cssi/SciSciGPT-SciSciNet huggingface dataset:
Task Classification and Strategy Utilization in Motor Skills

Abstract A task classification scheme was developed in accordance with a conceptual model of motor behavior. The scheme suggests that motor skills be categorized as to the processing demands placed on a learner, feedback availability, and pacing conditions. Additionally, potential learner strategies were identified and defined in relation to both the model and the classification scheme. Consideration was given to the fact that strategies should be taught in addition to movement skills. Ultimately, appropriate strategies should be self-generated. Recommendations were provided for the consideration of task-learner-strategy interactions in the design of instructional material and development of instructional programs.
Sulfate reduction and other sedimentary biogeochemistry in a northern New England salt marsh

Sulfate reduction rates, dissolved iron and sulfide concentrations, and titration alkalinity were measured in salt marsh soils along a transect that included areas inhabited by both the tall and short forms of Spartina alterniflora and by Spartina patens. Pore waters were collected with in situ 'sippers' to acquire temporal data from the same location without disturbing plant roots. During 1984, data collected at weekly intervals showed rapid temporal changes in belowground biogeochemical processes that coincided with changes in S. alterniflora physiology. Rates of SO4(-2) reduction increased fivefold (to greater than 2.5 micromol ml(sup -1)d(sup -1)) when plants began elongating aboveground yet decreased fourfold upon plant flowering. This rapid increase in rates of SO4(-2) reduction must have been fueled by dissolved organic matter released from roots only during active growth. Once plants flowered, the supply of oxidants to the soil decreased and sulfide and alkalinity concentrations increased despite decreases in SO4(-2) reduction and increases in SO4(-2):Cl(-) ratios. Sulfide concentrations were highest in soils inhabited by tallest plants. During 1985, S. alterniflora became infested with fly larvae (Chaetopsis apicalis John) and aboveground growth ceased in late June. This cessation was accompanied by decreased rates of SO4(-2) reduction similar to those noted during the previous year when flowering occurred. After the fly infestation, the pore-water chemical profiles of these soils resembled profiles of soils inhabited by the short form of S. alterniflora. The SO4(-2) reduction rates in S. patens soils are the first reported. Rates were similar to those in S. alterniflora except that they did not increase greatly when S. patens was elongating. Tidal and rainfall events produced desiccation-saturation cycles that altered redox conditions in the S. patens soils, resulting in rapid changes in the dissolution and precipitation of iron and in the magnitude and spatial distribution of SO4(-2) reduction.
Losing my revolution: how many resources shared on social media have been lost?

Social media content has grown exponentially in the recent years and the role of social media has evolved from just narrating life events to actually shaping them. In this paper we explore how many resources shared in social media are still available on the live web or in public web archives. By analyzing six different event-centric datasets of resources shared in social media in the period from June 2009 to March 2012, we found about 11% lost and 20% archived after just a year and an average of 27% lost and 41% archived after two and a half years. Furthermore, we found a nearly linear relationship between time of sharing of the resource and the percentage lost, with a slightly less linear relationship between time of sharing and archiving coverage of the resource. From this model we conclude that after the first year of publishing, nearly 11% of shared resources will be lost and after that we will continue to lose 0.02% per day.
Estimation and testing for the common intersection point

Abstract The problems of estimating a common intersection point from a collection of straight lines and of testing the hypothesis that such a point exists are considered. The relationship to the error-in-variables regression and to the intersection–union principle is explored. Robust rank-based procedures for this problem are suggested, and the results of Monte Carlo simulation are reported. An example of isokinetic relationship in hexachlorobiphenyl is reviewed.
On the Kinetic Energy and Radiative Efficiency of Gamma-Ray Bursts

Using measured X-ray luminosities of 17 gamma-ray bursts (GRBs) during the afterglow phase and accounting for radiative losses, we calculate the kinetic energy of these bursts and investigate its relation to other GRB properties. We then use the observed radiated energy during the prompt phase to determine the radiative efficiency of these bursts and explore how the efficiency relates to other GRB observables. We find that the kinetic energy in the afterglow phase is directly correlated with the radiated energy, total energy, and possibly the jet opening angle and spectral peak energy. More importantly, we find the intriguing fact that the efficiency is correlated with the radiated energy and mildly with the total energy, jet opening angle, and spectral peak energy. XRF 020903 also seems to follow the trends we find for our GRB sample. We discuss the implications of these results for the GRB radiation and jet models.
More holography from conformal field theory

We extend the work of [4] to support the conjecture that any conformal field theory with a large N expansion and a large gap in the spectrum of anomalous dimensions has a local bulk dual. We count to O(1/N 2 ) the solutions to the crossing constraints in conformal field theory for a completely general scalar four-point function and show that, to this order, the counting matches the number of independent interactions in a general scalar theory on Anti-de Sitter space. We introduce parity odd conformal blocks for this purpose.
Performance bounds for expander-based compressed sensing in the presence of Poisson noise

This paper provides performance bounds for compressed sensing in the presence of Poisson noise using expander graphs. The Poisson noise model is appropriate for a variety of applications, including low-light imaging and digital streaming, where the signal-independent and/or bounded noise models used in the compressed sensing literature are no longer applicable. In this paper, we develop a novel sensing paradigm based on expander graphs and propose a MAP algorithm for recovering sparse or compressible signals from Poisson observations. The geometry of the expander graphs and the positivity of the corresponding sensing matrices play a crucial role in establishing the bounds on the signal reconstruction error of the proposed algorithm. The geometry of the expander graphs makes them provably superior to random dense sensing matrices, such as Gaussian or partial Fourier ensembles, for the Poisson noise model.We support our results with experimental demonstrations.
The determinants of monetary target credibility

Abstract This paper examines the impact of several different factors on the credibility of the Federal Reserve's monetary targets. Two factors appear to explain why the targets became less credible during the 1980s. First, the Fed's shift from M1 to M2 targets reduced credibility because the latter aggregate is less controllable. Second, velocity instability caused the Fed to widen the target ranges and this action signaled that they were placing less weight on monetary targets in the conduct of monetary policy.
The graph-representation approach to topological field theory in 2 + 1 dimensions

An alternative definition of topological quantum field theory in 2 + 1 dimensions is discussed. The fundamental objects in this approach are not gauge fields as in the usual approach, but nonlocal observables associated with graphs. The classical theory of graphs is defined by postulating a simple diagrammatic rule for computing the Poisson bracket of any two graphs. The theory is quantized by exhibiting a quantum deformation of the classical Poisson-bracket algebra, which is realized as a commutator algebra on a Hilbert space of states. The wave functions in this "graph representation" approach are functionals on an appropriate set of graphs. This is in contrast to the usual "connection representation" approach, in which the theory is defined in terms of a gauge field and the wave functions are functionals on the space of flat spatial connections modulo gauge transformations.
A convenient synthesis of 2-fluoro- and 6-fluoro-(2S,3R)-threo-(3,4-dihydroxyphenyl)serine using Sharpless asymmetric aminohydroxylation

Ring-fluorinated β-hydroxy α-amino methyl esters 3b,c were synthesized enantioselectively using Sharpless asymmetric aminohydroxylation. These were converted to 2-fluoro- and 6-fluoro-(2S,3R)-threo-(3,4-dihydroxyphenyl)serine 1b,c using our previously published procedure.
Superconducting nanocomposites: enhancement of bulk pinning and improvement of intergrain coupling

Heterogeneous sonochemical method was applied for synthesis of novel superconducting nanocomposites consisting of magnetic (and/or nonmagnetic) nanoparticles embedded into the bulk of ceramic superconductors . In addition to in-situ production of the efficient pinning centers, this synthesis method considerably improves the interbrain coupling. Significant enhancement of the magnetic irreversibility is reported for Fe/sub 2/O/sub 3/ nanoparticles embedded into the bulk of MgB/sub 2/ superconductor. Nonmagnetic Mo/sub 2/O/sub 5/ nanoparticles also increase pinning strength, but less than magnetic Fe/sub 2/O/sub 3/. Detailed magnetization and electron microscopy characterization is presented. Theory of bulk magnetic pinning due to ferromagnetic nanoparticles of finite size embedded into the superconducting matrix is developed.
A Methodology for Simulating Compressible Turbulent Flows

A flow simulation Methodology (FSM) is presented for computing the time-dependent behavior of complex compressible turbulent flows. The development of FSM was initiated in close collaboration with C. Speziale (then at Boston University). The objective of FSM is to provide the proper amount of turbulence modeling for the unresolved scales while directly computing the largest scales. The strategy is implemented by using state-of-the-art turbulence models (as developed for Reynolds averaged Navier-Stokes (RANS)) and scaling of the model terms with a "contribution function." The contribution function is dependent on the local and instantaneous "physical" resolution in the computation. This physical resolution is determined during the actual simulation by comparing the size of the smallest relevant scales to the local grid size used in the computation. The contribution function is designed such that it provides no modeling if the computation is locally well resolved so that it approaches direct numerical simulations (DNS) in the fine-grid limit and such that it provides modeling of all scales in the coarse-grid limit and thus approaches a RANS calculation. In between these resolution limits, the contribution function adjusts the necessary modeling for the unresolved scales while the larger (resolved) scales are computed as in large eddy simulation (LES). However, FSM is distinctly different from LES in that it allows for a consistent transition between RANS, LES, and DNS within the same simulation depending on the local flow behavior and "physical" resolution. As a consequence, FSM should require considerably fewer grid points for a given calculation than would be necessary for a LES. This conjecture is substantiated by employing FSM to calculate the flow over a backward-facing step and a plane wake behind a bluff body, both at low Mach number, and supersonic axisymmetric wakes. These examples were chosen such that they expose, on the one hand, the inherent difficulties of simulating (physically) complex flows, and, on the other hand, demonstrate the potential of the FSM approach for simulations of turbulent compressible flows for complex geometries.
Power control in cognitive radio networks: how to cross a multi-lane highway

We consider power control in cognitive radio networks where secondary users identify and exploit instantaneous and local spectrum opportunities without causing unacceptable interference to primary users. We qualitatively characterize the impacts of the transmission power of secondary users on the occurrence of spectrum opportunities and the reliability of opportunity detection. Based on a Poisson model of the primary network, we quantify these impacts by showing that (i) the probability of spectrum opportunity decreases exponentially with the transmission power of secondary users, where the exponential decay constant is given by the traffic load of primary users; (ii) reliable opportunity detection is achieved in the two extreme regimes in terms of the ratio between the transmission power of secondary users and that of primary users. Such analytical characterizations allow us to study power control for optimal transport throughput under constraints on the interference to primary users. Furthermore, we reveal the difference between detecting primary signals and detecting spectrum opportunities, and demonstrate the complex relationship between physical layer spectrum sensing and MAC layer throughput. The dependency of this PHY-MAC interaction on the application type and the use of handshake signaling such as RTS/CTS is also illustrated.
Universal Test Sets for Logic Networks

This paper examines the problem of finding a single universal test set that will test any of a variety of different implementations of a given switching function. It is shown that, for AND/OR networks, universal test sets may be found that detect not only all single faults but all multiple faults as well. The minimality and size of these sets are examined and their derivation for incomplete functions is described.
An approach to eliminate roundoff errors in digital filters

"Second-order quantizers" are introduced which can be used for implementing recursive digital filters with practically no roundoff errors or limit-cycle oscillations. Based on the idea of changing the transfer function used to compute roundoff errors, these quantizers save the low-order bits to correct the product at future iterations. For several pole locations, this can be done with a minimal amount of extra hardware.
Bailouts and Financial Fragility

How does the belief that policymakers will bail out investors in the event of a crisis affect the allocation of resources and the stability of the financial system? I study this question in a model of financial intermediation with limited commitment. When a crisis occurs, the efficient policy response is to use public resources to augment the private consumption of those investors facing losses. The anticipation of such a “bailout” distorts ex ante incentives, leading intermediaries to choose arrangements with excessive illiquidity and thereby increasing financial fragility. Prohibiting bailouts is not necessarily desirable, however: it induces intermediaries to become too liquid from a social point of view and may, in addition, leave the economy more susceptible to a crisis. A policy of taxing short-term liabilities, in contrast, can correct the incentive problem while improving financial stability.
Communicating health information to disadvantaged populations.

Paper presented at the 1st International Symposium on Understanding Health Benefits and Risks: Empowering Patients and Citizens Johns Hopkins University, Baltimore, Maryland May 29, 2009
Some properties of plausible reasoning

This paper presents a plausible reasoning system to illustrate some broad issues in knowledge representation: dualities between different reasoning forms, the difficulty of unifying complementary reasoning styles, and the approximate nature of plausible reasoning. These issues have a common underlying theme: there should be an underlying belief calculus of which the many different reasoning forms are special cases, sometimes approximate. The system presented allows reasoning about defaults, likelihood, necessity and possibility in a manner similar to the earlier work of Adams. The system is based on the belief calculus of subjective Bayesian probability which itself is based on a few simple assumptions about how belief should be manipulated. Approximations, semantics, consistency and consequence results are presented for the system. While this puts these often discussed plausible reasoning forms on a probabilistic footing, useful application to practical problems remains an issue.
Pummerer reaction methodology for the synthesis of 5-thiophenyl substituted oxazoles

Abstract Treatment of N -acylamino-2-thiophenyl derivatives with N -chlorosuccinimide (2.0 equiv.) followed by SnCl 4 (0.1–1.0 equiv.) provides a direct synthesis of 5-thiophenyloxazoles.
A convenient synthesis of coumarin-3-carboxylic acids via Knoevenagel condensation of Meldrum's acid with ortho-hydroxyaryl aldehydes or ketones

Coumarin-3-carboxylic acids were obtained in high yields with excellent purity from ortho-hydroxybenzaldehydes and Meldrum's acid after a 2 h reflux in ethanol. The less reactive ketones were first reacted with alcoholic ammonia to form ketimines, which were then condensed with Meldrum's acid to generate 4-alkylcoumarin-3-carboxylic acids in moderate yields.
Q-learning of complex behaviours on a six-legged walking machine

We present work on a six-legged walking machine that uses a hierarchical version of [C.J.C.H. Watkins, Learning with delayed rewards, Ph.D. Thesis, Psychology Department, Cambridge University, 1989] Q-learning (HQL) to learn both: the elementary swing and stance movements of individual legs as well as the overall coordination scheme to perform forward movements. The architecture consists of a hierarchy of local controllers implemented in layers. The lowest layer consists of control modules performing elementary actions, like moving a leg up, down, left or right to achieve the elementary swing and stance motions for individual legs. The next level consists of controllers that learn to perform more complex tasks like forward movement by using the previously learned, lower level modules. The work is related to similar, although simulation based, work [L.J. Lin, Reinforcement learning for robots using neural networks, Ph.D. Thesis, Carnegie Mellon University, 1993] on hierarchical reinforcement-learning and [S.P. Singh, learning to solve Markovian decision problems, Ph.D. Thesis, Department of Computer Science at the University of Massachusetts, 1994] on compositional Q-learning. We report on the HQL architecture as well as on its implementation on the walking machine Sir Arthur. Results from experiments carried out on the real robot are reported to show the applicability of the HQL approach to real world robot problems.
Reparations for ‘Guilty Victims’: Navigating Complex Identities of Victim–Perpetrators in Reparation Mechanisms

Reparations are often declared victim-centred, but in transitional societies defining who is a victim and eligible for reparations can be politically charged and controversial. The messy reality of conflict means that perpetrators and victims do not always fall into two separate categories. In certain circumstances, perpetrators can be victimized and victims can be responsible for victimizing others – this article explores these complex victims. Looking in particular at the 1993 Shankill bombing in Northern Ireland, as well as at Colombia and Peru, such victims are often seen as ‘guilty’ or ‘bad’ victims undeserving of reparations. I argue that complex victims need to be included in reparation mechanisms to ensure accountability and to prevent their exclusion becoming a source of victimization and future violence. I consider the alternative avenues of human rights courts, development aid, services and community reparations to navigate complex identities of victim–perpetrators. I conclude that complex identities can be accommodated in transitional societies’ reparation programmes through nuanced rules of eligibility and forms of reparations.
Design of Arch Dams by Trial Load Method of Analysis

Basic principles of trial-load method of stress analysis; various types of analyses, and their advantages and limitations; economical design and saving in design time by use of trial-load method of stress analysis; examples.
An infinite family of excluded minors for strong base-orderability

Abstract We discuss a conjecture of Ingleton on excluded minors for base-orderability, and, extending a result he stated, we prove that infinitely many of the matroids that he identified are excluded minors for base-orderability, as well as for the class of gammoids. We prove that a paving matroid is base-orderable if and only if it has no M ( K 4 ) -minor. For each k ≥ 2 , we define the property of k -base-orderability, which lies strictly between base-orderability and strong base-orderability, and we show that k -base-orderable matroids form what Ingleton called a complete class. By generalizing an example of Ingleton, we construct a set of matroids, each of which is an excluded minor for k -base-orderability, but is ( k − 1 ) -base-orderable; the union of these sets, over all k , is an infinite set of base-orderable excluded minors for strong base-orderability.
A Monte Carlo exploration of threefold base geometries for 4d F-theory vacua

We use Monte Carlo methods to explore the set of toric threefold bases that support elliptic Calabi-Yau fourfolds for F-theory compactifications to four dimensions, and study the distribution of geometrically non-Higgsable gauge groups, matter, and quiver structure. We estimate the number of distinct threefold bases in the connected set studied to be ∼ 1048. The distribution of bases peaks around h 1,1 ∼ 82. All bases encountered after “thermalization” have some geometric non-Higgsable structure. We find that the number of non-Higgsable gauge group factors grows roughly linearly in h 1,1 of the threefold base. Typical bases have ∼ 6 isolated gauge factors as well as several larger connected clusters of gauge factors with jointly charged matter. Approximately 76% of the bases sampled contain connected two-factor gauge group products of the form SU(3) × SU(2), which may act as the non-Abelian part of the standard model gauge group. SU(3) × SU(2) is the third most common connected two-factor product group, following SU(2) × SU(2) and G 2 × SU(2), which arise more frequently.
Municipal Development of Oil and Gas

After reviewing the basic powers conferred upon municipalities, the author advances a proposal whereby cities can actively promote and develop oil and gas. To assist cities with such development he advocates the use of certain model ordinances, resolutions, and lease provisions. He also analyzes various legal problems confronting municipal development of oil and gas, and concludes that municipalities have the proper tools to develop such resources and still accommodate all parties involved.
Good manners: signaling social preferences

Certain messages, even when not directly payoff relevant, can be a credible form of communication in light of natural social preferences. Social image concerns and other-regarding preferences interact to create incentives to communicate about how one feels about other people. Recognizing the prevalence of the incentive to communicate about one’s social preferences suggests that many social and economic phenomena—from norms of etiquette to cooperation to gift exchange—should be seen, in part, as forms of signaling. These behaviors may be surprisingly robust to material costs, yet sensitive to context.
Monotone Instrumental Variables: With an Application to the Returns to Schooling

FOR FIFTY YEARS ECONOMETRIC ANALYSES of treatment response have made extensive use of instrumental variable (IV) assumptions holding that mean response is constant across specified subpopulations of a population of interest.2 Yet the credibility of mean independence conditions and other IV assumptions has often been a matter of considerable disagreement, with much debate about whether some covariate is or is not a "valid instrument" in an application of interest. There is therefore good reason to consider weaker but more credible assumptions. To this end, we introduce monotone instlumental variable (MIV) assumptions holding that mean response varies weakly monotonically across specified subpopulations. We study the identifying power of these MIV assumptions and give an empirical application. The findings reported here add to the literature developing nonparametric bounds on treatment effects.3 This paper uses the same formal setup as Manski (1997). There is a probability space (J, X2, P) of individuals. Each member j of population J has observable covariates xi E X and a response function yj( ): T -> Y mapping the mutually exclusive and exhaustive treatments t E T into outcomes yj(t) E Y. Person j has a realized treatment zj E T and a realized outcome y 1 -y(zi), both of which are observable. The latent outcomes yj(t),
Rigid supersymmetric backgrounds of 3-dimensional Newton-Cartan supergravity

Recently, a non-relativistic off-shell formulation of three dimensional Newton-Cartan supergravity was proposed as the c → ∞ limit of three dimensional $$ \mathcal{N} $$ = 2 super-gravity [1]. In the present paper we study supersymmetric backgrounds within this theory. Using integrability constraints for the non-relativistic Killing spinor equations, we explicitly construct all maximally supersymmetric solutions, which admit four supercharges. In addition to these solutions, there are $$ \frac{1}{2} $$ -BPS solutions with reduced supersymmetry. We give explicit examples of such backgrounds and derive necessary conditions for backgrounds preserving two supercharges. Finally, we address how supersymmetric backgrounds of $$ \mathcal{N} $$ = 2 supergravity are connected to the solutions found here in the c → ∞ limit.
Classifying Data to Reduce Long-Term Data Movement in Shingled Write Disks

Shingled magnetic recording (SMR) is a means of increasing the density of hard drives that brings a new set of challenges. Due to the nature of SMR disks, updating in place is not an option. Holes left by invalidated data can only be filled if the entire band is reclaimed, and a poor band compaction algorithm could result in spending a lot of time moving blocks over the lifetime of the device. We propose using write frequency to separate blocks to reduce data movement and develop a band compaction algorithm that implements this heuristic. We demonstrate how our algorithm results in improved data management, resulting in an up to 45p reduction in required data movements when compared to naive approaches to band management.
Spatial and temporal patterns in Arctic river ice breakup revealed by automated ice detection from MODIS imagery

Abstract The annual spring breakup of river ice has important consequences for northern ecosystems and significant economic implications for Arctic industry and transportation. River ice breakup research is restricted by the sparse distribution of hydrological stations in the Arctic, where limited available data suggests a trend towards earlier ice breakup. The specific climatic mechanisms driving this trend, however, are complex and can vary both regionally and within river systems. Consequently, understanding the response of river ice processes to a warming Arctic requires simultaneous examination of spatial and temporal patterns in breakup timing. In this paper, we describe an automated algorithm for river ice breakup detection using MODIS satellite imagery that enables identification of spatial and temporal breakup patterns at large scales. We examine breakup timing on the Mackenzie, Lena, Ob' and Yenisey rivers for the period 2000–2014. By dividing the rivers into 10 km segments and classifying each river pixel in each segment as snow/ice, mixed ice/water or open water based on MODIS reflectance, we determine breakup dates with a mean uncertainty of ± 1.3 days. All statistically significant temporal trends are negative, indicating an overall shift towards earlier breakup. Considerable variability in the statistical significance and magnitude of trends along each river suggests that different climatic and physiographic drivers are impacting spatial patterns in breakup. Trends detected on the lower Mackenzie corroborate recent studies indicating weakening ice resistance and earlier breakup timing near the Mackenzie Delta. In Siberia, the increased magnitude of trends upstream and strong correlation between breakup initiation and whole-river breakup patterns suggest that earlier onset of upstream discharge may play the dominant role in determining breakup timing. Exploratory analysis demonstrates that MODIS imagery may also be used to differentiate thermal and mechanical breakup events.
Workplace-anchored migration in US counties

Residential amenities and access to employment are major factors in migration decisions. Yet traditional migration models are unable to reveal the causes (and effects) of migration because current data capture only movers who change their place of residence; depending on how far they move, these migrants may or may not also change their jobs. Migration flows thus could be categorized into two groups depending on whether the migrants also change their workplace. In this paper, we identify the number of movers who do and do not change their workplace by using overlapping county-to-county migration and commuting data. We refer to this as workplace-anchored and unanchored migration. Then we compare the local factors that affect both types of migration. Our analysis reveals that the most important local factors that separate workplace-anchored and unanchored migration are the poverty rate, commuting time, and age demographics of the origin and destination counties.
A System to Study Aneuploidy In Vivo

Aneuploidy, an imbalanced chromosome number, is associated with both cancer and developmental disorders such as Down syndrome (DS). To determine how aneuploidy affects cellular and organismal physiology, we have developed a system to evaluate aneuploid cell fitness in vivo. By transplanting hematopoietic stem cells (HSCs) into recipient mice after ablation of recipient hematopoiesis by lethal irradiation, we can directly compare the fitness of HSCs derived from a range of aneuploid mouse models with that of euploid HSCs. This experimental system can also be adapted to assess the interplay between aneuploidy and tumorigenesis. We hope that further characterization of aneuploid cells in vivo will provide insight both into the origins of hematopoietic phenotypes observed in DS individuals as well as the role of different types of aneuploid cells in the genesis of cancers of the blood.
Modeling Price Transmission between Farm and Retail Prices: A Soft Switches Approach

Vector error correction models (VECM) are used to model price transmission when farm and retail prices are cointegrated. To allow for nonlinearity in the cointegration process, researchers may specify thresholds to break the error correction process into regimes according to whether the retail price is above, below, or close to its equilibrium value given farm prices. However, because the coefficients in a VECM can change when there is movement from one regime to another, the model can be discontinuous. This implies sudden, “hard” regime changes. In this study, we extend the threshold VECM to include features of smooth transition autoregression (STAR) models. Our approach allows for gradual, soft regime changes. An empirical application to retail cheese and farm milk prices is presented.
An integral-factorized implementation of the driven similarity renormalization group second-order multireference perturbation theory.

We report an efficient implementation of a second-order multireference perturbation theory based on the driven similarity renormalization group (DSRG-MRPT2) [C. Li and F. A. Evangelista, J. Chem. Theory Comput. 11, 2097 (2015)]. Our implementation employs factorized two-electron integrals to avoid storage of large four-index intermediates. It also exploits the block structure of the reference density matrices to reduce the computational cost to that of second-order Moller–Plesset perturbation theory. Our new DSRG-MRPT2 implementation is benchmarked on ten naphthyne isomers using basis sets up to quintuple-ζ quality. We find that the singlet-triplet splittings (ΔST) of the naphthyne isomers strongly depend on the equilibrium structures. For a consistent set of geometries, the ΔST values predicted by the DSRG-MRPT2 are in good agreements with those computed by the reduced multireference coupled cluster theory with singles, doubles, and perturbative triples.
Obfuscation-Based Non-black-box Simulation and Four Message Concurrent Zero Knowledge for NP

We show the following result: Assuming the existence of public-coin differing-input obfuscation (pc-diO) for the class of all polynomial time Turing machines, then there exists a four message, fully concurrent zero-knowledge proof system for all languages in NP with negligible soundness error. This result is constructive: given (pc-diO), our reduction yields an explicit protocol along with an explicit simulator that is “straight line” and runs in strict polynomial time. The obfuscation security property is used only to prove soundness.
Forbidden information

Godel Incompleteness Theorem leaves open a way around it, vaguely perceived for a long time but not clearly identified. (Thus, Godel believed informal arguments can answer any math question.) Closing this loophole does not seem obvious and involves Kolmogorov complexity. (This is unrelated to, well studied before, complexity quantifications of the usual Godel effects.) I consider extensions U of the universal partial recursive predicate (or, say, Peano Arithmetic). I prove that any U either leaves an n-bit input (statement) unresolved or contains nearly all information about the n-bit prefix of any r.e. real ρ (which is n bits for some ρ). I argue that creating significant information about a specific math sequence is impossible regardless of the methods used. Similar problems and answers apply to other unsolvability results for tasks allowing multiple solutions, for example, nonrecursive tilings.
Expanding Employment Discrimination Protections for Individuals with Disabilities: Evidence from California:

Effective 2001, California passed the Prudence Kay Poppink Act which broadened California's disability employment discrimination law to cover individuals with less severe disabilities by lowering the burden of proof to establish a disability. I estimate how this act affected the labor market outcomes for individuals with disabilities using both difference-in-differences and difference-in-differences-in-differences regression analyses and data from the Current Population Survey. The results suggest that the act signii¬cantly increased employment, with the effect persisting at least partially up to six years later.
The Best Mixing Time for Random Walks on Trees

We characterize the extremal structures for mixing walks on trees that start from the most advantageous vertex. Let $$G=(V,E)$$G=(V,E) be a tree with stationary distribution $$\pi $$ź. For a vertex $$v \in V$$vźV, let $$H(v,\pi )$$H(v,ź) denote the expected length of an optimal stopping rule from v to $$\pi $$ź. The best mixing time for G is $$\min _{v \in V} H(v,\pi )$$minvźVH(v,ź). We show that among all trees with $$|V|=n$$|V|=n, the best mixing time is minimized uniquely by the star. For even n, the best mixing time is maximized by the uniquely path. Surprising, for odd n, the best mixing time is maximized uniquely by a path of length $$n-1$$n-1 with a single leaf adjacent to one central vertex.
A Fast Unified Model for Parsing and Sentence Understanding

Tree-structured neural networks exploit valuable syntactic parse information as they interpret the meanings of sentences. However, they suer from two key technical problems that make them slow and unwieldyforlarge-scaleNLPtasks: theyusually operate on parsed sentences and they do not directly support batched computation. We address these issues by introducingtheStack-augmentedParser-Interpreter NeuralNetwork(SPINN),whichcombines parsing and interpretation within a single tree-sequence hybrid model by integrating tree-structured sentence interpretation into the linear sequential structure of a shiftreduceparser. Ourmodelsupportsbatched computation for a speedup of up to 25◊ over other tree-structured models, and its integrated parser can operate on unparsed data with little loss in accuracy. We evaluate it on the Stanford NLI entailment task and show that it significantly outperforms other sentence-encoding models.
Synthesis of Highly Functionalized Tri- and Tetrasubstituted Alkenes via Pd-Catalyzed 1,2-Hydrovinylation of Terminal 1,3-Dienes

An efficient method for the construction of Csp2–Csp3 bond in a regio- and stereoselective fashion involving 1,3-terminal dienes, enol triflates/nonaflates, and sodium formate under Pd(0)-catalysis is described. The three component assembly allows trapping of a π-allyl intermediate, after the initial migratory insertion of the diene, by a hydride source that leads to structurally complex and synthetically challenging tri- and tetrasubstituted alkene building blocks.
Chemotaxis of Culex Pipiens Quinquefasciatus Larvae (Diptera: Culicidae) in Response to Amino Acids

A mixture of amino acids, viz., casein hydrolyzate, has been shown to induce positive chemotaxis in larvae of Culex pipiens quinquefasciatus . Individual amino acids had varying abilities to attract the larvae. Studies using phenylalanine suggested that attraction involves stereoisomerism; the L-form was strongly attractive, whereas the D-isomer was ineffective, if not repellent.
Superhard Nanocomposite of Nitride Superlattices by Opposed-Cathode Unbalanced Magnetron Sputtering

Nanocomposite films of polycrystalline nitride superlattices with nanometer grain size were deposited onto tool steel substrates by a one-step process using an opposed-cathode high-rate reactive unbalanced magnetron sputtering system. The superlattices are composed of alternating thin layers of different nitrides such as TiN/NbN and TiN/VN. The thicknesses of two neighboring layers were between 3 and 150 nm and were determined by the rotating speed of the substrate holder and the sputtering rate of the individual layer material. The films exhibited exceptional hardness as high as 5200 kgf/mm2 for TiN/NbN superlattice and 5 100 kgf/mm2 for TiN/VN superlattice. The hardnesses of the superlattice coatings were strongly dependent on several deposition parameters such as the superlattice period, the nitrogen partial pressure, and the substrate bias voltage. One of the possible mechanisms for the hardness enhancement is the effect of nanophase materials, which were created mainly by the influence of the artificially layered-structure and the low energy ion bombardment during film growth.
The Importance of Getting Names Right: The Myth of Markets for Water

Markets are much in vogue as ideal institutions for managing water both nationally and internationally. Markets are presented as functioning automatically and nearly painlessly. True markets, however, have seldom existed for water rights and there are good reasons for believing that they seldom will. Water is an ambient resource where the actions of any one user necessarily affect many other users. It is, in fact, no accident that water metaphors have long been used by economists to describe situations where markets fail: common pool resources; spill over effects; etc. Thus, if true markets are to be relied on to allocate for particular uses and distribute water among users, the transaction costs of organizing contracts with all holders of water rights (let alone those holding less formal claims affected by a sale or lease) generally have been and will be prohibitive. Water, in short, is the quintessential public good for which markets simply do not work.
Evaluation and Management of Chronic Pancytopenia

1. Richa Sharma, MD* 2. Grzegorz Nalepa, MD, PhD*,† 1. *Department of Pediatrics, Division of Pediatric Hematology-Oncology, Indiana University School of Medicine, Indianapolis, IN. 2. †Department of Medical and Molecular Genetics and Department of Biochemistry, Indiana University School of Medicine; Bone Marrow Failure Program, Riley Hospital for Children at IU Health, Indianapolis, IN. Diagnostic evaluation and management of children with chronic pancytopenia is highly complex. (1)(2)(3) Clinicians should be aware of the subtle signs and symptoms of acquired and congenital childhood pancytopenias to maintain a high index of suspicion, streamline the referral process, and function within their patients’ multidisciplinary medical homes. After completing this article, readers should be able to: 1. Identify signs and symptoms of pancytopenia. 2. Identify patients who require emergency referral due to a life-threatening illness. 3. Discuss the basics of clinical presentation, diagnostics, and management of childhood severe aplastic anemia. 4. Discuss the basics of clinical presentation, diagnostics, and management of common genetic syndromes associated with pancytopenia. 5. Understand the basic concepts behind laboratory tests and be aware of which tests are appropriate in specific clinical situations. Pancytopenia is characterized by a decreased number of at least two blood cell lines. Pancytopenia may progress acutely, such as with decreased blood cell counts in fulminant sepsis, disseminated intravascular coagulation, or rapid hemolysis. Alternatively, pancytopenia may evolve insidiously over weeks to months. In this review we focus on the latter group of acquired and congenital pancytopenias in children. Chronic pancytopenia is a diagnostic challenge. The range of potential causes is bewildering, signs and symptoms overlap substantially, and many diseases presenting with pancytopenia are life-threatening if not recognized and managed properly. Therefore, clinicians must be familiar with clinical scenarios that should prompt evaluation of blood counts and a pediatric hematology referral. ### Causes Pancytopenia may be …
Fluidic Control of Asymmetric Forces on a Body of Revolution

The aerodynamic steering forces and moments on an axisymmetric bluff body are controlled by exploiting induced asymmetric, segmented attachment of the base flow to a Coanda surface on a circular tail end. Control is effected by an array of four individuallyaddressable, aft-facing synthetic jet actuators that emanate from azimuthally-segmented slots, equally distributed around the perimeter of the tail. The model is suspended in the wind tunnel by eight thin wires each instrumented with a miniature strain gage sensor for direct dynamic force measurements with minimal support interference with the wake. The aerodynamic effects associated with quasi-steady and transitory asymmetric activation of the Coanda effect are characterized using force and hot wire measurements. Transitory modulation of the actuation waveform of multiple actuators leads to the generation of significant dynamic side forces of controlled magnitude and direction with potential utility for flight stabilization and fast maneuvering.
Tying Down Loose Ends in the Chlamydomonas genome: Functional Significance of Abundant Upstream Open Reading Frames

The Chlamydomonas genome has been sequenced, assembled, and annotated to produce a rich resource for genetics and molecular biology in this well-studied model organism. The annotated genome is very rich in open reading frames upstream of the annotated coding sequence ('uORFs'): almost three quarters of the assigned transcripts have at least one uORF, and frequently more than one. This is problematic with respect to the standard 'scanning' model for eukaryotic translation initiation. These uORFs can be grouped into three classes: class 1, initiating in-frame with the coding sequence (CDS) (thus providing a potential in-frame N-terminal extension); class 2, initiating in the 5' untranslated sequences (5UT) and terminating out-of-frame in the CDS; and class 3, initiating and terminating within the 5UT. Multiple bioinformatics criteria (including analysis of Kozak consensus sequence agreement and BLASTP comparisons to the closely related Volvox genome, and statistical comparison to cds and to random sequence controls) indicate that of ∼4000 class 1 uORFs, approximately half are likely in vivo translation initiation sites. The proposed resulting N-terminal extensions in many cases will sharply alter the predicted biochemical properties of the encoded proteins. These results suggest significant modifications in ∼2000 of the ∼20,000 transcript models with respect to translation initiation and encoded peptides. In contrast, class 2 uORFs may be subject to purifying selection, and the existent ones (surviving selection) are likely inefficiently translated. Class 3 uORFs are found in more than half of transcripts, frequently multiple times per transcript; however, they are remarkably similar to random sequence expectations with respect to size, number, and composition, and therefore may in most cases be selectively neutral.
Type II interferon promotes differentiation of myeloid-biased hematopoietic stem cells

Interferon gamma (IFNγ) promotes cell division of hematopoietic stem cells (HSCs) without affecting the total HSC number. We postulated that IFNγ stimulates differentiation of HSCs as part of the innate immune response. Here, we report that type II interferon signaling is required, both at baseline and during an animal model of LCMV infection, to maintain normal myeloid development. By separately evaluating myeloid-biased and lymphoid-biased HSC subtypes, we found that myeloid-biased HSCs express higher levels of IFNγ receptor and are specifically activated to divide after recombinant IFNγ exposure in vivo. While both HSC subtypes show increased expression of the transcription factor C/EBPβ after infection, only the myeloid-biased HSCs are transiently depleted from the marrow during the type II interferon-mediated immune response to Mycobacterium avium infection, as measured both functionally and phenotypically. These findings indicate that IFNγ selectively permits differentiation of myeloid-biased HSCs during an innate immune response to infection. This represents the first report of a context and a mechanism for discriminate utilization of the alternate HSC subtypes. Terminal differentiation, at the expense of self-renewal, may compromise HSC populations during states of chronic inflammation.
Spin-Transfer Torque Switching in Nanopillar Superconducting-Magnetic Hybrid Josephson Junctions

Although both superconducting and magnetic devices have the potential to overcome limitations of current CMOS technology, traditionally they have remained separate areas of research. Here the authors develop nanopillar Josephson junctions with pseudo-spin-valve barriers that provide a unique, hybrid superconducting-magnetic capability. The states of these devices are written using spin-transfer torque and read using Josephson coupling, and yield 10-fold changes in superconducting critical current. This approach holds the promise for nanoscale, nonvolatile, cryogenic memory in future ultralow-power computing systems.
The Ultimate Properties of Simple Elastomers

Abstract The ultimate properties of polymers are very poorly understood. A large mass of practical data is available but at present there seem to be no molecular theories for its correlation or for use as a guide in obtaining new data. In the following pages a theoretical approach to the ultimate properties of simple crosslinked elastomers will be described. The treatment will be limited to the tensile strength and ultimate elongation at temperatures high enough so that crystallinity and the viscous work during extension are negligible. The theory can be extended to cover compressive or shear strength with relatively little effort. The incorporation of the effects of viscosity and crystallinity will require somewhat more work. (After the completion of the major part of this work I learned that Prof. F. Bueche, University of Wyoming, has developed a somewhat similar theory for the tensile strength of viscous elastomers.)