cssi/SciSciGPT-SciSciNet huggingface dataset:
A sunspot paradox

Abstract This paper shows that the local stability properties of dynamic general equilibrium macroeconomic models may depend on the length of a period in the model economy. This leads to the following paradoxical situation: The economy may be driven by sunspots for some decision frequencies, while sunspots can have no impact at other decision frequencies.
As if Kyoto mattered: The clean development mechanism and transportation

Abstract Transportation is a major source of greenhouse gas (GHG) emissions and the most rapidly growing anthropogenic source. In the future, the developing world will account for the largest share of transport GHG increases. Four basic components drive transportation energy consumption and GHG emissions: activities (A), mode share (S), fuel intensity (I) and fuel choice (F) (ASIF). Currently, the Kyoto Protocol's clean development mechanism (CDM) serves as the main international market-based tool designed to reduce GHG emissions from the developing world. Theoretically, the CDM has the dual purpose of helping developing countries achieve “sustainable development” goals and industrialized countries meet their Kyoto emissions reduction commitments. This paper reviews overall CDM activities and transportation CDM activities to date and then presents findings from three case studies of transportation CDM possibilities examined with the ASIF framework in Santiago de Chile. The analysis suggests that bus technology switch (I) provides a fairly good project fit for the CDM, while options aimed at inducing mode share (S) to bicycle, or modifying travel demand via land use changes (ASI) face considerable challenges. The implications of the findings for the CDM and the “post-Kyoto” world are discussed.
Water channel formation and ion transport in linear and branched lipid bilayers

Using molecular dynamics simulations, we studied the influence of methyl chain branching on transmembrane potential induced formation of water channels in lipid bilayers and ion transport. We compared the response of a bilayer lipid that has multiple methyl branches diphytanoylphosphatidylcholine (DPhPC) with its straight-chain counterpart dipalmitoylphosphatidylcholine (DPPC) to a transmembrane potential created by an imbalance in ionic charges across the membrane. We found that, compared to the straight-chain DPPC lipid bilayer membranes, branched DPhPC lipid membranes require a higher critical transmembrane potential to break down, followed by water channel formation, and transport of anions and cations through the pore. We demonstrated that the bulkiness of the added methyl branches leads to “barrel-stave” pores in DPhPC membranes which require a higher transmembrane potential to produce than the toroidal pores produced in the straight chain DPPC lipid bilayers. Our results provided a deeper understanding of the water channel formation and ion transport through lipid bilayer membrane and might help explain the increased resistance to charge-induced poration in organisms with membranes abundant in branched lipids.
CO2 Exsolution – challenges and Opportunities in Subsurface Flow Management

Abstract This paper summarizes the results of a 4-year study regarding the implications of CO 2 exsolution on geological carbon storage security and subsurface flow management, including core-flood experiments, micro-model studies, pore-scale modeling, and relative permeability calculations. When separate phase CO 2 exsolves from carbonated water in sandstones, water relative permeability drops significantly. The relative permeability of exsolved CO 2 is disproportionately reduced compared to drainage due to the dispersed morphology of exsolved CO 2 bubbles in the pore space. Our studies suggest that CO 2 exsolution provides an opportunity for mobility control in subsurface processes. The low mobility of exsolved CO 2 suggests that risks of groundwater contamination due to this phenomenon are small.
Matrix strings in weakly curved background fields

Abstract We investigate further the recent proposal for the form of the Matrix theory action in weak background fields. We perform DVV reduction to the multiple D0-brane action in order to find the Matrix string theory action for multiple fundamental strings in curved but weak NSNS and RR backgrounds. This matrix sigma model gives a definite prescription on how to deal with RR fields with an explicit spacetime dependence in Type II string theory. We do this both via the 9–11 flip and the chain of T and S dualities, and further check on their equivalence explicitly. In order to do so, we also discuss the implementation of S-duality in the operators of the 2-dimensional worldvolume supersymmetric gauge theory describing the Type IIB D-string. We compare the result to the known Green–Schwarz sigma model action (for one string), and use this comparison in order to discuss about possible, non-linear background curvature corrections to the Matrix string action (involving many strings), and therefore to the Matrix theory action. We illustrate the nonabelian character of our action with an example involving multiple fundamental strings in a nontrivial RR flux, where the strings are polarized into a noncommutative configuration. This corresponds to a dielectric type of effect on fundamental strings.
Metastable electrical characteristics of polycrystalline thin-film photovoltaic modules upon exposure and stabilization

The significant features of a series of stabilization experiments conducted at the National Renewable Energy Laboratory (NREL) between May 2009 and the present are reported. These experiments evaluated a procedure to stabilize the measured performance of thin-film polycrystalline cadmium telluride (CdTe) and copper indium gallium diselenide (CIGS) thin-film photovoltaic (PV) modules. The current-voltage (I-V) characteristics of CdTe and CIGS thin-film PV devices and modules exhibit transitory changes in electrical performance after thermal exposure in the dark and/or bias and light exposures. We present the results of our case studies of module performance versus exposure: light soaked at 65°C; exposed in the dark under forward bias at 65°C; and, finally, longer-term outdoor exposure. We find that stabilization can be achieved to varying degrees using either light-soaking or dark-bias methods and that the existing IEC 61646 light-soaking interval may be appropriate for CdTe and CIGS modules with one caveat: it is likely that at least three exposure intervals are required for stabilization.
Spin Meissner effect in superconductors and the origin of the Meissner effect

We propose a dynamical explanation of the Meissner effect in superconductors and predict the existence of a spin Meissner effect: that a macroscopic spin current flows within a London penetration depth λL of the surface of superconductors in the absence of applied external fields, with carrier density = the superfluid density and carrier speed (me= bare electron mass). The two members of a Cooper pair circulate in orbits of radius 2λL in opposite direction and the spin current in a Cooper pair has orbital angular momentum . Our description also provides a "geometric" interpretation of the difference between type-I and type-II superconductors.
Quantum Nyquist temperature fluctuations

Using the Nyquist approach, temperature fluctuations of an object, in thermal contact with a reservoir, are studied. We argue that, upon decreasing the size of the object, one necessarily reaches the quantum regime. The crossover temperature between the classical and quantum regimes is given by T∗∼ℏ/kBτ, where τ is the thermal relaxation time of the system. For a nano-scale metallic particle in a good thermal contact with a reservoir, T∗ can be on a scale of a few Kelvin.
Measuring welfare gains from better quality infrastructure

Projects and reforms targeting infrastructure services can affect consumer welfare through changes in the price, coverage, or quality of the services provided. The benefits of improved service quality-while significant-are often overlooked because they are difficult to quantify. This paper reviews methods of evaluating the welfare implications of changes in the quality of infrastructure services within the broader theoretical perspective of welfare measurement. The study outlines the theoretical assumptions and data requirements involved, illustrating each method with examples that highlight common methodological features and differences. The paper also presents the theoretical underpinnings and potential applications of a new approach to analyzing the effects of interruptions in the supply of infrastructure services on household welfare.
Testing for structural change in conditional models

In the past decade, we have seen the development of a new set of tests for structural change of unknown timing in regression models, most notably the SupF statistic of Andrews (1993, Econometrica 61, 825}856), the ExpF and AveF statistics of AndrewsPloberger (1994, Econometrica 62, 1383}1414), and the ‚ statistic of Nyblom (1989, Journal of American Statistical Association 84, 223}230). The distribution theory used for these tests is primarily asymptotic, and has been derived under the maintained assumption that the regressors are stationary. This excludes structural change in the marginal distribution of the regressors. As a result, these tests technically cannot discriminate between structural change in the conditional and marginal distributions. This paper attempts to remedy this de"ciency by deriving the large sample distributions of the test statistics allowing for structural change in the marginal distribution of the regressors. We "nd that the asymptotic distributions of the SupF, ExpF, AveF and ‚ statistics are not invariant to structural change in the regressors. To solve the size problem, we introduce a &"xed regressor bootstrap’ which achieves the "rst-order asymptotic distribution, and appears to possess reasonable size properties in small samples. Our bootstrap theory allows for arbitrary structural change in the regressors, including structural shifts, polynomial trends, and exogenous stochastic trends. It allows for lagged dependent variables and heteroskedastic error processes. ( 2000 Elsevier Science S.A. All rights reserved.
The Effects of Client Identity Strength and Professional Identity Salience on Auditor Judgments

ABSTRACT: Considerable recent audit regulation, both proposed and mandated, and accounting research has focused on auditor independence threats arising over long auditor tenure. Psychology research, however, suggests independence threats also likely arise when auditor tenure is short because auditors can quickly develop a strong client identity, raising questions about the effectiveness of mandatory audit partner or firm rotation to address independence concerns. Relying on Social Identity Theory, I examine mechanisms for promoting auditor independence that can be implemented regardless of auditor tenure or rotation. I conduct two experiments in a setting with no prior auditor-client history. As predicted, auditors who identify more strongly with their clients, by sharing their values, agree more with the client's preferred accounting treatment, unless the salience or arousal of their professional identity is heightened. Further, as predicted, heightening professional identity salience increases professio...
Methylation: Its role in the environmental mobility of heavy elements

Formation of bonds between methyl groups and heavy elements (metals or metalloids) alters various physical properties such as solubility or volatility. This alteration enhances the mobility of the heavy metal and can play a major role in the environmental cycles for these elements. Environmental methylation has been established as a major factor in the environmental movement of mercury and arsenic, and very probably affects other elements similarly. Two methylating agents (methylcobalamin and methyl iodide) have been found to mobilize metals out of water-insoluble compounds and/or anoxic sediments. These two compounds react with quite different substrates, but the kinetics of the resulting dissolutions follow virtually identical patterns. These reactions proceed through formation of a methylated intermediate on the substrate surface, followed by movement of the heavy element out of the solid lattice into the surrounding solution.
Synthesis of the Thioborate Crystal ZnxBa2B2S5+x (x ≈ 0.2) for Second Order Nonlinear Optical Applications

Thioborate materials have been considered for novel infrared nonlinear optical (NLO) materials having large optical nonlinear properties combined with favorable laser damage thresholds and wide transmission ranges from the visible to the mid-infrared regions. In this work, known and new thioborate materials have been investigated that have the potential to overcome the low laser damage thresholds of the NLO chalcopyrite sulfide materials such as AgGaS2 without losing their large nonlinear properties and wide transmission ranges. A new thioborate phase, polycrystalline ZnxBa2B2S5+x (x ≈ 0.2), has been prepared by the reaction of the metal sulfides and B2S3 glass in carbon crucibles sealed inside evacuated silica tubes. It crystallizes in the tetragonal system with unit cell parameters of a = 4.762(4) A and c = 24.020(7) A and is based on isolated (BS3)3- structural units. The second harmonic generation (SHG) efficiency determined on powders of ZnxBa2B2S5+x (x ≈ 0.2) is ∼50 times larger than that of α-SiO2....
Implications of Channel Structure for Leasing or Selling Durable Goods

In spite of the fact that many durable products are sold through dealers, the literature has largely ignored the issue of how product durability affects the interactions between a manufacturer and her dealers. We seek to fill this gap by considering a durable goods manufacturer that uses independent dealers to get her product to consumers. In contrast to much of the literature, we specifically consider the possibility that if the manufacturer sells her product, then the dealers can either sell or lease it to the final consumer. One of our more interesting findings is that, when the level of competition among dealers is high, the manufacturer prefers to use a lease-brokering arrangement in which the dealers earn a margin for brokering leases between the manufacturer and end consumers, instead of selling her product to the dealers. This complements existing results that show that when suppliers of durable goods interact directly with consumers, selling is the dominant strategy for high levels of competitive intensity.
Simultaneous Matting and Compositing

Recent work in matting, hole filling, and compositing allows image elements to be mixed in a new composite image. Previous algorithms for matting foreground elements have assumed that the new background for compositing is unknown. We show that, if the new background is known, the matting algorithm has more freedom to create a successful matte by simultaneously optimizing the matting and compositing operations. We propose a new algorithm, that integrates matting and compositing into a single optimization process. The system is able to compose foreground elements onto a new background more efficiently and with less artifacts compared with previous approaches. In our examples, we show how one can enlarge the foreground while maintaining the wide angle view of the background. We also demonstrate composing a foreground element on top of similar backgrounds to help remove unwanted portions of the background or to re-scale or re-arrange the composite. We compare and contrast our method with a number of previous matting and compositing systems.
Dynamic Inefficiencies in an Employment-Based Health Insurance System: Theory and Evidence †

We investigate the effects of the institutional settings of the US health care system on individuals' life-cycle medical expenditures. Health is a form of general human capital; labor turnover and labor-market frictions prevent an employer-employee pair from capturing the entire surplus from investment in an employee's health. Thus, the pair underinvests in health during working years, thereby increasing medical expenditures during retirement. We provide empirical evidence consistent with the comparative statics predictions of our model using the Medical Expenditure Panel Survey (MEPS) and the Health and Retirement Study (HRS). Our estimates suggest significant inefficiencies in health investment in the United States.
A Servant of Two Masters: Communication and the Selection of International Bureaucrats

International bureaucrats must often serve multiple principals who collectively choose policy. How does this affect bureaucrats' incentives to truthfully reveal their private information? I construct a cheap talk model in which a bureaucrat possesses private information about how policies translate into outcomes. The bureaucrat can communicate publicly observable messages about this information to two policymakers, who must then bargain over a set of policy choices. I find that both the bureaucrat's willingness to communicate informatively and the choice of an optimal bureaucrat are highly contingent on the bargaining powers of the two policymakers. When each policymaker is bound to adhere to the bargaining outcome, “moderate” bureaucrats are most preferred. In contrast, when at least one policymaker can leave the bargaining table and exercise an outside option, “biased” bureaucrats can be optimal. I illustrate my findings by examining UN weapons inspections in Iraq from 1991 to 2003.I wish to thank Bruce Bueno de Mesquita, Michael Gilligan, Catherine Hafer, Matias Iaryczower, Dimitri Landa, Adam Meirowitz, Alastair Smith, and the editor and two anonymous reviewers for their feedback. Previous drafts of this article were presented in the New York University Politics Department Research Workshop and the 2006 Annual Conference of the Midwest Political Science Association.
GEOMETRIC ALGORITHMS FOR THE CONSTRAINED 1-D K-MEANS CLUSTERING PROBLEMS AND IMRT APPLICATIONS

In this paper, we present efficient geometric algorithms for the discrete constrained 1-D K-means clustering problem and extend our solutions to the continuous version of the problem. One key clustering constraint we consider is that the maximum difference in each cluster cannot be larger than a given threshold. These constrained 1-D K-means clustering problems appear in various applications, especially in intensity-modulated radiation therapy (IMRT). Our algorithms improve the efficiency and accuracy of the heuristic approaches used in clinical IMRT treatment planning.
One‐dimensional models of quasi‐neutral parallel electric fields

Parallel electric fields can exist in the magnetic mirror geometry of auroral field lines if they conform to the quasineutral equilibrium solutions. Results on quasi-neutral equilibria and on double layer discontinuities were reviewed and the effects on such equilibria due to non-unique solutions, potential barriers and field aligned current flows using as inputs monoenergetic isotropic distribution functions were examined.
A Concise and Versatile Double‐Cyclization Strategy for the Highly Stereoselective Synthesis and Arylative Dimerization of Aspidosperma Alkaloids

The monoterpene indole alkaloids represent the largest family of alkaloid natural products whose more than 2,000 members display a broad range of chemical diversity and potent biological activity.1 The structural challenges presented by this family have long been a source of interest, resulting in the development of a variety of inventive synthetic strategies to access various family members. The biogenetically related natural alkaloids N-methylaspidospermidine (1), N-methylquebrachamine (2), and tabernaebovine (3) represent the aspidosperma subfamily of monoterpene indole alkaloids (Figure 1).2-5 The dimeric alkaloid 3, isolated from Tabernaemontana bovina in 1998,2e has a fascinating molecular constitution that exhibits a unique C2–C15′ linkage between two pentacyclic aspidosperma skeletons. While elegant strategies for synthesis of other dimeric monoterpene indole alkaloids have been reported,5 no synthetic solution to the distinctive C2–C15′ union present in 3 exists. As an outgrowth of our laboratory's studies concerning electrophilic amide activation,6 we report a concise and convergent strategy for the enantioselective synthesis of alkaloids (–)-1, (+)-2, and dimeric (+)-dideepoxytabernaebovine (4).
Annotation of bacterial and archaeal genomes: improving accuracy and consistency.

ly, annotating a genome amounts to attaching information to support use of the genome. This includes an almost endless variety of types of analysis and attachment of interpretations. In our experience, it has proven useful to prioritize the analyses, and the following items provide at least a reasonable working notion of what is meant: 1. Genes are identified. This effort includes at least protein-encoding genes and some of the RNA-encoding genes (often just tRNAs and rRNAs). 2. The functions of genes are predicted. 3. Metabolic reconstructions are developed and tied to the specific genes. 4. Prophages, insertion sequences, and transposons are labeled. 5. Frameshifts and pseudogenes are predicted. 6. Regulatory sites and operons are identified as a step toward developing an inventory of regulons. In practice, usually only the locations of genes and their predicted functions are provided by the initial annotation effort. Accordingly the first part of this review deals with the status of gene identification in prokaryotes, and the second part deals with the task of predicting the function to be associated with protein-coding genes. 2. Gene Prediction in Bacteria and Archaea Once the sequence of a prokaryotic genome has been determined, the next step is the definition of the functional Figure 1. Growth of available genomes and SwissProt annotations. While the primary sequence repository (GenBank1) doubles in size every 18 months, high-quality annotations (we take SwissProt2 as an example) cannot keep up with this growth. The graph compares the growth on a logarithmic scale. Figure 2. How annotations are done. This diagram is intended to convey the interactions between the different types of activities that make up the annotation process (blue). A key point is that maintenance and improvement of annotations originate in expert analysis and are reflected through protein family curation, since the “curate genomes” activity is seldom done. Annotation of Bacterial and Archaeal Genomes Chemical Reviews, 2007, Vol. 107, No. 8 3433
Finishing flows quickly with preemptive scheduling

Today's data centers face extreme challenges in providing low latency. However, fair sharing, a principle commonly adopted in current congestion control protocols, is far from optimal for satisfying latency requirements.We propose Preemptive Distributed Quick (PDQ) flow scheduling, a protocol designed to complete flows quickly and meet flow deadlines. PDQ enables flow preemption to approximate a range of scheduling disciplines. For example, PDQ can emulate a shortest job first algorithm to give priority to the short flows by pausing the contending flows. PDQ borrows ideas from centralized scheduling disciplines and implements them in a fully distributed manner, making it scalable to today's data centers. Further, we develop a multipath version of PDQ to exploit path diversity.Through extensive packet-level and flow-level simulation, we demonstrate that PDQ significantly outperforms TCP, RCP and D3 in data center environments. We further show that PDQ is stable, resilient to packet loss, and preserves nearly all its performance gains even given inaccurate flow information.
Corotational Instability, Magnetic Resonances and Global Inertial-Acoustic Oscillations in Magnetized Black-Hole Accretion Discs

Low-order, non-axisymmetric p-modes (also referred as inertial-acoustic modes) in hydrodynamic accretion discs around black holes are plausible candidates for high- frequency quasi-periodic oscillations (QPOs) observed in a number of accreting black- hole systems. These modes are trapped in the inner-most region of the accretion disc, and are subject to global instabilities due to wave absorption at the corotation reso- nance (where the wave pattern frequency !=m equals the disc rotation rate ), when the fluid vortensity, � = � 2 =(2�) (whereandare the radial epicyclic frequency and disc surface density, respectively), has a positive gradient. We investigate the effects of disc magnetic fields on the wave absorption at corotation and the related wave super-reflection of the corotation barrier, and on the overstability of disc p- modes. In general, in the presence of magnetic fields, the p-modes have the character of inertial-fast magnetosonic waves in their propagation zone. For discs with a pure toroidal field, the corotation resonance is split into two magnetic resonances, where the wave frequency in the corotating frame of the fluid, ˜ ! = ! m, matches the slow magnetosonic wave frequency. Significant wave energy/angular momentum absorption occurs at both magnetic resonances, but with opposite signs, such that one of them enhances the super-reflection while the other diminishes it. The combined effect of the two magnetic resonances is to reduce the super-reflection and the growth rate of the overstable p-modes. Our calculations show that even a subthermal toroidal field (with the magnetic pressure less than the gas pressure) may suppress the overstabil- ity of hydrodynamic (B = 0) p-modes. For accretion discs with mixed (toroidal and vertical) magnetic fields, two additional Alfven resonances appear, where ˜ ! matches the local Alfven wave frequency. The effect of these additional resonances is to fur- ther reduce or diminish the growth rate of p-modes. Our results suggest that in order for the non-axisymmetric p-modes to be a viable candidate for the observed high- frequency QPOs, the disc magnetic field must be appreciably subthermal, or other mode excitation mechanisms are at work.
Migration selectivity and the effects of public programs

Abstract A model of the spatial distribution of mobile heterogeneous agents is formulated to assess how a price change or program subsidy that is location-specific affects the composition of local residents via selective migration and thus biases evaluations of the effectiveness of the program based on its local consequences. Longitudinal data from Colombia are used to test the implications of migration selectivity. The findings confirm the existence of selective migration, suggesting that local subsidies to human capital attract high-income but, within income groups, low-fertility households and those with low human capital endowments. These migration patterns are shown to be consistent with the dominance of endowment over tastes heterogeneity in the population under plausible behavioral assumptions.
Credit Risk and the Term Structure of Lease Rates: A Reduced Form Approach

Previous research either assumes default free leases or leases subject to default risk using a structural approach. However, structural credit risk models suffer from a common criticism that the firm’s asset value process is unobservable. We develop a reduced form credit risk model for leases that avoids making assumptions regarding unobservable asset valuation processes. Furthermore, we assume a correlated market and credit risk that provides us with a simple analytic formula for valuing defaultable lease contracts. Numerical analysis reveals that tenant credit risk can have a substantial impact on the term structure of leases. Finally, we use the model to demonstrate the implied lease term structure for a set of retail and financial firms in the Fall of 2000.
Sociotropic Politics: The American Case

American elections depend substantially on the vitality of the national economy. Prosperity benefits candidates for the House of Representatives from the incumbent party (defined as the party that controls the presidency at the time of the election), whereas economic downturns enhance the electoral fortunes of opposition candidates. Short-term fluctuations in economic conditions also appear to affect the electorate's presidential choice, as well as the level of public approval conferred upon the president during his term. By this evidence, the political consequences of macroeconomic conditions are both pervasive and powerful. But just how do citizens know whether the incumbent party has succeeded or failed? What kinds of economic evidence do people weigh in their political appraisals? The purpose of our paper is to examine two contrasting depictions of individual citizens – one emphasizing the political significance of citizens' own economic predicaments, the other stressing the political importance of citizens' assessments of the nation's economic predicament - that might underlie the aggregate entwining of economics and politics. Ours is an inquiry into the political economy of individual citizens.
Accurate Prediction of Phase Transitions in Compressed Sensing via a Connection to Minimax Denoising

Compressed sensing posits that, within limits, one can undersample a sparse signal and yet reconstruct it accurately. Knowing the precise limits to such undersampling is important both for theory and practice. We present a formula that characterizes the allowed undersampling of generalized sparse objects. The formula applies to approximate message passing (AMP) algorithms for compressed sensing, which are here generalized to employ denoising operators besides the traditional scalar soft thresholding denoiser. This paper gives several examples including scalar denoisers not derived from convex penalization-the firm shrinkage nonlinearity and the minimax nonlinearity-and also nonscalar denoisers-block thresholding, monotone regression, and total variation minimization. Let the variables e = k/N and δ = n/N denote the generalized sparsity and undersampling fractions for sampling the k-generalized-sparse N-vector x0 according to y=Ax0. Here, A is an n×N measurement matrix whose entries are iid standard Gaussian. The formula states that the phase transition curve δ = δ(e) separating successful from unsuccessful reconstruction of x0 by AMP is given by δ = M(e|Denoiser) where M(e|Denoiser) denotes the per-coordinate minimax mean squared error (MSE) of the specified, optimally tuned denoiser in the directly observed problem y = x + z. In short, the phase transition of a noiseless undersampling problem is identical to the minimax MSE in a denoising problem. We prove that this formula follows from state evolution and present numerical results validating it in a wide range of settings. The above formula generates numerous new insights, both in the scalar and in the nonscalar cases.
Transgression or Stasis? Challenging Foucault in LIS Theory

Michel Foucault (1926–84) is a primary thinker informing the construction of a critical theory of library and information science (LIS), or librarianship. He is widely cited and is adapted in various ways that focus on LIS forms of power, discourse, and so on. Others have addressed Foucault’s topics, but he remains central. Librarianship has taken up a prior challenge to more fully explore his work, and it is now time to carefully review the implications of Foucault’s thinking as a foundation for a critical‐theoretical LIS. Foucault has undergone extensive analysis and critique, and this article is a similar step within LIS. While not comprehensive, a review of Foucauldian ideas within LIS literature from a core group of authors is undertaken. Critiques and problems in Foucault’s thinking are reviewed since, by relying on Foucault’s insights for a line of analysis and research, this LIS theoretical work will reflect some of those same problems.
Asymmetric Effects of Positive and Negative Money-Supply Shocks

This paper examines whether positive and negative money-supply shocks have symmetric effects on output. The results are consistent with the hypothesis that positive money-supply shocks do not have an effect on output, while negative money-supply shocks do have an effect on output. This finding is independent of whether or not expected money is assumed to affect output. The results reported in this paper imply that the Fed could increase the growth rate of real output by reducing the standard deviation of unexpected changes in the money supply.
Palladium-Catalyzed Suzuki–Miyaura Cross-Coupling Using Phosphinous Acids and Dialkyl(chloro)phosphane Ligands

The use of eleven palladium complexes having monomeric and μ-chloro-bridged dimeric structures and either bulky dialkyl- and diarylphosphinous acid ligands (POPd, POPd-Br, POPd1, POPd2, POPd6, POPd7, Ph1-Phoxide) or dialkyl(chloro)phosphane ligands (PXPd, PXPd2, PXPd6, PXPd7) for Suzuki–Miyaura coupling reactions has been evaluated. Screening and optimization of catalyst loading, solvent, temperature, and base showed that excellent results can be obtained with electron-deficient and electron-rich aryl iodides, bromides, and chlorides in the presence of 2.5 mol-% of palladium–phosphinous acid POPd, (tBu2POH)2PdCl2, in 1,4-dioxane using cesium carbonate as base. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Timing-sync protocol for sensor networks

Wireless ad-hoc sensor networks have emerged as an interesting and important research area in the last few years. The applications envisioned for such networks require collaborative execution of a distributed task amongst a large set of sensor nodes. This is realized by exchanging messages that are time-stamped using the local clocks on the nodes. Therefore, time synchronization becomes an indispensable piece of infrastructure in such systems. For years, protocols such as NTP have kept the clocks of networked systems in perfect synchrony. However, this new class of networks has a large density of nodes and very limited energy resource at every node; this leads to scalability requirements while limiting the resources that can be used to achieve them. A new approach to time synchronization is needed for sensor networks.In this paper, we present Timing-sync Protocol for Sensor Networks (TPSN) that aims at providing network-wide time synchronization in a sensor network. The algorithm works in two steps. In the first step, a hierarchical structure is established in the network and then a pair wise synchronization is performed along the edges of this structure to establish a global timescale throughout the network. Eventually all nodes in the network synchronize their clocks to a reference node. We implement our algorithm on Berkeley motes and show that it can synchronize a pair of neighboring motes to an average accuracy of less than 20ms. We argue that TPSN roughly gives a 2x better performance as compared to Reference Broadcast Synchronization (RBS) and verify this by implementing RBS on motes. We also show the performance of TPSN over small multihop networks of motes and use simulations to verify its accuracy over large-scale networks. We show that the synchronization accuracy does not degrade significantly with the increase in number of nodes being deployed, making TPSN completely scalable.
Progressive decline in circulating CNP with aging is associated with progressive cardiac fibrosis and myocardial impairment

Background Cardiac aging is associated with altered myocardial structure and function that may contribute to the development of heart failure (HF), particularly in the elderly. C-type natriuretic peptide (CNP) is of endothelial cell origin and represents the most potent anti-fibrotic peptide of the natriuretic peptide (NP) family. CNP activates the NP receptor-B (NPR-B), which is found in high abundance in cardiac fibroblasts. Further, selective cardiac knockout of NPR-B contributes to exaggerated cardiomyocyte hypertrophy in response to pressure overload. In addition, infusion of CNP suppresses post-myocardial infarction (MI) induced cardiac fibrosis in a rodent model of MI. The impact of aging on circulating CNP and associated left ventricular (LV) structure and function are undefined.
Making All the Children Above Average: Ethical and Regulatory Concerns for Pediatricians in Pediatric Enhancement Research

Building on the knowledge generated by the long history of disease-oriented research, the next few decades will witness an explosion of biomedical enhancements to make people faster, stronger, smarter, less forgetful, happier, prettier, and live longer. Growing interest in pediatric enhancements is likely to stimulate the conduct of enhancement research involving children. However, guidelines for the protection of human subjects were developed for investigations of therapeutic modalities. To date, virtually no attention has been paid to whether these rules would be appropriate for investigations to establish the safety and efficacy of technologies intended for enhancement rather than therapeutic uses and, if not, whether ethically acceptable rules could be designed. This article discusses whether the current guidelines for pediatric research provide appropriate protections for pediatric subjects in enhancement research and considers what additional protections might be necessary.
Lomonosov’s theorem cannot be extended to chains of four operators

We show that the celebrated Lomonosov theorem cannot be improved by increasing the number of commuting operators. Specifically, we prove that if T : '1 ! '1 is the operator without a non-trivial closed invariant subspace constructed by C. J. Read, then there are three operators S1, S2 and K (non-multiples of the identity) such that T commutes with S1, S1 commutes with S2, S2 commutes with K, and K is compact. It is also shown that the commutant of T contains only series of T. All Banach spaces in this note are assumed to be infinite dimensional and separable; all operators are linear and bounded. We say that an operator is a non-scalar operator if it is not a multiple of the identity operator. One of the major results in the history of the Invariant Subspace Problem was obtained by V. Lomonosov in (L) who proved that if an operator T on a Banach space commutes with another non-scalar operator S and S commutes with a non-zero compact operator K, then T has an invariant subspace. Motivated by their study of the Invariant Subspace Problem for positive operators on Banach lattices, Y. A. Abramovich and C. D. Aliprantis have asked recently whether or not Lomonosov's theorem can be extended to chains of four or more operators. The purpose of this note is to answer this question in the negative. For our initial operator T we will take an operator without an invariant subspace on '1
Superacid-Promoted Hydroxyalkylation of 1,2-Indandiones

1,2-Indandione reacts efficiently with arenes to give 2,2-diaryl-1-indanones by the hydroxyalkylation reaction. The Bronsted superacid CF3SO3H (triflic acid) is an effective catalyst for these condensation reactions. The requisite 1,2-indandiones were prepared from the 1-indanones.
The Distribution of Stars and Stellar Remnants at the Galactic Center

Motivated by recent observations that suggest a low density of old stars around the Milky Way supermassive black hole (SMBH), models for the nuclear star cluster are considered that have not yet reached a steady state under the influence of gravitational encounters. A core of initial radius 1-1.5 pc evolves to a size of approximately 0.5 pc after 10 Gyr, roughly the size of the observed core. The absence of a Bahcall-Wolf cusp is naturally explained in these models, without the need for fine-tuning or implausible initial conditions. In the absence of a cusp, the time for a 10 M ☉ black hole (BH) to spiral in to the Galactic center from an initial distance of 5 pc can be much greater than 10 Gyr. Assuming that the stellar BHs had the same phase-space distribution initially as the stars, their density after 5-10 Gyr is predicted to rise very steeply going into the stellar core, but could remain substantially below the densities inferred from steady-state models that include a steep density cusp in the stars. Possible mechanisms for the creation of the parsec-scale initial core include destruction of stars on centrophilic orbits in a pre-existing triaxial nucleus, inhibited star formation near the SMBH, or ejection of stars by a massive binary. The implications of these models are discussed for the rates of gravitational-wave inspiral events, as well as other physical processes that depend on a high density of stars or stellar-mass BHs near SgrA*.
Eigenvalues of Hermite and Laguerre ensembles: large beta asymptotics

Abstract In this paper we examine the zero and first order eigenvalue fluctuations for the β-Hermite and β-Laguerre ensembles, using tridiagonal matrix models, in the limit as β → ∞ . We prove that the fluctuations are described by multivariate Gaussians of covariance O ( 1 / β ) , centered at the roots of a corresponding Hermite (Laguerre) polynomial. The covariance matrix itself is expressed as combinations of Hermite or Laguerre polynomials respectively. We show that the approximations are of real value even for small β; we can use them to approximate the true functions even for the traditional β = 1 , 2 , 4 values.
Real-time monitoring of video quality in IP networks

This paper investigates the problem of assessing the quality of video transmitted over IP networks. Our goal is to develop a methodology that is both reasonably accurate and simple enough to support the large-scale deployments that the increasing use of video over IP are likely to demand. For that purpose, we focus on developing an approach that is capable of mapping network statistics, e.g., packet losses, available from simple measurements, to the quality of video sequences reconstructed by receivers. A first step in that direction is a loss-distortion model that accounts for the impact of network losses on video quality, as a function of application-specific parameters such as video codec, loss recovery technique, coded bit rate, packetization, video characteristics, etc. The model, although accurate, is poorly suited to large-scale, on-line monitoring, because of its dependency on parameters that are difficult to estimate in real-time. As a result, we introduce a ldquorelative qualityrdquo metric (rPSNR) that bypasses this problem by measuring video quality against a quality benchmark that the network is expected to provide. The approach offers a lightweight video quality monitoring solution that is suitable for large-scale deployments. We assess its feasibility and accuracy through extensive simulations and experiments.
Cost impact of automated acceptance testing of electrical ground support equipment for spacecraft testing

In today's environment, building a reliable and cost effective spacecraft is perhaps emphasized more than ever before. Sponsors are looking for the same high quality products but at lower costs and with shorter schedules. Whether it is a spacecraft for the Department of Defense (DoD), a research observatory for the National Aeronautics and Space Administration (NASA), or a commercial communications satellite, total cost is a significant factor.
Polygonal chains cannot lock in 4D

We prove that, in all dimensions d⩾4, every simple open polygonal chain and every tree may be straightened, and every simple closed polygonal chain may be convexified. These reconfigurations can be achieved by algorithms that use polynomial time in the number of vertices, and result in a polynomial number of “moves”. These results contrast to those known for d=2, where trees can “lock”, and for d=3, where open and closed chains can lock.
The efficiency of voluntary incentive policies for preventing biodiversity loss

Habitat loss is a primary cause of loss of biodiversity but conserving habitat for species presents challenges. Land parcels differ in their ability to produce returns for landowners and landowners may have private information about the value of the land to them. Land parcels also differ in the type and quality of habitat and the spatial pattern of land use across multiple landowners is important for determining the conservation value of parcels. This paper analyzes the relative efficiency of simple voluntary incentive-based policies in achieving biodiversity conservation objectives. This topic is important not just for biodiversity conservation but for any effort to provide a public good requiring coordination across multiple decision-makers who have some degree of private information. We develop a method that integrates spatially explicit data, an econometric model of private land-use decisions, landscape simulations, a biological model of biodiversity as a function of landscape pattern, and an algorithm that estimates the set of efficient solutions. These methods allow us to simulate landowner responses to policies, measure the consequences of these decisions for biodiversity conservation, and compare these outcomes to efficient outcomes to show the relative efficiency of various policy approaches. We find substantial differences in biodiversity conservation scores generated by simple voluntary incentive-based policies and efficient solutions. The performance of incentive-based policies is particularly poor at low levels of the conservation budget where spatial fragmentation of conserved parcels is a large concern. Performance can be improved by encouraging agglomeration of conserved habitat and by incorporating basic biological information, such as that on rare habitats, into the selection criteria.
1,2,5,6-tetraketopyracene: Synthesis, and structure by ab initio calculation and x-ray analysis

Abstract The title compound is conveniently synthesized from the known 1,2-diketopyracene via NBS bromination followed by reaction with silver nitrate in acetonitrile, and treatment with sodium acetate trihydrate in DMSO. Its structure determined by semiempirical PM3 and ab initio calculations is in excellent agreement with the x-ray analysis, and suggests that the bond alternation observed in pyracylene and related compounds is probably not due to antiaromaticity.
Equivalent Relaxations of Optimal Power Flow

Several convex relaxations of the optimal power flow (OPF) problem have recently been developed using both bus injection models and branch flow models. In this paper, we prove relations among three convex relaxations: a semidefinite relaxation that computes a full matrix, a chordal relaxation based on a chordal extension of the network graph, and a second-order cone relaxation that computes the smallest partial matrix. We prove a bijection between the feasible sets of the OPF in the bus injection model and the branch flow model, establishing the equivalence of these two models and their second-order cone relaxations. Our results imply that, for radial networks, all these relaxations are equivalent and one should always solve the second-order cone relaxation. For mesh networks, the semidefinite relaxation and the chordal relaxation are equally tight and both are strictly tighter than the second-order cone relaxation. Therefore, for mesh networks, one should either solve the chordal relaxation or the SOCP relaxation, trading off tightness and the required computational effort. Simulations are used to illustrate these results.
In Praise of Vagueness: Malleability of Vague Information as a Performance Booster

Is the eternal quest for precise information always worthwhile? Our research suggests that, at times, vagueness has its merits. Previous research has demonstrated that people prefer precise information over vague information because it gives them a sense of security and makes their environments more predictable. However, we show that the fuzzy boundaries afforded by vague information can actually help individuals perform better than can precise information. We document these findings across two laboratory studies and one quasi–field study that involved different performance-related contexts (mental acuity, physical strength, and weight loss). We argue that the malleability of vague information allows people to interpret it in the manner they desire, so that they can generate positive response expectancies and, thereby, perform better. The rigidity of precise information discourages desirable interpretations. Hence, on certain occasions, precise information is not as helpful as vague information in boostin...