured by the Gini index, inequality increased from an already very high 63 in 1988 to 66 in 1993. The increase was driven more by rising differences in mean incomes between the countries than by rising inequalities within countries. The most important contributors were rising urban-rural differences in China, and slow growth of rural incomes in South Asia compared to several large developed market economies.
CEO compensation, director compensation, and firm performance: Evidence of cronyism?

Abstract We model CEO and director compensation using firm characteristics, CEO characteristics, and governance variables. After controlling for monitoring proxies, we find a significant positive relationship between CEO and director compensation. We hypothesize that this relationship could be due to unobserved firm complexity (omitted variables), and/or to excess compensation of directors and managers. We also find evidence that excess compensation (both director and CEO) is associated with firm underperformance. We therefore conclude that the evidence is consistent with excessive compensation due to mutual back scratching or cronyism. The evidence suggests that excessive compensation has an effect on firm performance that is independent of the poor governance variables discussed by previous studies.
Public radio in the United States: does it correct market failure or cannibalize commercial stations?

Because broadcasters can capture only part of the value of their product as revenue, there is the potential for a classic problem of underprovision. Whether public support corrects a market failure depends on whether the market would have provided similar services in the absence of public broadcasting. We address these questions by asking whether public and commercial classical stations compete for listening share and revenue as well as whether public stations crowd out commercial stations. We find evidence that public broadcasting crowds out commercial programming in large markets, particularly in classical music and to a lesser extent in jazz. © 1999 Elsevier Science S.A. All rights reserved.
The Moderating Role of Product Categories in the Relationship between Online Fulfillment, Procurement, and Consumer Repurchase Intention: A Hierarchical Analysis

This study investigates how the number of product categories moderates the effects of consumers' satisfaction with order procurement and order fulfillment on their repurchase intention at online retail stores. We collected empirical data from an online rating website and constructed a multilevel dataset at both the transaction level and the store level. Employing hierarchical linear modeling on a sample of 11,554 observations at 146 online retailers, we find significant interaction effects on consumer repurchase intention between product category number and consumer satisfaction with both online order procurement and fulfillment processes, but with different signs. These findings offer guidance to online retailers when allocating their limited resources to procurement-related and fulfillment-related investments.
Estimating the Elasticity of Intertemporal Substitution When Instruments Are Weak

In the instrumental variables (IV) regression model, weak instruments can lead to bias in estimators and size distortion in hypothesis tests. This paper examines how weak instruments affect the identification of the elasticity of intertemporal substitution (EIS) through the linearized Euler equation. Conventional IV methods result in an empirical puzzle that the EIS is significantly less than 1 but its reciprocal is not different from 1. This paper shows that weak instruments can explain the puzzle and reports valid confidence intervals for the EIS using pivotal statistics. The EIS is less than 1 and not significantly different from 0 for eleven developed countries.
Radio‐loud CMEs from the disk center lacking shocks at 1 AU

A coronal mass ejection (CME) associated with a type II burst and originating close to the center of the solar disk typically results in a shock at Earth in 2-3 days and hence can be used to predict shock arrival at Earth. However, a significant fraction (about 28%) of such CMEs producing type II bursts were not associated with shocks at Earth. We examined a set of 21 type II bursts observed by the Wind/WAVES experiment at decameter-hectometric (DH) wavelengths that had CME sources very close to the disk center (within a central meridian distance of 30 degrees), but did not have a shock at Earth. We find that the near-Sun speeds of these CMEs average to ~644 km/s, only slightly higher than the average speed of CMEs associated with radio-quiet shocks. However, the fraction of halo CMEs is only ~30%, compared to 54% for the radio-quiet shocks and 91% for all radio-loud shocks. We conclude that the disk-center radio-loud CMEs with no shocks at 1 AU are generally of lower energy and they drive shocks only close to the Sun and dissipate before arriving at Earth. There is also evidence for other possible processes that lead to the lack of shock at 1 AU: (i) overtaking CME shocks merge and one observes a single shock at Earth, and (ii) deflection by nearby coronal holes can push the shocks away from the Sun-Earth line, such that Earth misses these shocks. The probability of observing a shock at 1 AU increases rapidly above 60% when the CME speed exceeds 1000 km/s and when the type II bursts propagate to frequencies below 1 MHz.
Knowledge management technology as a stage for strategic self-presentation: Implications for knowledge sharing in organizations

This article explores why it is often difficult for organizations to capture, store, and share employees' individually held expertise. Drawing on studies of the social construction of expertise and theories of transactive memory systems and self-presentation in computer-mediated environments, we argue that knowledge management technologies are not simple containers for the storage of expertise, but that they are stages upon which individuals enact performances of expertise. Through a longitudinal study of the work of IT technicians we show that users of a knowledge management technology strategically craft their own information entries to position themselves as experts vis-a-vis their coworkers. The data suggest that proactive self-presentations enacted by a few actors early on may spur reactive behaviors of strategic self-presentation across the organization. We explore implications of these findings for theories of transactive memory systems and technology use in organizations.
Brand Management and Strategies Against Counterfeits

In this paper, I provide a theory for brand-protection strategies to reduce counterfeiting under weak intellectual property rights. My theoretical framework has general implications for endogenous sunk cost investments as a means of deterring counterfeiters. My model incorporates two layers of asymmetric information that counterfeits can incur: counterfeiters fooling consumers and buyers of counterfeits fooling other consumers. Brands have a number of tools at their disposal to maintain a separating equilibrium in the face of counterfeits. One of the theoretical predictions of this study is that counterfeit entry induces incumbent brands to introduce new products. This helps to explain the innovation strategies that authentic firms employ in response to entry by counterfeiters in practice. Authentic prices rise if and only if the counterfeit quality is lower than a threshold level. In addition, the model demonstrates how authentic producers could invest in self-enforcement to increase counterfeiters' incentives to separate themselves from brands. Better channel management through company stores and other costly devices are forms of nonprice signals and complement a company's own enforcements against counterfeits. These predictions are validated using unique panel data collected from Chinese shoe companies covering the years 1993�2004. Data further reveal that companies with worse relationships with the government invest more in various self-enforcement strategies, which are effective in reducing counterfeit sales, and that the set of strategies are complements rather than substitutes for each other.
Testing the Potential of RFID to Increase Supply-Chain Agility and to Mitigate the Bullwhip Effect

This study examines the potential of RFID technology to increase the agility of supply-chain e-commerce systems by mitigating the bullwhip effect. The bullwhip effect is a supply-chain phenomenon that reveals a lack of business agility characterized by the amplification of inventory variance. This study employs an experiment involving a modified Beer Distribution Game to simulate an RFID-enabled supply chain. The results provide empirical evidence that RFID technology can increase a supply chainâ€™s agility and reduce the bullwhip effect by reducing inventory holding costs, stock out costs, and inventory-level variances. The results are all the more important when applied to interorganizational e-commerce systems.
Reporting errors, ability heterogeneity, and returns to schooling in China

. This study is aimed at providing a more accurate estimate of the returns to schooling in China by controlling for unobserved ability heterogeneity and measurement errors. We identify a unique instrument to correct for the omitted ability bias. We find that the attenuation bias caused by measurement error dominates the omitted ability bias in the OLS estimation. Based on the GMM estimation, for young workers in China, the return to schooling is 15.0% overall and 16.9% for women.
Regulation By Exemption: the Changing Definition of an Accredited Investor

The Securities and Exchange Commission ("SEC") has preserved its jurisdictional grip and ideological purity with respect to the regulation of initial public offerings and the regulation of mutual funds by creating huge exemptions from its regulatory scheme. While these exemptions have been in response to push backs against a rigid and complex framework for the registration of public offerings and the governance of mutual funds, it has led to anomalies in the capital markets, arguably not in the interests of the retail investors the SEC endeavors to protect. The SEC exemptions have been achieved through the use of the "accredited investor" concept, injected into the Securities Act of 1933 ("Securities Act") in 1980. The problem with regulating by exemption is that it does not incentivize the SEC to adjust regulations that discourage capital market participants from entering a regulated system. Instead of reforming the registration provisions of the Securities Act to make such registration more user friendly and less likely to result in after-the-fact lawsuits, the SEC fashioned private placement exemptions that have created a huge market for unregistered offerings. Instead of trying to reform the Investment Company Act and the Advisers Act to accommodate hedge funds and private equity funds, the SEC exempted them for many years, and then, becoming worried that a large part of the capital market had moved beyond its jurisdiction, unsuccessfully tried to recapture jurisdiction over these investment pools.
Public pension accounting rules and economic outcomes

We find a negative association between a state׳s fiscal condition and the use of discretion in applying Governmental Accounting Standards Board (GASB) rules to understate pension funding gaps. We also find that the use of discretion is negatively associated with states’ decisions to increase taxes and cut spending. In addition, we find that the funding gap understatement is positively associated with higher future labor costs. Importantly, this association is primarily attributable to the GASB methodology, which systematically understates the funding gap. This suggests that the GASB approach is associated with policy choices that have the potential to exacerbate fiscal stress.
Government Intervention and Arbitrage

Direct government intervention in a market may induce violations of the law of one price in other, arbitrage-related markets. I show that a government pursuing a nonpublic, partially informative price target in a model of strategic market-order trading and segmented dealership generates equilibrium price differentials among fundamentally identical assets by clouding dealers’ inference about the targeted asset’s payoff from its order flow, to an extent complexly dependent on existing price formation. I find supportive evidence using a sample of American Depositary Receipts and other cross-listings traded in the major U.S. exchanges, along with currency interventions by developed and emerging countries between 1980 and 2009. Received May 18, 2016; editorial decision May 10, 2017 by Editor Andrew Karolyi.
An Approximation Algorithm for Optimal Consumption/Investment Problems

This article develops a simple approach to solving continuous-time portfolio choice problems. Portfolio problems for which no closed-form solutions are available may be handled by this technique, which substitutes the numerical solution of partial differential equations with a non-linear numerical algorithm approximating the solution. This paper complements the wide literature in economics on the solution of dynamic problems in discrete time using projection methods. Our approach extends the approximation function to power forms, which are shown to fit finance type problems well. The algorithm is parsimonious, and is first illustrated by solving two basic examples, first, the standard Merton problem, and second, a jump-diffusion problem. Then, we demonstrate that the model is easy to implement on a larger scale, by optimizing a portfolio of six stock indexes, and stochastic volatility driven by two correlated state variables. Copyright © 2002 John Wiley & Sons, Ltd.
Two's Company, Three's a Crowd? Triads in Cooperative-Competitive Networks

Triadic structure is an important, but neglected, aspect of interfirm networks. We developed the constructs clustering and countering as potential drivers of triadic structure and combined them wit...
The Bill of Rights in the Early State Courts

I. Barron Revisited 7 A. John Barron’s Wharf 8 B. The Court of Appeals and the Fifth Amendment .... 11 C. The Supreme Court’s Decision 14 D. Barron Reconsidered 16 E. One-Way Review 18 II. State Courts and the Federal Bill of Rights 23 A. Overview 23 B. Textual Support 26 C. Applications of the Bill of Rights 32 1. Second Amendment 32 2. Fourth Amendment 35 3. Fifth Amendment—Takings 37 4. Fifth Amendment—Double Jeopardy 43 5. Fifth Amendment—Due Process and Self-Incrimination 47 6. Sixth Amendment 48 7. First and Seventh Amendments 52 8. The Broader Influence of the Bill of Rights ....... 53 D. Summary 55 III. Bodies of Constitutional Law 55 A. Overview 55 B. Federal and State Constitutions 56 C. General Constitutional Law 59
Private Standardization in Public International Lawmaking

Introduction 481 I. The Path Toward an ISO Standard on Social Responsibility 483 II. The Decision to Develop an ISO Standard on Social Responsibility 486 III. The Process of Developing ISO 26000 490 A. Question of Representativity 492 B. Operational Issues 495 1. Operating Structures 495 2. Operating Procedures 497 3. Operational Role of Public International Organizations 499 4. Meaningful Participation: Foreign Languages 503 C. Search for Normative Coherence 504 D. Search for Postpublication Continuity 512 IV. Legal and Policy Context for International Standards Relating to Public Policy 515 V. ISO Exercise in the Legal Context 523 VI. Proposals for a Legally Sustainable Framework 528 Conclusion and Next Steps: Coordination and a Protocol of Good Practice for Standardization in Fields Related to Public Policy ......... 534
Lessons of the crisis for emerging markets

This paper analyzes the impact of the global financial crisis on emerging markets. It argues that the crisis will have enduring implications for policy toward the development and liberalization of financial markets. In particular, emerging markets will rely (even) less on external finance and adopt a less permissive approach to foreign bank presence. In contrast, the crisis will have a much more limited impact on other aspects of globalization. More controversially, the paper argues that the crisis is unlikely to have a major impact on the structure of the international monetary system.
Privacy, Power, and Humiliation at Work: Re-Examining Appearance Regulation as an Invasion of Privacy

Workplace rules that deny fundamental aspects of personal autonomy are (in many states) and should be actionable invasions of privacy. Perhaps nowhere is the invasion more keenly felt than when an employer demands, under penalty of forfeiting one's livelihood, that one dress or alter one's physical appearance in a way that one finds offensive, degrading, inappropriate, or alien. Clothes and appearance are constitutive of how we see and feel about ourselves and how we construct ourselves for the rest of the world to see. Conventions of appearance for women and men, for racial, ethnic, and religious groups express and observe political and spiritual commitments that affect people at a deep psychological level. In this essay, I argue that the legal framework of autonomy privacy is a necessary supplement to the discrimination analysis that has dominated legal thinking for thirty-five years of challenges to workplace appearance requirements. Some appearance requirements should be legally suspect even when they do not discriminate on the basis of a protected status. A privacy analysis, in contrast to a discrimination analysis, is a legal theory that is available to anyone who is significantly oppressed by an unreasonable workplace dress code. Privacy analysis may thus be more resistant to charges of special treatment and the backlash that such charges can generate. From the employer's standpoint, privacy analysis allows more flexibility and nuance in distinguishing appearance regulations that are legal from those that are not. It might, for example, preserve the ability of an employer to require some dress conventions, including some that may reflect gender, religious, and other norms, while ruling out others. A privacy analysis would help courts distinguish between dress codes that humiliate and those that do not, as well as help a court understand that a dress code can be generally valid but cannot be enforced against a particular employee who might find a particular dress requirement exceptionally humiliating or offensive. Wholly apart from the effects of a privacy analysis on the outcome of litigation, I think it will also prompt a more thoughtful analysis by firms of whether or how they should attempt formally to regulate employee appearance and how to handle the employee who objects. A privacy analysis will prompt an employer to consider the strength of its justification for its policy, the degree of humiliation it will cause particular workers, and whether the harm is necessary to achieve the benefit. A discrimination analysis, by contrast, invites an employer to adopt even a silly appearance regulation (e.g., women must wear make-up and nail polish) if the employer can convince itself that the regulation is not sex discrimination because it equally burdens men or because only certain women will object. Privacy analysis will thus better identify and accommodate the employer's interest in the appearance of its workforce with interests of various employees in being free from humiliating workplace requirements.
Describing the Ball: Improve Teaching by Using Rubrics - Explicit Grading Criteria

Assessment is crucial to effective teaching and learning. Carnegie's Educating Lawyers and Roy Stuckey's Best Practices for Legal Education emphasize the importance of assessment. This article explains how detailed, written grading criteria describing what students should learn and how they will be evaluated should be a central part of law teachers' assessment plans. The article details how rubrics can improve law student learning, and contains both detailed, step-by-step directions on creating rubrics and examples of rubrics from many different law school courses.
Opaque banks, price discovery, and financial instability

Abstract Opacity fosters price contagion that exacerbates the speculative cycles of bubbles and crashes that create financial instability. We find that banks with larger investments in opaque assets benefitted more from intra-industry revaluations associated with announcements of mergers in the period 2000–2006. The findings are robust to controls for competitive effects, spillover effects from higher likelihood of takeover, changes in real estate prices, and interest rates. Non-merger banks that gained most from merger activities also experienced the largest price declines during the subsequent 2007–2008 financial crisis.
Market Mechanism Choice and Real Estate Disposition: Search Versus Auction

We propose a model of mechanism choice in the disposition of real estate assets where we consider two alternatives: a search market and an auction. Within the search framework, we derive an equilibrium whereby buyers incur search costs and sellers incur holding costs for the period during which the property is not sold. In the auction alternative, the seller joins an existing pool of sellers in undertaking a multiple–object auction and pays a commission upon sale. Buyers and sellers freely choose their mechanisms, which in equilibrium are optimal given each group’s conjectures about the mechanism choice of their counterpart. In equilibrium, an agent cannot benefit from deviating from his choice and each agent’s beliefs are consistent with the equilibrium outcome. It is shown that (a) buyers with high search costs will choose auctions because the auction payoff imposes an upper bound on buyers' gains from search, and (b) prices at auctions will be higher. Using vacant lot sales data and a method–of–moment estimator which accounts for the presence of an endogenous discrete mechanism choice variable, we estimated a hedonic regression to detect the price effect. It was determined that, on average, lots sold for $1.44 per square foot more in auctions than in the search market, as predicted by our model.
Does corporate diversification exacerbate or mitigate earnings management?: An empirical analysis

Abstract The purpose of this study is to determine whether earning management is exacerbated or alleviated in diversified firms. An explicit distinction is made between industrial and geographic diversification. The empirical evidence shows that earnings management is mitigated by 1.8% in industrially diversified firms. The evidence also shows that a combination of industrial and global diversification helps alleviate earnings management by 2.5%. Global diversification alone, however, does not appear to impact earnings management. We argue that diversified firms derive their cash flows from disparate business divisions. The accruals generated by these business divisions are imperfectly correlated and, hence, tend to offset each other at the entire firm's level, making it difficult for managers to manage earnings considerably in either direction. Finally, our results show that diversified firms do not suffer more severe informational asymmetry, which may explain why earnings management does not occur to a greater extent in diversified firms.
Implications of a Multi-Purpose Reporting System on CEO and CFO Incentives and Risk Preferences

ABSTRACT This paper presents a model in which the CEO generates productive output while the CFO oversees a reporting system that provides information useful for monitoring, decision-making, and contracting, but is also subject to costly manipulation. Because the reporting system serves multiple roles, the CEO's compensation incentives and the quality of the reporting system can be substitutes or complements. When they are substitutes, the CEO's incentive compensation is positively related to performance metric risk, firm value can be increasing in the CFO's risk aversion, and high biasing costs can reduce the positive association between firm value and CFO risk aversion. Whether they are primarily substitutes or complements can depend on the speed of decreasing returns to scale in the production function. The potential value of CEO-CFO collusion in this setting is explored in an extension.
Linguistics and Claim Construction

Despite its great importance in patent litigation and recent interest derived from the U.S. Court of Appeals for the Federal Circuit's en banc Phillips opinion, claim construction - the process of giving a patent claim meaning through defining its terms - is largely an unsettled and uncertain area of patent law. In part, this uncertainty may be due to the Federal Circuit's failure to provide adequate guidance on the process. This Article suggests that the Federal Circuit should clarify its claim construction jurisprudence, looking to the science of linguistics to provide bases for an improved set of guidelines that will improve certainty in patent law. This Article argues that claim construction should instead track the way in which we, as readers of a language, attempt to understand what is being conveyed via the written word. First, there is a base level of conventional understanding from which all interpretation starts, an understanding that either a priori exists based on our earlier encounters with the word or is obtained from a dictionary in cases where we lack previous knowledge. Second, from this conventional understanding, we construct the actual meaning of the term based on a number of linguistic clues, both internal to the document and external from our prior experiences. In particular, there are at least five notions from linguistics that can help shape a more consistent claim construction methodology: 1) every reader, including a judge, possesses a mental lexicon with a common sense (or conventional) understanding of word meaning which is a point from which to start when interpreting claims; 2) there is an appropriate place for dictionary usage, which is to inform the judge's common sense understanding about a word where he has none; 3) patent claims have their own grammar which must inform the syntactical and contextual analysis, but may also skew the reader's common understanding that was obtained either from a mental lexicon or from a dictionary; 4) regardless of the common sense understanding, the PHOSITA must be returned to the analysis and changes made to the law to effectuate the return of the PHOSITA; and 5) extensive resort to the specification and prosecution history to divine the patentee's intent is inappropriate.
Antecedents and Effects of Parent Control in International Joint Ventures

Using a sample of 90 US–China manufacturing joint ventures, this study empirically tested a grounded-theory model of the antecedents and the effects of the structure of parent management control in international joint ventures. The results suggest that competitive and cooperative dynamics occur simultaneously between joint venture partners. On one hand, the relative bargaining power between the partners, derived from the negotiation context and from contributing critical resources to the venture, respectively, is a determining factor in management control; and the level of operational control exercised by a partner over the venture has a positive effect on the extent to which this partner's strategic objectives are achieved. On the other hand, the quality of the interpartner working relationship was found to have a strong, positive relationship with the achievement of strategic objectives for both partners.
Survival Analysis on Rare Events Using Group-Regularized Multi-Response Cox Regression.

MOTIVATION The prediction performance of Cox proportional hazard model suffers when there are only few uncensored events in the training data. RESULTS We propose a Sparse-Group regularized Cox regression method to improve the prediction performance of large-scale and high-dimensional survival data with few observed events. Our approach is applicable when there is one or more other survival responses that 1. has a large number of observed events; 2. share a common set of associated predictors with the rare event response. This scenario is common in the UK Biobank (Sudlow et al., 2015) dataset where records for a large number of common and less prevalent diseases of the same set of individuals are available. By analyzing these responses together, we hope to achieve higher prediction performance than when they are analyzed individually. To make this approach practical for large-scale data, we developed an accelerated proximal gradient optimization algorithm as well as a screening procedure inspired by Qian et al. (2020). AVAILABILITY https://github.com/rivas-lab/multisnpnet-Cox. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
Doloresite, A New Vanadium Oxide Mineral from the Colorado Plateau

k Occurrence o 5 Physical and chemical properties 6 Chemical analysis 9 X-ray crystallography a ........ 11 Summary iMReferences <, 15
The Variance Learning Curve

The expansive learning curve literature in operations management has established how various facets of prior experience improve average performance. In this paper, we explore how increased cumulati...
Two-color differential dynamic microscopy for capturing fast dynamics

Differential dynamic microscopy (DDM) is increasingly used in the fields of soft matter physics and biophysics to extract the dynamics of microscopic objects across a range of wavevectors by optical microscopy. Standard DDM is limited to detecting dynamics no faster than the camera frame rate. We report on an extension to DDM where we sequentially illuminate the sample with spectrally distinct light and image with a color camera. By pulsing blue and then red light separated by a lag time much smaller than the camera’s exposure time, we are able to use this two-color DDM method to measure dynamics occurring much faster than the camera frame rate.
Prema : Principled Tensor Data Recovery From Multiple Aggregated Views

Multidimensional data have become ubiquitous and are frequently encountered in situations where the information is aggregated over multiple data atoms. The aggregation can be over time or other features, such as geographical location. We often have access to multiple aggregated views of the same data, each aggregated in one or more dimensions, especially when data are collected or measured by different agencies. For instance, item sales can be aggregated temporally, and over groups of stores based on their location or affiliation. However, data mining and machine learning models benefit from detailed data for personalized analysis and prediction. Thus, data disaggregation algorithms are becoming increasingly important in various domains. The goal of this paper is to reconstruct finer-scale data from multiple coarse views, aggregated over different (subsets of) dimensions. The proposed method, called Prema , leverages low-rank tensor factorization tools to fuse the multiple views and provide recovery guarantees under certain conditions. Prema can tackle challenging scenarios, such as missing or partially observed data, double aggregation, and even blind disaggregation (without knowledge of the aggregation patterns) using a variant of Prema called B-Prema . To showcase the effectiveness of Prema , the paper includes extensive experiments using real data from different domains: retail sales, crime counts, and weather observations.
Chromatin information content landscapes inform transcription factor and DNA interactions

Interactions between transcription factors and chromatin are fundamental to genome organization and regulation and, ultimately, cell state. Here, we use information theory to measure signatures of organized chromatin resulting from transcription factor-chromatin interactions encoded in the patterns of the accessible genome, which we term chromatin information enrichment (CIE). We calculate CIE for hundreds of transcription factor motifs across human samples and identify two classes: low and high CIE. The 10–20% of common and tissue-specific high CIE transcription factor motifs, associate with higher protein–DNA residence time, including different binding site subclasses of the same transcription factor, increased nucleosome phasing, specific protein domains, and the genetic control of both chromatin accessibility and gene expression. These results show that variations in the information encoded in chromatin architecture reflect functional biological variation, with implications for cell state dynamics and memory. Interaction between transcription factors and chromatin is fundamental for genome organization and regulation. Here, the authors use information theory to measure signatures of organized chromatin resulting from transcription factor-chromatin interactions, termed chromatin information enrichment, and find that variations in the information encoded in chromatin architecture reflects functional biological variation.
Deep Learning-based Symbolic Indoor Positioning using the Serving eNodeB

This paper presents a novel indoor positioning method designed for residential apartments. The proposed method makes use of cellular signals emitting from a serving eNodeB which eliminates the need for specialized positioning infrastructure. Additionally, it utilizes Denoising Autoencoders to mitigate the effects of cellular signal loss. We evaluated the pro-posed method using real-world data collected from two different smartphones inside a representative apartment of eight symbolic spaces. Experimental results verify that the proposed method outperforms conventional symbolic indoor positioning techniques in various performance metrics. To promote reproducibility and foster new research efforts, we made all the data and codes associated with this work publicly available.
SLIP Walking Over Rough Terrain via H-LIP Stepping and Backstepping-Barrier Function Inspired Quadratic Program

We present an advanced and novel control method to enable actuated Spring Loaded Inverted Pendulum model to walk over rough and challenging terrains. The high-level philosophy is the decoupling of the controls of the vertical and horizontal states. The vertical state is controlled via Backstepping-Barrier Function (BBF) based quadratic programs: a combination of control Lyapunov backstepping and control barrier function, both of which provide inequality constraints on the inputs. The horizontal state is stabilized via Hybrid-Linear Inverted Pendulum (H-LIP) based stepping, which has a closed-form formulation. Therefore, the implementation is computationally-efficient. We evaluate our method in simulation, which demonstrates the aSLIP walking over various terrains, including slopes, stairs, and general rough terrains with uncertainties.
Bottlenecks for Weil-Petersson geodesics

Abstract We introduce a method for constructing Weil-Petersson (WP) geodesics with certain behavior in the Teichmuller space. This allows us to study the itinerary of geodesics among the strata of the WP completion and its relation to subsurface projection coefficients of their end invariants. As an application we demonstrate the disparity between short curves in the universal curve over a WP geodesic and those of the associated hyperbolic 3–manifold.
On the Convergence Time of a Natural Dynamics for Linear Programming

We consider a system of nonlinear ordinary differential equations for the solution of linear programming (LP) problems that was first proposed in the mathematical biology literature as a model for the foraging behavior of acellular slime mold Physarum polycephalum, and more recently considered as a method to solve LP instances. We study the convergence time of the continuous Physarum dynamics in the context of the linear programming problem, and derive a new time bound to approximate optimality that depends on the relative entropy between projected versions of the optimal point and of the initial point. The bound scales logarithmically with the LP cost coefficients and linearly with the inverse of the relative accuracy, establishing the efficiency of the dynamics for arbitrary LP instances with positive costs.
Dispersion control in pressure-driven flow through bowed rectangular microchannels

In fully-developed pressure-driven flow, the spreading of a dissolved solute is enhanced in the flow direction due to transverse velocity variations in a phenomenon now commonly referred to as Taylor–Aris dispersion. It is well understood that the characteristics of the dispersion are sensitive to the channel’s cross-sectional geometry. Here we demonstrate a method for manipulation of dispersion in a single rectangular microchannel via controlled deformation of its upper wall. Using a rapidly prototyped multi-layer microchip, the channel wall is deformed by a controlled pressure source allowing us to characterize the dependence of the dispersion on the deflection of the channel wall and overall channel aspect ratio. For a given channel aspect ratio, an optimal deformation to minimize dispersion is found, consistent with prior numerical and theoretical predictions. Our experimental measurements are also compared directly to numerical predictions using an idealized geometry.
Statistical Recurrent Models on Manifold valued Data

In a number of disciplines, the data (e.g., graphs, manifolds) to be analyzed are non-Euclidean in nature. Geometric deep learning corresponds to techniques that generalize deep neural network models to such non-Euclidean spaces. Several recent papers have shown how convolutional neural networks (CNNs) can be extended to learn with graph-based data. In this work, we study the setting where the data (or measurements) are ordered, longitudinal or temporal in nature and live on a Riemannian manifold -- this setting is common in a variety of problems in statistical machine learning, vision, and medical imaging. We show how recurrent statistical recurrent network models can be defined in such spaces. We give an efficient algorithm and conduct a rigorous analysis of its statistical properties. We perform extensive numerical experiments showing competitive performance with state of the art methods but with far fewer parameters. We also show applications to a statistical analysis task in brain imaging, a regime where deep neural network models have only been utilized in limited ways.
Internal Capital and Investment: Evidence from 2012 Pension Relief†

We exploit pension funding relief enacted in 2012 to estimate the effects of a positive shock to internal liquidity on market prices and investment. Measuring unexpected increases in internal liquidity using a priori expected pension contributions disclosed under FAS132R, we report positive market returns around the date of Congressional approval for financially constrained firms and find that weak institutional monitoring attenuates these returns. We estimate the likelihood firms will benefit from reductions in mandatory contributions and find that financially constrained firms increase R&D expenditures in the months following the legislation and increase capital expenditures in the year following the enactment date. Overall, we provide evidence that pension disclosures provided useful information to investors in assessing the benefits of pension relief and our results shed light on the importance of capital adjustment costs for capital expenditures vis-a-vis R&D.
Quantum Sensing of Spin Fluctuations of Magnetic Insulator Films with Perpendicular Anisotropy

Nitrogen-vacancy (N-V) centers, optically active atomic defects in diamond, have been widely applied to emerging quantum sensing, imaging, and network efforts, showing unprecedented field sensitivity and nanoscale spatial resolution. Many of these advantages derive from their excellent quantum-coherence, single-spin addressability, and remarkable functionality over a broad temperature range, enabling opportunities to outperform their classical counterparts. To date, N-V measurements of spin fluctuations have mainly focused on systems with in-plane magnetization, but applications to material systems with a spontaneous out-of-plane magnetization remain largely unexplored despite their technological importance. Here, we report N-V sensing of intrinsic spin fluctuations of magnetic insulator ${\mathrm{Y}}_{3}{\mathrm{Fe}}_{5}{\mathrm{O}}_{12}$ thin films with perpendicular magnetic anisotropy. The measured field dependence of N-V relaxation rates is well correlated to the variation of magnon density and band structure of the magnetic samples, which are challenging to access by the conventional magnetometry methods. Our results highlight the significant opportunities offered by N-V centers in diagnosing the noise environment of functional magnetic elements, providing valuable information to develop next-generation, high-density, and scalable spintronic devices.
Limit Theorems for Conservative Flows on Multiple Stochastic Integrals

We consider a stationary sequence $$(X_n)$$ constructed by a multiple stochastic integral and an infinite-measure conservative dynamical system. The random measure defining the multiple integral is non-Gaussian and infinitely divisible and has a finite variance. Some additional assumptions on the dynamical system give rise to a parameter $$\beta \in (0,1)$$ quantifying the conservativity of the system. This parameter $$\beta $$ together with the order of the integral determines the decay rate of the covariance of $$(X_n)$$ . The goal of the paper is to establish limit theorems for the partial sum process of $$(X_n)$$ . We obtain a central limit theorem with Brownian motion as limit when the covariance decays fast enough, as well as a non-central limit theorem with fractional Brownian motion or Rosenblatt process as limit when the covariance decays slowly enough.
FROM THE SCRAPBOOK OF A TEACHER OF SCIENCE

Being some observations of the great and the near-great on the nature of the several sciences and on the art of living in general, preserved occasionally without prejudice but reproduced always with mental reservations.
Automatic Brain Tumor Segmentation with Scale Attention Network.

Automatic segmentation of brain tumors is an essential but challenging step for extracting quantitative imaging biomarkers for accurate tumor detection, diagnosis, prognosis, treatment planning and assessment. Multimodal Brain Tumor Segmentation Challenge 2020 (BraTS 2020) provides a common platform for comparing different automatic algorithms on multi-parametric Magnetic Resonance Imaging (mpMRI) in tasks of 1) Brain tumor segmentation MRI scans; 2) Prediction of patient overall survival (OS) from pre-operative MRI scans; 3) Distinction of true tumor recurrence from treatment related effects and 4) Evaluation of uncertainty measures in segmentation. We participate the image segmentation challenge by developing a fully automatic segmentation network based on encoder-decoder architecture. In order to better integrate information across different scales, we propose a dynamic scale attention mechanism that incorporates low-level details with high-level semantics from feature maps at different scales. Our framework was trained using the 369 challenge training cases provided by BraTS 2020, and achieved an average Dice Similarity Coefficient (DSC) of 0.8828, 0.8433 and 0.8177, as well as \(95\%\) Hausdorff distance (in millimeter) of 5.2176, 17.9697 and 13.4298 on 166 testing cases for whole tumor, tumor core and enhanced tumor, respectively, which ranked itself as the 3rd place among 693 registrations in the BraTS 2020 challenge.
Modulated MPC for Arm Inductor-Less MVDC MMC With Reduced Computational Burden

A modulated model predictive controller is designed for an inductor-less modular multilevel converter targeting an MVDC solid-state transformer application. The underlying optimization problem is formulated such that a unique closed-form solution is derived from a highly accurate dynamic system model, which significantly reduces computation time. Unlike other closed-form methods, the proposed controller achieves inductor-less current control, has a reduced sampling speed enabled by a novel model-based circulating energy compensator, and does not require tuned PI controllers to generate current references. Simulation and experimental results demonstrate that the proposed controller achieves transient power flow control and steady state circulating energy control despite the low system inertia.