cssi/SciSciGPT-SciSciNet huggingface dataset:
Expectations of Returns and Expected Returns

We analyze time-series of investor expectations of future stock market returns from six data sources between 1963 and 2011. The six measures of expectations are highly positively correlated with each other, as well as with past stock returns and with the level of the stock market. However, investor expectations are strongly negatively correlated with model-based expected returns. We reconcile the evidence by calibrating a simple behavioral model, in which fundamental traders require a premium to accommodate expectations shocks from extrapolative traders, but markets are not efficient.
New Insights on the Organization of Agricultural Research: Theory and Evidence for Western Developed Countries

New Insights on the Organization of Agricultural Research: Theory and Evidence for Western Developed Countries by Wallace E. Huffman Public and private R&D are important sources of advances in knowledge leading to new technologies for and products from agriculture in western developed countries. Over the past fifteen years, a significant reduction in the rate of growth of public funding for agricultural research in western developed countries has occurred relative to the preceding decade. The future, however, holds unexplored options for the organization of public agricultural research. Advances in the theory of impure public goods can be applied to create new financing jurisdictions and funding sources for public agricultural research. Advances in principal-agent theory can be applied to the unique characteristics of the R&D production process, i.e., output is highly uncertain and administrators cannot effectively monitor scientists’ effort, to design incentive compatible contracts that significantly improve scientists’ attention to effort and quality of research payoffs. Some implications for alternative funding mechanisms are developed. The paper concludes with several new insights about the likely organization of agricultural research in western developed countries for the 21st century.
Angular Momentum and Galaxy Formation Revisited: Effects of Variable Mass-to-light Ratios

We rederive the relation between the specific angular momentum}. and the mass M. of the stellar matter in galaxies of different morphological types. Thi s is a revision of the j.- M. di agram presented in our recent comprehensive stud y of galac tic angular momentum. In that work, we estimated }. fro m kinematic and photometric data that extended to large radii and M. from near-infrared luminosities LK with an assumed universal mass-to-light ratio M.j L K. However, recent stellar populatio n models show large variations in M.j LK correlated with B - V color. In the present work, we use this correlation to estimate M.j L K and hence M. fro m the measured B - V and LK. Our rev ised j.- M. diagram is simila r to our prev ious one; both disk-dominated and elliptical galaxies follow nearly parallel seque nces with }. <X M: and a = 0 .6 ± 0.1. However, the offset between the seque nces is now a factor of about 5, some 30% larger tha n before (and c lose to the offset found by Fall in 1983). Thus, our new results place even tighter constraints on the loss of s pecific angular momentum by galactic disks over their lifeti mes.
Elastic wave propagation and attenuation in a double-porosity dual-permeability medium

Abstract To account for large-volume low-permeability storage porosity and low-volume high-permeability fracture/crack porosity in oil and gas reservoirs, phenomenological equations for the poroelastic behavior of a double porosity medium have been formulated and the coefficients in these linear equations identified. This generalization from a single porosity model increases the number of independent inertial coefficients from three to six, the number of independent drag coefficients from three to six, and the number of independent stress–strain coefficients from three to six for an isotropic applied stress and assumed isotropy of the medium. The analysis leading to physical interpretations of the inertial and drag coefficients is relatively straightforward, whereas that for the stress–strain coefficients is more tedious. In a quasistatic analysis, the physical interpretations are based upon considerations of extremes in both spatial and temporal scales. The limit of very short times is the one most pertinent for wave propagation, and in this case both matrix porosity and fractures are expected to behave in an undrained fashion, although our analysis makes no assumptions in this regard. For the very long times more relevant to reservoir drawdown, the double porosity medium behaves as an equivalent single porosity medium. At the macroscopic spatial level, the pertinent parameters (such as the total compressibility) may be determined by appropriate field tests. At the mesoscopic scale, pertinent parameters of the rock matrix can be determined directly through laboratory measurements on core, and the compressibility can be measured for a single fracture. We show explicitly how to generalize the quasistatic results to incorporate wave propagation effects and how effects that are usually attributed to squirt flow under partially saturated conditions can be explained alternatively in terms of the double-porosity model. The result is therefore a theory that generalizes, but is completely consistent with, Biot’s theory of poroelasticity and is valid for analysis of elastic wave data from highly fractured reservoirs.
Direct Photon Results from CDF

Direct (prompt) photon production is a field of very high interest in hadron colliders. It provides probes to search for new phenomena and to test QCD predictions. In this article, two recent cross-section results for direct photon production using the full CDF Run II data set are presented: diphoton production and photon production in association with a heavy quark.
Estimating Discrete Joint Probability Distributions for Demographic Characteristics at the Store Level Given Store Level Marginal Distributions and a City-Wide Joint Distribution

This paper provides a solution to the problem of estimating a joint distribution using the associated marginal distributions and a related joint distribution. The particular application we have in mind is estimating joint distributions of demographic characteristics corresponding to market areas for individual retail stores. Marginal distributions are generally available at the census tract level, but joint distributions are only available for Metropolitan Statistical Areas which are generally much larger than the market for a single retail store. Joint distributions over demographics are an important input into mixed logit demand models for aggregate data. Market shares that vary systematically with demographics are essential for relieving the restrictions imposed by the Independence from Irrelevant Alternative property of the logit model.
Asymmetric acid-catalyzed Meerwein-Ponndorf-Verley-Aldol reactions of enolizable aldehydes.

A highly, stereo- and regioselective Meerwein−Ponndorf−Verley−Aldol etherification process of enolizable aldehydes is described. This new transformation is catalyzed by trifluoroacetic acid. The method also allows cross-aldol reactions with α-branched enolizable aldehydes and thus provides access to defined configured quaternary stereogenic centers.
Synthesis, structure, and characterization of two new layered mixed-metal phosphates, BaTeMO4(PO4) (M = Nb5+ or Ta5+.

Two new isostructural mixed-metal phosphates, BaTeMO4(PO4) (M = Nb5+ or Ta5+), have been synthesized as bulk phase powders and single crystals by standard solid-state techniques using BaCO3, TeO2, Nb2O5 (or Ta2O5), and NH4H2PO4 as reagents. The materials have novel layered crystal structures consisting of [M5+O6/2]- corner-sharing octahedral chains that are connected to [Te4+O4/2]0 polyhedra and [P5+O2/1O2/2]- tetrahedra. The Ba2+ cations reside between the layers and maintain charge balance. The Te4+ cations are in asymmetric coordination environments attributable to their lone pairs. The Nb5+ distorts along the local C4 direction of its octahedron resulting in a “short−long−short−long” Nb−O−Nb bond motif. The Nb5+ cation displaces away from the oxide ligands that are bonded to Te4+ or P5+ cations, attributable to the structural rigidity of the TeO4 and PO4 polyhedra. Thus, the TeO4 and PO4 polyhedra support and reinforce the intraoctahedral distortion observed within the NbO6 octahedra. Infrared and Ram...
Complementarity in wormhole chromodynamics

Abstract The electric charge of a wormhole mouth and the magnetic flux “linked” by the wormhole are non-commuting observables, and so cannot be simultaneously diagonalized. We use this observation to resolve some puzzles in wormhole electrodynamics and chromodynamics. Specifically, we analyzed the color electric field that results when a colored object traverses a wormhole, and we discuss the measurement of the wormhole charge and flux using Aharonov-Bohm interference effects.
A theory of mixing in a stably stratified fluid

A theory is developed for turbulence in a stably stratified fluid, for example in the experiments of Rouse & Dodu and of Turner where there is no shear and the turbulence is induced by a source of energy near the lower boundary of the fluid. A growing mixed layer of thickness D appears in the lower portion of the fluid and is separated from the non-turbulent fluid above, in which the buoyancy gradient is given, by an interfacial layer of thickness h. The lower mixed layer has a very weak buoyancy gradient and the large buoyancy difference across the interfacial layer is Δb.As indicated by the experiments of Thompson & Turner and Hopfinger & Toly, and derived by the author in a recent paper, if u is the root-mean-square horizontal velocity and l is the integral length scale, the eddy viscosity ul is a constant in a homogeneous fluid agitated by a grid. When there is stratification, the theory indicates that the fluid motion is unaffected by buoyancy forces in the mixed layer, so that ul should again be constant in the lower portions of the mixed layer. Since l is proportional to distance, we may conveniently suppose that the source of the disturbances is at a level z = 0 where u is infinite in accordance with uz = K. Thus we may take K to be a fundamental parameter characterizing the turbulent energy source. Then z is distance above the plane of the virtual energy source. If the non-turbulent fluid has uniform buoyancy, DΔb = U2 may be shown to be constant. In general, whether constant or not, U may be taken to be a fundamental parameter expressing the stability. The quantity is the most fundamental of the several Richardson numbers that have been introduced in this problem because, with its use, ‘constants’ of proportionality do not depend on the molecular coefficients of viscosity or diffusion (for high Reynolds number turbulence) or on the geometry of the grid.The theory contains a number of results: .h ∼ D, as observed in several experiments.
Predictive Controller and Estimator for NASA Deep Space Network Antennas

In this paper a modified state-space predictive controller is introduced, and a predictive estimator presented to complement the design of a predictive control law. This approach has been used for the design of tracking controllers for the NASA/JPL 70-m antennas. Several tracking scenarios have been tested (step input, constant rate rise and fall, raised cosine trajectory), and significant improvement of performance has been observed. A wider bandwidth and improved roll-off rate is obtained for the predictive closed-loop system in comparison with the LQ system. The predictive control system is robust to the plant parameter variations. Shifts of plant poles of 20% of their nominal values has a tracking error of the same order as for a nominal plant. Its disturbance suppression properties have also been simulated and found good for input disturbances and for the measurement noise, if the measurement noise spectrum is higher than the plant fundamental frequency. The system disturbance suppression properties can be enhanced if a disturbance filter is applied. For the predictive estimator, the estimation error and time to reach stationary error are much smaller than for the LQ estimator.
Adaptive rate-controlled scheduling for multimedia applications

We present a framework for integrated scheduling of continuous media (CM) and other applications. The framework, called ARC scheduling, consists of a rate-controlled on-line CPU scheduler, an admission control interface, a monitoring module, and a rate adaptation interface. ARC scheduling allows threads to reserve CPU time for guaranteed progress. It provides firewall protection between threads such that the progress guarantee to a thread is independent of how other threads actually make scheduling requests. Rate adaptation allows a CM application to adapt its rate to changes in its execution environment. We have implemented the framework as an extension to Solaris 2.3. We present experimental results which show that ARC scheduling is highly effective for integrated scheduling of CM and other applications in a general purpose workstation environment. ARC scheduling is a key component of an end system architecture we have designed and implemented to support networking with quality of service guarantees. In particular, it enables protocol threads to make guaranteed progress.
Macroporous nanowire nanoelectronic scaffolds for synthetic tissues

The development of three-dimensional (3D) synthetic biomaterials as structural and bioactive scaffolds is central to fields ranging from cellular biophysics to regenerative medicine. As of yet, these scaffolds cannot electrically probe the physicochemical and biological microenvironments throughout their 3D and macroporous interior, although this capability could have a marked impact in both electronics and biomaterials. Here, we address this challenge using macroporous, flexible and free-standing nanowire nanoelectronic scaffolds (nanoES), and their hybrids with synthetic or natural biomaterials. 3D macroporous nanoES mimic the structure of natural tissue scaffolds, and they were formed by self-organization of coplanar reticular networks with built-in strain and by manipulation of 2D mesh matrices. NanoES exhibited robust electronic properties and have been used alone or combined with other biomaterials as biocompatible extracellular scaffolds for 3D culture of neurons, cardiomyocytes and smooth muscle cells. Furthermore, we show the integrated sensory capability of the nanoES by real-time monitoring of the local electrical activity within 3D nanoES/cardiomyocyte constructs, the response of 3D-nanoES-based neural and cardiac tissue models to drugs, and distinct pH changes inside and outside tubular vascular smooth muscle constructs.
Air as the renewable carbon source of the future: an overview of CO2 capture from the atmosphere

The burning of our diminishing fossil fuel reserves is accompanied by a large anthropogenic CO2 release, which is outpacing nature's CO2 recycling capability, causing significant environmental harm. Much is being done to avert this crisis including more efficient technology for usage, savings and replacing carbon fuels with alternatives whenever feasible. The capture of CO2 followed by sequestration (CCS) into geologic formation or under the seas has also been proposed and in some cases implemented. Carbon capture and recycling (CCR) to fuels and materials is another promising approach. At first, capturing carbon dioxide from concentrated sources such as fossil fuel burning power plants, industrial plants and natural sources might be the most practical. However, the capture of CO2 from the atmosphere is also technically feasible despite its low concentration (∼390 ppm) and presents even some benefits compared to point source CO2 capture. The present article reviews methods developed for the capture of CO2 directly from the air as well as their advantages and drawbacks. While strong bases such as sodium hydroxide and potassium hydroxide could be used, their regeneration is energy intensive, requiring high temperatures. Amines either physically or chemically immobilized on solid supports require much lower temperatures for their regeneration and are therefore promising candidates.
Information Theoretic Bounds for Compressed Sensing

In this paper, we derive information theoretic performance bounds to sensing and reconstruction of sparse phenomena from noisy projections. We consider two settings: output noise models where the noise enters after the projection and input noise models where the noise enters before the projection. We consider two types of distortion for reconstruction: support errors and mean-squared errors. Our goal is to relate the number of measurements, m , and SNR, to signal sparsity, k, distortion level, d, and signal dimension, n . We consider support errors in a worst-case setting. We employ different variations of Fano's inequality to derive necessary conditions on the number of measurements and SNR required for exact reconstruction. To derive sufficient conditions, we develop new insights on max-likelihood analysis based on a novel superposition property. In particular, this property implies that small support errors are the dominant error events. Consequently, our ML analysis does not suffer the conservatism of the union bound and leads to a tighter analysis of max-likelihood. These results provide order-wise tight bounds. For output noise models, we show that asymptotically an SNR of ((n)) together with (k (n/k)) measurements is necessary and sufficient for exact support recovery. Furthermore, if a small fraction of support errors can be tolerated, a constant SNR turns out to be sufficient in the linear sparsity regime. In contrast for input noise models, we show that support recovery fails if the number of measurements scales as o(n(n)/SNR), implying poor compression performance for such cases. Motivated by the fact that the worst-case setup requires significantly high SNR and substantial number of measurements for input and output noise models, we consider a Bayesian setup. To derive necessary conditions, we develop novel extensions to Fano's inequality to handle continuous domains and arbitrary distortions. We then develop a new max-likelihood analysis over the set of rate distortion quantization points to characterize tradeoffs between mean-squared distortion and the number of measurements using rate-distortion theory. We show that with constant SNR the number of measurements scales linearly with the rate-distortion function of the sparse phenomena.
Airway complications after single-stage unifocalization for pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries.

Objective We analyze the incidence of postoperative severe airflow limitation after single-stage unifocalization in patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries (PA/VSD/MAPCAs) and comment on the treatment performed. Methods From 1994 until 2014, 118 patients with diagnosis of PA, VSD, MAPCAs underwent surgical treatment. Four patients (3.4%) developed severe airflow complications postoperatively. Chromosome 22q11 deletion was present in three of them. Median age at the time of unifocalization was 6.2 months (range 21 days to 11 months). Results The first patient developed malacia and compression of the left bronchus from the distal RV-PA conduit and was treated with external bronchial stenting with two incomplete costal cartilage rings. The second patient developed recurrent esophagus-left bronchus fistula treated with multiple surgical esophageal and bronchus reconstructions. The third child presented with bilateral bronchial malacia treated with bilateral stenting followed by surgical elongation of the neo-left pulmonary artery to avoid external compression. The last patient developed bilateral bronchomalacia treated with bilateral bronchial stenting followed by RV-PA conduit replacement and endobronchial stenting calibration. Conclusion Particular categories of patients with PA, VSD, MAPCAs (22q11 chromosome deletion, neonates/infants, patients with dominant/exclusive collaterals) may be more predisposed to develop airway compromise. The treatment of the lesion should be individualized according to the pathogenic mechanism. We suggest endoluminal treatment in absence of compression by vascular structures while surgery was used in case of extrinsic compression. doi: 10.1111/jocs.12539 (J Card Surg 2015;30:453–458)
Recursive subhomogeneous algebras

We introduce and characterize a particularly tractable class of unital type 1 C*-algebras with bounded dimension of irreducible representations. Algebras in this class are called recursive subhomogeneous algebras, and they have an inductive description (through iterated pullbacks) which allows one to carry over from algebras of the form many of the constructions relevant in the study of the stable rank and K-theory of simple direct limits of homogeneous C*-algebras. Our characterization implies, in particular, that if is a separable C*-algebra whose irreducible representations all have dimension at most and if for each the space of -dimensional irreducible representations has finite covering dimension, then is a recursive subhomogeneous algebra. We demonstrate the good properties of this class by proving subprojection and cancellation theorems in it. Consequences for simple direct limits of recursive subhomogeneous algebras, with applications to the transformation group C*-algebras of minimal homeomorphisms, will be given in separate papers.
A fixed point localization formula for the Fourier transform of regular semisimple coadjoint orbits

Abstract Let G R be a Lie group acting on an oriented manifold M , and let ω be an equivariantly closed form on M . If both G R and M are compact, then the integral ∫ M ω is given by the fixed point integral localization formula (Theorem 7.11 in Berline et al. Heat Kernels and Dirac Operators, Springer, Berlin, 1992). Unfortunately, this formula fails when the acting Lie group G R is not compact: there simply may not be enough fixed points present. A proposed remedy is to modify the action of G R in such a way that all fixed points are accounted for. Let G R be a real semisimple Lie group, possibly noncompact . One of the most important examples of equivariantly closed forms is the symplectic volume form dβ of a coadjoint orbit Ω . Even if Ω is not compact, the integral ∫ Ω dβ exists as a distribution on the Lie algebra g R . This distribution is called the Fourier transform of the coadjoint orbit . In this article, we will apply the localization results described in [L1,L2] to get a geometric derivation of Harish-Chandra's formula (9) for the Fourier transforms of regular semisimple coadjoint orbits. Then, we will make an explicit computation for the coadjoint orbits of elements of g R ∗ which are dual to regular semisimple elements lying in a maximally split Cartan subalgebra of g R .
Almost-natural proofs

Razborov and Rudich have proved that, under a widely-believed hypothesis about pseudorandom number generators, there do not exist P/poly-computable Boolean function properties with density greater than 2^-^p^o^l^y^(^n^) that exclude P/poly. This famous result is widely regarded as a serious barrier to proving strong lower bounds in circuit complexity theory, because virtually all Boolean function properties used in existing lower bound proofs have the stated complexity and density. In this paper, we show that under the same pseudorandomness hypothesis, there do exist nearly-linear-time-computable Boolean function properties with only slightly lower density (namely, 2^-^q^(^n^) for a quasi-polynomial function q) that not only exclude P/poly, but even separate NP from P/poly. Indeed, we introduce a simple, explicit property called discrimination that does so. We also prove unconditionally that there exist non-uniformly nearly-linear-time-computable Boolean function properties with this same density that exclude P/poly. Along the way we also note that by slightly strengthening Razborov and [email protected]?s argument, one can show that their ''naturalization barrier'' is actually a barrier to proving superquadratic circuit lower bounds, not just P/poly circuit lower bounds. It remains open whether there is a naturalization barrier to proving superlinear circuit lower bounds.
Finding Minimum Data Requirements Using Pseudo-independence

In situations where Bayesian networks (BN) inferencing approximation is allowable, we show how to reduce the amount of sensory observations necessary and in a multi-agent context the amount of agent communication. To achieve this, we introduce Pseudo-Independence, a relaxed independence relation that quantitatively differentiates the various degrees of independence among nodes in a BN. We combine Pseudo-Independence with Context-Specific Independence to obtain a measure, Context-Specific Pseudo-Independence (CSPI), that determines the amount of required data that needs to be used to infer within the error bound. We then use a Conditional Probability Table-based generation search process that utilize CSPI to determine the minimal observation set. We present empirical results to demonstrate that bounded approximate inference can be made with fewer observations.
The design of environmental regimes: Social construction, contextuality, and improvisation

While much of the literature on environmental regimes has focused on effectiveness, this article takes a new look at a lesser-studied topic, the evolution of regime design. Understanding how regimes differ in design, and how various factors and processes shape such design, is important if we are to more carefully craft these regimes. We should also pay close attention to the formative role of social construction and context. Focusing on transboundary marine programs, we see that their designs basically follow a common template, namely that of the UNEP (United Nations Environmental Programme) Regional Seas Programme. However, the action of context (i.e., local actors and political processes) can modify these designs away from the common template. The extent to which these programs begin to differentiate from each other may be an important sign of program maturity and responsiveness to context. In this article, we examine a set of transboundary marine programs to uncover what the important dimensions of differentiation are. Then, we focus on one specific program, the SSME (Sulu-Sulawesi Marine Ecoregion) and closely trace how its specific form and organization came about. The analysis is informed by a model of institutional coherence that portrays institutions as the product of multiple generative mechanisms (e.g., social construction, ecological fit, and others). While it is premature to make definite judgments about the relative merits of competing regime designs, the work provides us with a new mode of analysis that can provide helpful directions for institutional assessment.
REBUILDING AFRICA'S SCIENTIFIC CAPACITY IN FOOD AND AGRICULTURE

After 50 years of independence, Africa is still a profoundly agrarian continent where 2/3 of the people directly or indirectly derive their living from agriculture. The central question facing African governments and donor agencies today is “What can be done to transform agriculture in Africa?” The most difficult challenge facing Africa is how to borrow and generate new technology that is supported by an efficient set of core institutions that can increase agricultural productivity and reduce poverty. Building an interactive system of three core institutions – research, education and extension – has been, and will remain, a multigenerational challenge. This paper focuses on building African research capacity and graduate education in Africa in an era of globalization.
Market Structure, Internal Capital Markets, and the Boundaries of the Firm

We study how the creation of an internal capital market (an ICM) can invite strategic responses in product markets that, in turn, shape firm boundaries. ICMs provide ex post resource flexibility, but come with ex ante commitment costs. Alternatively, stand-alones possess commitment ability but lack flexibility. By creating flexibility, integration can sometimes deter a rival’s entry, but commitment problems can also invite predatory capital raising. These forces drive different organizational equilibria depending on the integrator’s relation to the product market. Hybrid organizational forms like strategic alliances can sometimes dominate integration by offering some of its benefits with fewer strategic costs. THIS PAPER DEVELOPS A THEORY of the firm in which internal capital markets affect the ability to compete in product markets. In our model, a firm’s decision to operate an internal capital market affects the fund-raising behavior of its product market rivals. An internal capital market can either scare away rival firms or else induce them to compete more aggressively, raising more capital than they otherwise would. In equilibrium, these strategic interactions determine the boundaries of the firm.
Why Religion in Politics Does Not Violate la Conception Américaine de la Laïcité

La conception Americaine de la laicite consists principally of a constitutional norm-the nonestablishment norm-and of the law that the U.S. Supreme Court has developed in the course of enforcing the norm. The nonestablishment norm forbids government-both the national government and state government-to "establish" religion. American laicite also consists of what we may call "the morality of liberal democracy." My aim in this essay is to explain why religion in politics does not violate American laicite; more specifically, my aim is to explain why political reliance on religiously grounded morality violates neither the nonestablishment norm nor the morality of liberal democracy.
THE EFFECTIVENESS OF STATE LEGISLATION IN MITIGATING MORAL HAZARD: EVIDENCE FROM AUTOMOBILE INSURANCE*

Abstract Insurance fraud, which adds an estimated $85 billion per year to the total insurance bill in the United States, is an extremely serious problem for consumers, regulators, and insurance companies. This paper analyzes the effects of state legislation and market conditions on automobile insurance fraud from 1988 to 1999, a period exhibiting a substantial increase in the enactment of antifraud legislation. Our empirical results show that the laws have mixed effects: two laws have no statistically significant effect on fraud. The strongest evidence of fraud mitigation effects is associated with mandatory special investigation units, classification of insurance fraud as a felony, and mandatory reporting of professionals to licensing authorities. However, laws requiring insurers to report potentially fraudulent claims to law enforcement authorities actually increase fraud, which may reflect some substitution from more efficacious private efforts to less productive state activity. Many underlying charact...
A simple and efficient route to N-functionalized dithieno[3,2-b:2', 3'-d]pyrroles: Fused-ring building blocks for new conjugated polymeric systems

A general synthetic route has been developed for the simple and efficient preparation of N-functionalized dithieno[3,2-b:2‘,3‘-d]pyrroles. These synthetic methods utilize N-functionalized N-(3‘-thienyl)-3-aminothiophenes produced from the Pd-catalyzed amination of 3-bromothiophene with primary amines, followed by a one-pot bromination/cyclization process. This combination allows the convenient preparation of a variety of N-functionalized dithieno[3,2-b:2‘,3‘-d]pyrroles (where substituent = hexyl, octyl, decyl, tert-butyl, and p-hexylphenyl) in good yield (65−82%). Characterization of the structure and reactivity of this class of compounds is also described, including electrochemical and photophysical data for all compounds and X-ray structural data for the octyl-, tert-butyl-, and p-hexylphenyl-functionalized compounds.
German Debt Traded in London During the Second World War: A British Perspective on Hitler

Two series of German bonds, issued in 1924 and 1930, traded on the London Stock Exchange throughout Hitler's 1933-45 regime in Germany. We isolate both structural breaks and turning points in these bond series. Major turning points follow Hider's reintroduction of conscription in 1935, the outbreak of war in 1939 and the D-Day invasion of June 1944. The German bonds' sustained downward trend after 1935 suggests that bondholders recognized the risks posed by Hitler's programme. Bond prices recovered during the war, however, and appear to have anticipated the overthrow of Hitler and the postwar settlement of foreign bondholders' claims. German bonds, even in peace time, were distinctly dubious investments, and the fact of war has entirely justified the distrust with which they have long been regarded.
Gender Transitions in Later Life: The Significance of Time in Queer Aging

Concepts of time are ubiquitous in studies of aging. This article integrates an existential perspective on time with a notion of queer time based on the experiences of older transgender persons who contemplate or pursue a gender transition in later life. Interviews were conducted with male-to-female identified persons aged 50 years or older (N = 22), along with participant observation at three national transgender conferences (N = 170 hr). Interpretive analyses suggest that an awareness of “time left to live” and a feeling of “time served” play a significant role in later life development and help expand gerontological perspectives on time and queer aging.
The Alternating Sign Matrix Polytope

We define the alternating sign matrix polytope as the convex hull of $n\times n$ alternating sign matrices and prove its equivalent description in terms of inequalities. This is analogous to the well known result of Birkhoff and von Neumann that the convex hull of the permutation matrices equals the set of all nonnegative doubly stochastic matrices. We count the facets and vertices of the alternating sign matrix polytope and describe its projection to the permutohedron as well as give a complete characterization of its face lattice in terms of modified square ice configurations. Furthermore we prove that the dimension of any face can be easily determined from this characterization.
BPS Bound States Of D0-D6 And D0-D8 Systems In A B-Field

The D0-D6 system, which is not supersymmetric in the absence of a Neveu-Schwarz B-field, becomes supersymmetric if a suitable constant B-field is turned on. On one side of the supersymmetric locus, this system has a BPS bound state, and on the other side it does not. After compactification on Bbb T6, this gives a simple example in which the number of 1/8 BPS states jumps as the moduli of the compactification are changed. The D0-D8 system in a B-field has two different supersymmetric loci, only one of which is continuously connected to the familiar supersymmetric D0-D8 system without a B-field. In a certain range, the D0-D8 system also has a BPS bound state. In the limit in which the B-field goes to infinity, supersymmetric D0-D6 and D0-D8 systems and their bound states can be studied using non-commutative Yang-Mills theory.
A Structured Framework for Assessing the "Goodness" of Agile Methods

Agile Methods are designed for customization, they offer an organization or a team the flexibility to adopt a set of principles and practices based on their culture and values. While that flexibility is consistent with the agile philosophy, it can lead to the adoption of principles and practices that can be sub-optimal relative to the desired objectives. We question then, how can one determine if adopted practices are "in sync" with the identified principles, and to what extent those principles support organizational objectives? In this research, we focus on assessing the "goodness" of an agile method adopted by an organization based on (1) its adequacy, (2) the capability of the organization to provide the supporting environment to successfully implement the method, and (3) the method's effectiveness. To guide our assessment, we propose the Objectives, Principles and Practices (OPP) framework. The design of the OPP framework revolves around the identification of the agile objectives, principles that support the achievement of those objectives, and practices that reflect the "spirit" of those principles. Well-defined linkages between the objectives and principles, and between the principles and practices are also established to support the assessment process. We assess the adequacy of an agile method by traversing the linkages in a top-down fashion. That is, given the set of objectives espoused by the agile method, we follow the linkages downward to ensure that the appropriate principles are enunciated, and that the proper practices are expressed. We assess the capability of an organization to implement its adopted method and the effectiveness of that implementation by using both a top-down and bottom-up traversal of the linkages. The bottom-up assessment, however, is predicated on the identification of people, process, project and product properties associated with each practice that attest to the presence and implementation of that practice. We refer to each practice, property pair as an indicator. By following the linkages upward from the indicators, we can infer the use of proper principles and the achievement of desired objectives.
Probing mechanical properties of graphene with Raman spectroscopy

The use of Raman scattering techniques to study the mechanical properties of graphene films is reviewed here. The determination of Gruneisen parameters of suspended graphene sheets under uni- and bi-axial strain is discussed, and the values are compared to theoretical predictions. The effects of the graphene−substrate interaction on strain and to the temperature evolution of the graphene Raman spectra are discussed. Finally, the relation between mechanical and thermal properties is presented along with the characterization of thermal properties of graphene with Raman spectroscopy.
A flow-guided file layout for out-of-core streamline computation

We present a file layout algorithm for flow fields to improve runtime I/O efficiency for out-of-core streamline computation. Because of the increasing discrepancy between the speed of processors and storage devices, the cost of I/O becomes a major bottleneck for out-of-core computation. To reduce the I/O cost, loading data with better spatial locality has proved to be effective. It is also known that sequential file access is more efficient. To facilitate efficient streamline computation, we propose to reorganize the data blocks in a file following the data access pattern so that more efficient I/O and effective prefetching can be accomplished. To achieve the goal, we divide the domain into small spatial blocks and order the blocks into a linear layout based on the underlying flow directions. The ordering is done using a weighted directed graph model which can be formulated as a linear graph arrangement problem. Our goal is to arrange the file in a way consistent with the data access pattern during streamline computation. This allows us to prefetch a contiguous segment of data at a time from disk and minimize the memory cache miss rate. We use a recursive partitioning method to approximate the optimal layout. Our experimental results show that the resulting file layout reduces I/O cost and hence enables more efficient out-of-core streamline computation.
Performance of various computers using standard linear equations software in a Fortran environment

This note compares the performance of different computer systems while solving dense systems of linear equations using the LINPACK software in a Fortran environment. About 100 com puters, ranging from a CRAY X-MP to the 68000-based systems such as the Apollo and SUN Workstations to IBM PC's, are compared.
Tetris is hard, even to approximate

In the popular computer game of Tetris, the player is given a sequence of tetromino pieces and must pack them into a rectangular gameboard initially occupied by a given configuration of filled squares; any completely filled row of the gameboard is cleared and all pieces above it drop by one row. We prove that in the offline version of Tetris, it is NP-complete to maximize the number of cleared rows, maximize the number of tetrises (quadruples of rows simultaneously filled and cleared), minimize the maximum height of an occupied square, or maximize the number of pieces placed before the game ends. We furthermore show the extreme inapproximability of the first and last of these objectives to within a factor of p1-Ɛ, when given a sequence of p pieces, and the inapproximability of the third objective to within a factor of 2-Ɛ, for any Ɛ > 0. Our results hold under several variations on the rules of Tetris, including different models of rotation, limitations on player agility, and restricted piecesets.
Optical trapping with high forces reveals unexpected behaviors of prion fibrils.

Amyloid fibrils feature in many human diseases and in epigenetic memory, but understanding their molecular structure has been difficult. Now, through a combination of optical trapping and fluorescent imaging to examine amyloid fibrils of the yeast prion protein Sup35, the unexpected unfolding of individual subdomains has been detected, suggesting strong noncovalent interactions maintain the fibril even if individual monomers unfold.
Social Media, Knowledge Sharing, and Innovation: Toward a Theory of Communication Visibility

This paper offers a theory of communication visibility based on a field study of the implementation of a new enterprise social networking site in a large financial services organization. The emerging theory suggests that once invisible communication occurring between others in the organization becomes visible for third parties, those third parties could improve their metaknowledge i.e., knowledge of who knows what and who knows whom. Communication visibility, in this case made possible by the enterprise social networking site, leads to enhanced awareness of who knows what and whom through two interrelated mechanisms: message transparency and network translucence. Seeing the contents of other's messages helps third-party observers make inferences about coworkers' knowledge. Tangentially, seeing the structure of coworkers' communication networks helps third-party observers make inferences about those with whom coworkers regularly communicate. The emerging theory further suggests that enhanced metaknowledge can lead to more innovative products and services and less knowledge duplication if employees learn to work in new ways. By learning vicariously rather than through experience, workers can more effectively recombine existing ideas into new ideas and avoid duplicating work. Moreover, they can begin to proactively aggregate information perceived daily rather than engaging in reactive search after confronting a problem. I discuss the important implications of this emerging theory of communication visibility for work in the knowledge economy.
Metabolic syndrome components and their response to lifestyle and metformin interventions are associated with differences in diabetes risk in persons with impaired glucose tolerance

Aims: To determine the association of metabolic syndrome (MetS) and its components with diabetes risk in participants with impaired glucose tolerance (IGT), and whether intervention-related changes in MetS lead to differences in diabetes incidence. Methods: We used the National Cholesterol Education Program/Adult Treatment Panel III (NCEP/ATP III) revised MetS definition at baseline and intervention-related changes of its components to predict incident diabetes using Cox models in 3234 Diabetes Prevention Program (DPP) participants with IGT over an average follow-up of 3.2 years. Results: In an intention-to-treat analysis, the demographic-adjusted hazard ratios (95% confidence interval) for diabetes in those with MetS (vs. no MetS) at baseline were 1.7 (1.3–2.3), 1.7 (1.2–2.3) and 2.0 (1.3–3.0) for placebo, metformin and lifestyle groups, respectively. Higher levels of fasting plasma glucose and triglycerides at baseline were independently associated with increased risk of diabetes. Greater waist circumference (WC) was associated with higher risk in placebo and lifestyle groups, but not in the metformin group. In a multivariate model, favourable changes in WC (placebo and lifestyle) and high-density lipoprotein cholesterol (placebo and metformin) contributed to reduced diabetes risk. Conclusions: MetS and some of its components are associated with increased diabetes incidence in persons with IGT in a manner that differed according to DPP intervention. After hyperglycaemia, the most predictive factors for diabetes were baseline hypertriglyceridaemia and both baseline and lifestyle-associated changes in WC. Targeting these cardiometabolic risk factors may help to assess the benefits of interventions
Charge and spin fractionalization in strongly correlated topological insulators

We construct an effective topological Landau-Ginzburg theory that describes general SU(2) incompressible quantum liquids of strongly correlated particles in two spatial dimensions. This theory characterizes the fractionalization of quasiparticle quantum numbers and statistics in relation to the topological ground-state symmetries, and generalizes the Chern-Simons, BF ('background field') and hierarchical effective gauge theories to an arbitrary representation of the SU(2) symmetry group. We mainly focus on fractional topological insulators with time-reversal symmetry, which are treated as SU(2) generalizations of the quantum Hall effect.
The microfabrication of capacitive ultrasonic transducers

Surface-micromachined capacitive ultrasonic transducers, which are suitable for operation in both air and water, have been fabricated and tested. Amorphous silicon is used as a sacrificial layer because of its good etching selectivity versus a nitride membrane, and improved cell-size control is obtained by lithographic definition of cavity walls. In addition, appropriate feature designs based on two-dimensional (2-D) process simulations make it possible to achieve device cavity sealing with g-line optical lithography. Transmission experiments in both water and air are presented. A dynamic range in excess of 110 dB is observed in air at 2.3 MHz. In water, a single pair of transducers is able to operate from 2 to 15 MHz. When tuned, a 3.5-MHz tone burst results in a received signal with better than 60-dB signal-to-noise ratio (SNR). The transducer behaviour agrees with a theoretical understanding of transducer dynamics. The dynamic ranges achieved in this paper are the best reported to date for surface-micromachined capacitive ultrasonic transducers.
Structure Preserving Approximations of Conservative Forces for Application to Small-Body Dynamics

Approximation-based methods, such as the cubetree algorithm, have proven to be significantly faster than traditional methods for complex force evaluations near small irregular bodies. Such methods also hold the promise of simplifying the inclusion of experimental data to update the force model. However, the cubetree algorithm does not preserve intrinsic properties of the gravitational force such as continuity, divergence freedom, or exactness. These properties may be needed for trajectory optimization, for the use of geometric (e.g., symplectic) integrators for long-term propagation, and for other trajectory design problems. This paper presents several adaptive schemes preserving global continuity, exactness, or divergence freedom, and discusses the difficulties involved in preserving all of these properties globally.
Drift-Diffusion in Mangled Worlds Quantum Mechanics

In Everett9s many-worlds interpretation, where quantum measurements are seen as decoherence events, inexact decoherence may let large worlds mangle the memories of observers in small worlds, creating a cutoff in observable world measure. I solve a growth–drift–diffusion–absorption model of such a mangled worlds scenario, and show that it reproduces the Born probability rule closely, though not exactly. Thus, inexact decoherence may allow the Born rule to be derived in a many-worlds approach via world counting, using a finite number of worlds and no new fundamental physics.