cssi/SciSciGPT-SciSciNet huggingface dataset:
Long-term forecasting of Internet backbone traffic

We introduce a methodology to predict when and where link additions/upgrades have to take place in an Internet protocol (IP) backbone network. Using simple network management protocol (SNMP) statistics, collected continuously since 1999, we compute aggregate demand between any two adjacent points of presence (PoPs) and look at its evolution at time scales larger than 1 h. We show that IP backbone traffic exhibits visible long term trends, strong periodicities, and variability at multiple time scales. Our methodology relies on the wavelet multiresolution analysis (MRA) and linear time series models. Using wavelet MRA, we smooth the collected measurements until we identify the overall long-term trend. The fluctuations around the obtained trend are further analyzed at multiple time scales. We show that the largest amount of variability in the original signal is due to its fluctuations at the 12-h time scale. We model inter-PoP aggregate demand as a multiple linear regression model, consisting of the two identified components. We show that this model accounts for 98% of the total energy in the original signal, while explaining 90% of its variance. Weekly approximations of those components can be accurately modeled with low-order autoregressive integrated moving average (ARIMA) models. We show that forecasting the long term trend and the fluctuations of the traffic at the 12-h time scale yields accurate estimates for at least 6 months in the future.
Inverse Methods in Physical Oceanography

Preface 1. Finite-dimensional inverse theory 2. The smoothing of observations 3. Data assimilation 4. The spatial structure of the Kalman filter 5. Generalized inverses of dynamical models 6. Antenna analysis 7. Nonlinear quasi-geostrophic models 8. Open-ocean modeling: quasi-geostrophy 9. Primitive-equation models 10. Outstanding problems Bibliography Subject index.
Syntax encodes information structure: Evidence from on-line reading comprehension

Abstract Although sentences are thought to be generally easier to process when given information precedes new information, closer examination reveals that these preferences only manifest within some syntactic structures. Here, we examine the consequences of the relative ordering of given and new information (information structure) for the on-line comprehension of prepositional-object (PO) and double-object (DO) dative sentences. Experiment 1 demonstrated using self-paced reading that the on-line comprehension of DO structures, but not PO structures, is more difficult with new-before-given information structure. Experiment 2 assessed the comprehension of dative sentences with animate themes to evaluate two potential sources of this interaction: information-structural constraints encoded within syntactic representations (argument structure hypothesis) vs. word-to-word contingency statistics (linear position hypothesis). Despite experiment-wise differences in word-to-word contingency statistics, the interaction between syntactic structure and information structure persisted in Experiment 2. Taken together, these results suggest that syntactic representations can include information-structural constraints on their arguments.
STEALTH GALAXIES IN THE HALO OF THE MILKY WAY

We predict that there is a population of low-luminosity dwarf galaxies orbiting within the halo of the Milky Way that have surface brightnesses low enough to have escaped detection in star-count surveys. The overall count of stealth galaxies is sensitive to the presence (or lack) of a low-mass threshold in galaxy formation. These systems have luminosities and stellar velocity dispersions that are similar to those of known ultrafaint dwarf galaxies but they have more extended stellar distributions (half light radii greater than about 100 pc) because they inhabit dark subhalos that are slightly less massive than their higher surface brightness counterparts. As a result, the typical peak surface brightness is fainter than 30 mag per square arcsec. One implication is that the inferred common mass scale for Milky Way dwarfs may be an artifact of selection bias. If there is no sharp threshold in galaxy formation at low halo mass, then ultrafaint galaxies like Segue 1 represent the high-mass, early forming tail of a much larger population of objects that could number in the hundreds and have typical peak circular velocities of about 8 kms −1 and masses within 300 pc of about 5 million solar masses. Alternatively, if we impose a low-mass threshold in galaxy formation in order to explain the unexpectedly high densities of the ultrafaint dwarfs, then we expect only a handful of stealth galaxies in the halo of the Milky Way. A complete census of these objects will require deeper sky surveys, 30m-class follow-up telescopes, and more refined methods to identify extended, self-bound groupings of stars in the halo. Subject headings: cosmology: theory — dark matter — galaxies: formation — galaxies: halos — methods: N-body simulations
PREDICTING OLDER AGE MORTALITY TRENDS

Improving early prenatal and postnatal conditions account for at least 16% to 17% of the decline in ten-year mortality rates of 60–79-year-olds between 1900 and 1960–1980. Historical trends in early prenatal and postnatal conditions imply that while the baby-boom cohort may be particularly long-lived compared to past cohorts, mortality rates may not fall as steeply for the cohorts born after 1955 as for earlier cohorts. (JEL: J15, N31)
The ratchet principle in a principal agent game with unknown costs: an experimental analysis

Abstract This paper tests for ratcheting in a dynamic principal–agent game where the principal does not have complete information. In such situations the principal often uses any information revealed by the agent's actions to extract the latter's informational rent in future periods – the “ratchet principle”. This in turn induces the agent to underproduce in order to avoid more demanding schedules in the future. We find little evidence of ratcheting. Agents play the game in a naive fashion and reveal their types even when such revelation is not optimal and the principal often does not exploit such type revelation.
State Government Revenue Recovery from the Great Recession

The “Great Recession” wreaked havoc on the revenues of state governments. In this article, we use various indicators to measure how the revenues of different state governments have—or have not—recovered in the aftermath of the Great Recession. Importantly, we also attempt to explain why these different patterns of revenue recovery have emerged. Overall, we find that some, but far from all, state governments have recovered the revenue they lost during the Great Recession. We also find that there is no single causal explanation for recovery that applies to all state governments.
A least square kernel machine with box constraints

In this paper, we present a least square kernel machine with box constraints (LSKMBC). The existing least square machines assume Gaussian hyperpriors and subsequently express the optima of the regularized squared loss as a set of linear equations. The generalized LASSO framework deviates from the assumption of Gaussian hyperpriors and employs a more general Huber loss function. In our approach, we consider uniform priors and obtain the loss functional for a given margin considered to be a model selection parameter. The framework not only differs from the existing least square kernel machines, but also it does not require Mercer condition satisfiability. Experimentally we validate the performance of the classifier and show that it is able to outperform SVM and LSSVM on certain real-life datasets.
Eigenmodes of χ (2) wave mixings: cross-induced second-order nonlinear refraction

Eigenmodes of three-wave interactions in second-order [χ(2)] nonlinear materials are explored that have a no-energy-exchange property between all the waves. They are shown to exhibit cross-induced nonlinear refraction and to be ideal candidates for amplitude-dependent phase control in χ(2) materials that emulate nonlinear refractive-index effects in third-order [χ(3)] materials. It is shown that all these eigenmodes are spatially stable.
Functional Hemodynamic Monitoring

Functional hemodynamic monitoring is the assessment of the dynamic interactions of hemodynamic variables in response to a defined perturbation. Recent interest in functional hemodynamic monitoring for the bedside assessment of cardiovascular insufficiency has heightened with the documentation of its accuracy in predicting volume responsiveness using a wide variety of monitoring devices, both invasive and noninvasive, and across multiple patient groups and clinical conditions. However, volume responsiveness, though important, reflects only part of the overall spectrum of functional physiologic variables that can be measured to define the physiologic state and monitor response to therapy.
Measurement Error in Earnings Data in the Health and Retirement Study

We provide new evidence on the extent of measurement error in respondentreported earnings data by exploiting detailed W-2 records matched to older workers in the Health and Retirement Study (HRS). Our empirical findings are qualitatively consistent with the findings of previous studies. Mean measurement error in the 1991 HRS earnings data for men is somewhat larger than what has been found in other validation studies, but is still modest, averaging about 0.059 log points, approximately 5.9 percent, or $1,500. For women in 1991, it is 0.067 log points, approximately 6.7 percent, or $916. We find a negative correlation between the measurement error and the true value of earnings as measured by the W-2 records, which indicates the presence of non-classical measurement error. For men and women, this error shows little correlation with a standard set of cross-sectional earnings determinants. The one exception is that the measurement error rises with reported education. The bias on the OLS parameter estimate of the impact of having a college degree or higher (relative to a high school drop-out) from using the respondent-reported rather than the W-2 earnings is positive and estimated to be 0.071 log points, or roughly a bias of 7 percent.
Theories of the Fractional Quantum Hall Effect

This is an introduction to the microscopic theories of the FQHE. After a brief description of experiments, trial wavefunctions and the physics they contain are discussed. This is followed by a description of the hamiltonian approach, wherein one goes from the electrons to the composite fermions by a series of transformations. The theory is then compared to other theoretical approaches and to experiment.
J-Honeypot: a Java-based network deception tool with monitoring and intrusion detection

In this paper, we describe the development of J-Honeypot, a Java-based network deception tool with a Web-based monitoring interface and a rule-based intrusion detection engine. Our J-Honeypot is based on the Honeyd program by Niels Provos, but features important enhancements. First, since J-Honeypot is written in Java, it can potentially run on various platforms, Windows or UNIX, workstations or handheld devices. Second, J-Honeypot has a rule-based intrusion detection engine, whose design is guided by the analysis of real world attack data. The attack data was collected by opening up our J-Honeypot to solicit possible attacks. Third, J-Honeypot includes a Web-based monitoring tool that is easily accessible and can help network administrators better understand network traffic and possible attacks.
An Enantioselective Approach to the Taxanes: Direct access to functionalized cis‐tricyclo[9.3.1.03,8]pentadecanes via α‐hydroxy ketone and Wagner‐Meerwein rearrangements

The feasibility of the titled reactions for the rapid, enantioselective synthesis of cis-tricyclo[9.3.1.03,8]pentadecane precursors to taxusin and taxol has been examined. The catalysts most well suited to inducing the appropriate 1,2-shifts have been identified. To a great extent, the rearrangement products are formed as a direct consequence of appropriate structural features (kinetic phenomenon) and strain minimization (thermodynamic driving force). Complementary MM2 calculations of the global minimum in each series provided indications that were completely in line with the experimental observations. Sophisticated NMR studies and X-ray crystallographic determinations were coordinated to remove any ambiguity of product structure and solid-state conformation.
An Analysis of the Relative Power Characteristics of Analytical Procedures

The overall objective of this study is to analyze the relative effectiveness and efficiency of several analytical procedures. To accomplish this, we test the power characteristics of analytical procedures in simulated business and economic environments. The analytical procedures we test include the Martingale, Census X‐11, ARIMA, and stepwise regression expectation models. The power characteristics are measured by both positive and negative testing approaches, with and without accompanying tests of details, and with simple and dispersed error seeding patterns. The results suggest that the stepwise regression model outperforms X‐11, ARIMA, and Martingale models in discriminating between the decision risks at zero and material error for both testing approaches. All models seem to perform better in terms of the aggregate slope for higher degrees of economic stability. The stepwise procedure either outperforms the other procedures for the positive approach or comes close to doing so for the negative approach ...
Statistical electromagnetic propagation and scattering in random media and rough surfaces

Summary form only given. During the past century, major advances have been made in statistical electromagnetic theory and applications in imaging and remote sensing of objects in geophysical and biological media, medical optics, ultrasound imaging, object detection, characterization of composite materials, and wireless communications. This paper discusses several areas of research starting with historical highlights and covering some of the most recent developments.
Pay Secrecy and the Gender Wage Gap in the United States

Legislators and advocates claim that pay secrecy perpetuates the gender wage gap and that the Fair Labor Standards Act (FLSA) should be amended to outlaw these practices. Using a difference-in-differences fixed-effects human-capital wage regression, I find that women with higher education levels who live in states that have outlawed pay secrecy have higher earnings, and that the wage gap is consequently reduced. State bans on pay secrecy and federal legislation to amend the FLSA to allow workers to share information about their wages may improve the gender wage gap, especially among women with college or graduate degrees
Central Limit Theorem for Linear Eigenvalue Statistics of Elliptic Random Matrices

We consider a class of elliptic random matrices which generalize two classical ensembles from random matrix theory: Wigner matrices and random matrices with iid entries. In particular, we establish a central limit theorem for linear eigenvalue statistics of real elliptic random matrices under the assumption that the test functions are analytic. As a corollary, we extend the results of Rider and Silverstein (Ann Probab 34(6):2118–2143, 2006) to real iid random matrices.
Stability margins of nonlinear optimal regulators with nonquadratic performance criteria involving cross-weighting terms ☆

Abstract In this paper we derive guaranteed gain, sector, and disk margins for nonlinear optimal and inverse optimal regulators that minimize a nonlinear-nonquadratic performance criterion involving cross-weighting terms. Specifically, sufficient conditions that guarantee gain, sector, and disk margins are given in terms of the state, control, and cross-weighting nonlinear-nonquadratic weighting functions. The proposed results provide a generalization of the “meaningful” inverse optimal nonlinear regulator stability margins as well as the classical linear-quadratic optimal regulator gain and phase margins.
Magnetism, Electron Paramagnetic Resonance, Electrochemistry, and Mass Spectrometry of the Pentacopper(II)-Substituted Tungstosilicate [Cu5(OH)4(H2O)2(A-α-SiW9O33)2]10-, A Model Five-Spin Frustrated Cluster

The dimeric, pentacopper(II)-substituted tungstosilicate [Cu5(OH)4(H2O)2(A-α-SiW9O33)2]10- (1) has been characterized by single-crystal X-ray diffraction, elemental analysis, IR, electrochemistry, magnetic measurements, electron paramagnetic resonance (EPR), and mass spectrometry (MS). Magnetization and high-field EPR measurements reveal that the pentameric copper core {Cu5(OH)4(H2O)2}6+ of 1 exhibits strong antiferromagnetic interactions (Ja = −51 ± 6 cm-1, Jb = −104 ± 1 cm-1, and Jc = −55 ± 3 cm-1) resulting in a spin ST = 1/2 ground state. EPR data show that the unpaired electron spin density is localized on the spin-frustrated apical Cu2+ ion with gzz = 2.4073 ± 0.0005, gyy = 2.0672 ± 0.0005, gxx = 2.0240 ± 0.0005, and Azz = −340 ± 20 MHz (−0.0113 cm-1). 1 can therefore be considered as a model system for a five-spin, electronically coupled, spin-frustrated system. Polyanion 1, which is stable over a wide pH domain (pH 1−7), was characterized by cyclic voltammetry (CV) in a pH 5 medium. Its CV was con...
Principles of genetic circuit design

Cells are able to navigate environments, communicate, and build complex patterns by initiating gene expression in response to specific signals. Engineers need to harness this capability to program cells to perform tasks or build chemicals and materials that match the complexity seen in nature. This review describes new tools that aid the construction of genetic circuits. We show how circuit dynamics can be influenced by the choice of regulators and changed with expression “tuning knobs.” We collate the failure modes encountered when assembling circuits, quantify their impact on performance, and review mitigation efforts. Finally, we discuss the constraints that arise from operating within a living cell. Collectively, better tools, well-characterized parts, and a comprehensive understanding of how to compose circuits are leading to a breakthrough in the ability to program living cells for advanced applications, from living therapeutics to the atomic manufacturing of functional materials.
Fast identification of state-space models via exploitation of displacement structure

The computational burden of state-space model identification has prevented its real-time application, although it offers some important advantages over other methods based on input/output transfer functions. A recently proposed state-space identification method uses ideas from sensor array signal processing to somewhat reduce the computational burden. The major costs still remain because of the need for the singular value (or sometimes QR) decomposition, which requires O(MN/sup 2/) hops and O(N/sup 2/) storage when the data matrix has size M/spl times/N, N>M. It turns out that proper exploitation, using results from the theory of displacement structure, of the Toeplitz-like nature of several matrices arising in the procedure reduces the computational effort to O(MN) flops with O(M/sup 2/+N) storage. Further computational gains are made by using the recently developed fast subspace decomposition methods. Results of the study of an actual system are described. >
Spontaneous segregation of self-propelled particles with different motilities

We study mixtures of self-propelled and passive rod-like particles in two dimensions using Brownian dynamics simulations. The simulations demonstrate that the two species spontaneously segregate to generate a rich array of dynamical domain structures whose properties depend on the propulsion velocity, density, and composition. In addition to presenting phase diagrams as a function of the system parameters, we investigate the mechanisms driving segregation. We show that the difference in collision frequencies between self-propelled and passive rods provides a driving force for segregation, which is amplified by the tendency of the self-propelled rods to swarm or cluster. Finally, both self-propelled and passive rods exhibit giant number fluctuations for sufficient propulsion velocities.
High-Dimensional Graphical Model Selection: Tractable Graph Families and Necessary Conditions

We consider the problem of Ising and Gaussian graphical model selection given n i.i.d. samples from the model. We propose an efficient threshold-based algorithm for structure estimation based on conditional mutual information thresholding. This simple local algorithm requires only low-order statistics of the data and decides whether two nodes are neighbors in the unknown graph. We identify graph families for which the proposed algorithm has low sample and computational complexities. Under some transparent assumptions, we establish that the proposed algorithm is structurally consistent (or sparsistent) when the number of samples scales as n = Ω(J-1min log p), where p is the number of nodes and Jmin is the minimum edge potential. We also develop novel non-asymptotic techniques for obtaining necessary conditions for graphical model selection.
Singularities, swallowtails and Dirac points. An analysis for families of Hamiltonians and applications to wire networks, especially the Gyroid

Abstract Motivated by the Double Gyroid nanowire network we develop methods to detect Dirac points and classify level crossings, aka. singularities in the spectrum of a family of Hamiltonians. The approach we use is singularity theory. Using this language, we obtain a characterization of Dirac points and also show that the branching behavior of the level crossings is given by an unfolding of A n type singularities. Which type of singularity occurs can be read off a characteristic region inside the miniversal unfolding of an A k singularity. We then apply these methods in the setting of families of graph Hamiltonians, such as those for wire networks. In the particular case of the Double Gyroid we analytically classify its singularities and show that it has Dirac points. This indicates that nanowire systems of this type should have very special physical properties.
Serum lactates correlate with mortality after operations for complex congenital heart disease.

Abstract Background . The objective of this study was to determine whether serum lactate levels predict mortality in children less than 1 year of age who have undergone cardiopulmonary bypass and operations for complex congenital heart disease. Methods . The initial lactate, maximum lactate, and lactate levels at 4 to 6 hours after operation were analyzed for each of 48 children less than 12 months of age who underwent cardiopulmonary bypass. Results . Data were analyzed for the 6 patients who died and the 42 patients who survived. For the patients who died, the initial postoperative serum lactate, maximum lactate, and 4- to 6-hour lactate levels were significantly higher than those in the patients who survived. All patients with an initial lactate less than 7 mmol/L, a maximum lactate less than 9 mmol/L, or a 4- to 6-hour lactate level less than 4 mmol/L survived to hospital discharge. Conclusions . Serum lactate levels may be a useful predictor of mortality in children less than 1 year of age who have undergone cardiopulmonary bypass. An elevation in serum lactate level after a complex operation for congenital heart disease should be taken as a serious indicator of potential mortality.
Lattices of minimum covolume in Chevalley groups over local fields of positive characteristic

In this article, we show that if G is a simply connected Chevalley group of either classical type of rank bigger than 1 or type E6, and q > 9 is a power of a prime number p > 5, then G = G(Fq((t 1 ))), up to an automorphism, has a unique lattice of minimum covolume, which is G(Fq[t]). 1
A general-purpose software measurement tool

A software measurement tool designed for the users of PRIME, an interactive system being developed, is presented. The tool, called SMT, allows its user to instrument a program, modify a pre-existing instrumentation and specify how the collected data are to be reduced by typing in a few simple commands. The user can also write his own measurement routines, which specify the actions to be taken at event detection time, and submit them to the SMT; after checking their correctness, the SMT deals with them as with its built-in, standard measurement routines. The design goals of a general-purpose tool like the SMT are discussed, and the prototype version of the tool, which has been implemented, is described from the two distinct viewpoints of a user and of a measurement-tool designer. An example of the application of the prototype to a measurement problem is illustrated, the reasons why not all of the design goals have been achieved in the implementation of the prototype are reviewed, and some of the foreseeable extensions of the SMT are described.
Some New Developments in the Synthesis, Functionalization, and Utilization of Monodisperse Colloidal Spheres

This article provides an overview of some recent developments related to the synthesis and functionalization of monodisperse colloidal spheres, a class of colloidal materials that has found widespread use in applications such as the fabrication of photonic crystals, optical sensing, and drug delivery. Traditionally, the choice of materials has been limited to polystyrene and silica. We and other groups have recently expanded the scope of materials by developing a number of methods for producing monodisperse colloidal spheres from various semiconductors and metals. This article is confined to our own work; it covers three different synthetic strategies: the bottom–up approach, the top–down approach, and template-directed synthesis. The colloidal spheres may have a solid, hollow, or core–shell structure, and the chemical compositions can include Se, Bi, Pb, In, Sn, Cd, Pt, Ag2Se, CdSe, PbS, or TiO2. As an example to illustrate the attractive features of these colloidal spheres, we demonstrate the fabrication of Ag2Se-based photonic crystals whose stop bands can be thermally switched between two spectral positions.
An Experimental Analysis of Compliance Behavior in Emissions Trading Programs: Some Preliminary Results

While there is a substantial body of economic theory about compliance and enforcement in emissions trading programs, and readily available information about how existing emissions trading programs are enforced, there are no empirical analyses of the determinants of compliance decisions in emissions trading programs. This paper contains preliminary results from laboratory experiments designed to examine compliance behavior in emissions trading programs.
Environmental levies and distortionary taxation:: Pigou, taxation and pollution

I note an important distinction between the optimal price of environmental quality in a second-best world and the optimal level of environmental quality. Using an analytical general equilibrium model, I show that for reasonable parameter values, an increase in tax distortions (arising from an increase in required tax revenues) leads to a fall in the optimal Pigouvian tax rate even while environmental quality improves. In general, knowledge of the direction of changes in optimal environmental tax rates due to changes in the economy is not sufficient for understanding the impact on environmental quality.  2003 Elsevier Science B.V. All rights reserved.
On a notion of maps between orbifolds I. Function spaces

This is the first of a series of papers which is devoted to a comprehensive theory of maps between orbifolds. In this paper, we define the maps in the more general context of orbispaces, and establish several basic results concerning the topological structure of the space of such maps. In particular, we show that the space of such maps of Cr class between smooth orbifolds has a natural Banach orbifold structure if the domain of the map is compact, generalizing the corresponding result in the manifold case. Motivations and applications of the theory come from string theory and the theory of pseudoholomorphic curves in symplectic orbifolds.
Modified Rayleigh conjecture and applications

Modified Rayleigh conjecture (MRC) in scattering theory is proposed and justified. MRC allows one to develop numerical algorithms for solving direct scattering problems related to acoustic wave scattering by soft and hard obstacles of arbitrary shapes. It gives an error estimate for solving the direct scattering problem. It suggests a numerical method for finding the shape of a star-shaped obstacle from the scattering data.
Teaching Adults to Read Better and Faster : Results from an Experiment in Burkina Faso

Two cognitively oriented methods were tested in Burkina Faso to help illiterates learn to read more efficiently. These were (a) speeded reading of increasingly larger word units and (b) phonological awareness training to help connect letters to speech. Learners were given reading tests and a computerized reaction time test. Although the literacy courses were shortened by the arrival of rains and government delays, the piloted methods helped adults read better than those in the standard "control" classes. Learners enrolled in the experimental classes performed better on the outcome tests than did learners enrolled in control classes. Ninety percent of the possible comparisons between treatment classes and control classes favored classes receiving treatments, and 72 percent of the measurements in favor of treatments were statistically significant. The evidence suggests that phonological awareness training is particularly effective in situations where the training period was short, and that rapid reading was more advantageous in longer training situations. Overall, the results are indicative of the potential that scientifically backed methods have in making adult literacy instruction more effective. However, due to the short duration of the classes (3-4 months) learners apparently did not receive sufficient practice to consolidate skills. Literacy skills may still be prone to being forgotten if readers do not learn to read automatically and if opportunities to read are few. This paper - a product of the Sector and Thematic Evaluation Division, Operations Evaluation Department - is part of a larger effort in the department to assess the effectiveness of adult literacy.
Workplace Aggression as a Consequence of Negative Performance Feedback.

Providing negative feedback to subordinates is one of the most difficult and stressful interactions in the workplace. Although such encounters may produce necessary changes and improved subordinate...
Unconscious Repressed Memory Is Scientifically Questionable

Psychological Science http://pss.sagepub.com/ Unconscious Repressed Memory Is Scientifically Questionable Lawrence Patihis, Scott O. Lilienfeld, Lavina Y. Ho and Elizabeth F. Loftus Psychological Science 2014 25: 1967 originally published online 18 August 2014 DOI: 10.1177/0956797614547365 The online version of this article can be found at: http://pss.sagepub.com/content/25/10/1967 Published by: http://www.sagepublications.com On behalf of: Association for Psychological Science Additional services and information for Psychological Science can be found at: Email Alerts: http://pss.sagepub.com/cgi/alerts Subscriptions: http://pss.sagepub.com/subscriptions Reprints: http://www.sagepub.com/journalsReprints.nav Permissions: http://www.sagepub.com/journalsPermissions.nav >> Version of Record - Oct 8, 2014 OnlineFirst Version of Record - Aug 18, 2014 What is This? Downloaded from pss.sagepub.com at UNIV CALIFORNIA IRVINE on October 29, 2014
Designer peptide surfactants stabilize diverse functional membrane proteins

Multi-spanning integral membrane proteins, including G-protein coupled receptors (GPCR), ion channels, and ion transporters, comprise a major class of drug targets. However, despite their vital importance, most molecular structures of membrane proteins remain elusive. This is largely due to lack of effective materials and methods to stabilize their functional conformation for sufficient time. Thus finding optimal surfactants and developing new approaches to study fundamental properties of unstable membrane proteins is urgently needed. In this tutorial review we summarize designer peptides with surfactant properties and their usefulness to stabilize membrane proteins. These peptide surfactants present new opportunities for the stabilization and characterization of diverse membrane proteins. Previous studies on the interaction between surfactant peptides and membrane proteins revealed strategies to design new peptides tailor-made for the stabilization of specific proteins. We review examples of solubilization, purification, long-term stabilization of membrane proteins, and the design principles of peptide sequences. We discuss future trends for exploiting spatial features, thermodynamic parameters, and self-assembling properties to create peptide surfactant structures to facilitate the characterization of diverse membrane proteins.
Choice, circumstance, and the value of equality

Many recent political philosophers have attempted to demonstrate that choice and responsibility can be incorporated into the framework of an egalitarian theory of distributive justice. This article argues, however, that the project of developing a responsibility-based conception of egalitarian justice is misconceived. The project represents an attempt to defuse conservative criticism of the welfare state and of egalitarian liberalism more generally. But by mimicking the conservative’s emphasis on choice and responsibility, advocates of responsibility-based egalitarianism unwittingly inherit the conservative’s unsustainable justificatory ambitions, unattractive moralism, and questionable metaphysical commitments. More importantly, they misrepresent the nature of our concern with equality as a value.
Real-time secondary markets for spectrum

Abstract Spectrum licensing enables quality of service guarantees, but often leads to inefficient use of spectrum. Unlicensed spectrum promotes efficiency through sharing, but quality of service cannot be guaranteed, which is a serious problem for some applications. Such applications may be better served by a real-time secondary market, where secondary users ask the license-holder for temporary access to spectrum as needed. Access is granted when and only when quality of service requirements can be met for both license-holder and secondary users. This paper quantitatively assesses real-time secondary markets for the special case of a cellular license-holder. It demonstrates that many secondary users can access spectrum with little impact on the primary cellular customers, and that cellular carriers profit even if the price for secondary access is quite low. Finally, it addresses the challenges of transferring funds from secondary user to license-holder.
The Pattern and Distribution of Deleterious Mutations in Maize

Most nonsynonymous mutations are thought to be deleterious because of their effect on protein sequence and are expected to be removed or kept at low frequency by the action of natural selection. Nonetheless, the effect of positive selection on linked sites or drift in small or inbred populations may also impact the evolution of deleterious alleles. Despite their potential to affect complex trait phenotypes, deleterious alleles are difficult to study precisely because they are often at low frequency. Here, we made use of genome-wide genotyping data to characterize deleterious variants in a large panel of maize inbred lines. We show that, despite small effective population sizes and inbreeding, most putatively deleterious SNPs are indeed at low frequencies within individual genetic groups. We find that genes associated with a number of complex traits are enriched for deleterious variants. Together, these data are consistent with the dominance model of heterosis, in which complementation of numerous low-frequency, weak deleterious variants contribute to hybrid vigor.
FocusCheck: a tool for model checking and debugging sequential c programs

We present the FocusCheck model-checking tool for the verification and easy debugging of assertion violations in sequential C programs. The main functionalities of the tool are the ability to: (a) identify all minimum-recursion, loop-free counter-examples in a C program using on-the-fly abstraction techniques; (b) extract focus-statement sequences (FSSs) from counter-examples, where a focus statement is one whose execution directly or indirectly causes the violation underlying a counter-example; (c) detect and discard infeasible counter-examples via feasibility analysis of the corresponding FSSs; and (d) isolate program segments that are most likely to harbor the erroneous statements causing the counter-examples. FocusCheck is equipped with a smart graphical user interface that provides various views of counter-examples in terms of their FSSs, thereby enhancing usability and readability of model-checking results.
Prevalence of Undiagnosed Pernicious Anemia in the Elderly

Background: Existing information about the prevalence of pernicious anemia is largely based on older surveys that favored florid manifestations, tended to be retrospective analyses of previously diagnosed disease, and usually studied homogeneous European populations. The lack of current data in the United States has, among other things, hampered discussions of the proposal to increase folate intake by the general population. Objective: To estimate the prevalence of undiagnosed and untreated pernicious anemia among the elderly. Methods: A prospective survey of cobalamin levels and anti—intrinsic factor antibody was done in the elderly. Blood testing was done in 729 people aged 60 years or older and follow-up assessment with the Schilling test and other tests was offered when results were abnormal. Results: Seventeen subjects were found to have pernicious anemia, usually with only minimal clinical manifestations of cobalamin deficiency. Although cobalamin deficiency had been suspected by the physicians of three subjects, they had been treated inadequately and still had evidence of deficiency. Excluding these three partially treated subjects from the analysis, 1.9% of the survey population had unrecognized and untreated pernicious anemia. The prevalence was 2.7% in women and 1.4% in men; 4.3% of the black women and 4.0% of the white women had pernicious anemia. Conclusions: Undiagnosed pernicious anemia is a common finding in the elderly, especially among black and white women. If these findings can be extrapolated, almost 800000 elderly people in the United States have undiagnosed and untreated pernicious anemia, and, thus, would be at possible risk for masked cobalamin deficiency if exposed to large amounts of folate. This number does not include those elderly with cobalamin deficiency caused by other disorders or the still unknown number of younger people with unrecognized pernicious anemia and other causes of deficiency. ( Arch Intern Med. 1996;156:1097-1100 )
Conflict Probability Estimation for Free Flight

The safety and efficiency of free flight will benefit from automated conflict prediction and resolution advisories. Conflict prediction is based on trajectory prediction and is less certain the farther in advance the prediction, however. An estimate is therefore needed of the probability that a conflict will occur, given a pair of predicted trajectories and their levels of uncertainty. This paper presents a method to estimate that conflict probability. The trajectory prediction errors are modeled as normally distributed, and the two error covariances for an aircraft pair are combined into a single, equivalent covariance of the relative position. A coordinate transformation is then used to derive an analytical solution. Numerical examples and a Monte Carlo validation are presented. (Author)
Performance of Joint Spectrum Sensing and MAC Algorithms for Multichannel Opportunistic Spectrum Access Ad Hoc Networks

We present an analytical framework to assess the link layer throughput of multichannel Opportunistic Spectrum Access (OSA) ad hoc networks. Specifically, we focus on analyzing various combinations of collaborative spectrum sensing and Medium Access Control (MAC) protocol abstractions. We decompose collaborative spectrum sensing into layers, parametrize each layer, classify existing solutions, and propose a new protocol called Truncated Time Division Multiple Access (TTDMA) that supports efficient distribution of sensing results in “K out of N” fusion rule. In case of multichannel MAC protocols, we evaluate two main approaches of control channel design with 1) dedicated and 2) hopping channel. We propose to augment these protocols with options of handling secondary user (SU) connections preempted by primary user (PU) by 1) connection buffering until PU departure and 2) connection switching to a vacant PU channel. By comparing and optimizing different design combinations, we show that 1) it is generally better to buffer preempted SU connections than to switch them to PU vacant channels and 2) TTDMA is a promising design option for collaborative spectrum sensing process when K does not change over time.
Financial Reporting System Choice and Disclosure Management

We examine the efficiency implications of a manager's financial reporting system choice and disclosure management. When a manager has some private information that is not captured by a firm's financial reporting system and may manipulate the financial report at some cost, we show that the manager may not choose the most precise financial reporting system. We examine how reporting system choice varies with the precision of the manager's private information captured by the reporting system, precision of information that is not captured by the reporting system, and the manager's cost of manipulating the report. We consider the effect of reporting discretion on the efficiency with which investors allocate resources.
Rapid Perturbation of Free‐Energy Landscapes: From In Vitro to In Vivo

Biological systems are often studied under the most "physiological" conditions possible. However, purposeful perturbation of biological systems can provide much information about their dynamics, robustness, and function. Such perturbations are particularly easy to apply at the interface of molecular biophysics and cellular biology, at which complex and highly regulated networks emerge from the behavior of individual biomolecules. Due to the size of diffusion coefficients and the length scale of biomolecules, the fastest timescales at this interface extend to below a microsecond. Thus perturbations must be induced and detected rapidly. We focus on examples of proteins and RNAs interacting with themselves (folding) or one another (binding, signaling). Beginning with general principles that have been learned from simple models and perturbation experiments in vitro, we progress to more complex environments that mimic aspects of the living cell, and finally rapid perturbation experiments in living cells. On the experimental side we highlight in particular two classes of rapid perturbation methods (nanoseconds to seconds) that have been traditionally employed in biophysical chemistry, but that will become increasingly important in cell biology and in vivo: fast relaxation techniques and phase-sensitive modulation techniques. These techniques are now increasingly married with imaging to produce a spatiotemporal map of biomolecular stability, dynamics and, in the near future, interaction networks inside cells. Many important chemical processes occur on biologically fast timescales, and yet have important ramifications for slower biological networks.
Natural Product Synthesis at the Interface of Chemistry and Biology

Nature has evolved to produce unique and diverse natural products that possess high target affinity and specificity. Natural products have been the richest sources for novel modulators of biomolecular function. Since the chemical synthesis of urea by Wohler, organic chemists have been intrigued by natural products, leading to the evolution of the field of natural product synthesis over the past two centuries. Natural product synthesis has enabled natural products to play an essential role in drug discovery and chemical biology. With the introduction of novel, innovative concepts and strategies for synthetic efficiency, natural product synthesis in the 21st century is well poised to address the challenges and complexities faced by natural product chemistry and will remain essential to progress in biomedical sciences.
Coupled-mode theory for stimulated Raman scattering in high-Q/Vm silicon photonic band gap defect cavity lasers

We examine the dynamics of stimulated Raman scattering in designed high-Q/Vm silicon photonic band gap nanocavities through the coupled-mode theory framework towards optically-pumped silicon lasing. The interplay of other χ(3) effects such as two-photon absorption and optical Kerr, related free-carrier dynamics, thermal effects, as well as linear losses such as cavity radiation and linear material absorption are included and investigated numerically. Our results clarify the relative contributions and evolution of the mechanisms, and demonstrate the lasing and shutdown thresholds. Our studies illustrate the conditions for continuous-wave and pulsed highly-efficient Raman frequency conversion for practical realization in monolithic silicon high-Q/Vm photonic band gap defect cavities.
Gravitational Microlensing near Caustics. I. Folds

We study the local behavior of gravitational lensing near fold catastrophes. Using a generic form for the lensing map near a fold, we determine the observable properties of the lensed images, focusing on the case in which the individual images are unresolved, i.e., microlensing. Allowing for images not associated with the fold, we derive analytic expressions for the photometric and astrometric behavior near a generic fold caustic. We show how this form reduces to the more familiar linear caustic, which lenses a nearby source into two images that have equal magnification, opposite parity, and are equidistant from the critical curve. In this case, the simplicity and high degree of symmetry allow for the derivation of semianalytic expressions for the photometric and astrometric deviations in the presence of finite sources with arbitrary surface brightness profiles. We use our results to derive some basic properties of astrometric microlensing near folds; in particular, we predict, for finite sources with uniform and limb-darkening profiles, the detailed shape of the astrometric curve as the source crosses a fold. We find that the astrometric effects of limb darkening will be difficult to detect with the currently planned accuracy of the Space Interferometry Mission for Galactic bulge sources; however, this also implies that astrometric measurements of other parameters, such as the size of the source, should not be compromised by an unknown amount of limb darkening. We verify our results by numerically calculating the expected astrometric shift for the photometrically well-covered Galactic binary lensing event OGLE-1999-BUL-23, finding excellent agreement with our analytic expressions. Our results can be applied to any lensing system with fold caustics, including Galactic binary lenses and quasar microlensing.
Generic Product Strategies for Emerging Market Exports into Triad Nation Markets: A Mimetic Isomorphism Approach

ABSTRACT Based on the concept of mimetic isomorphism, we theorize that, by imitating the home country MNE modal generic product strategy in each Triad nation, emerging market firms (EMFs) can improve their export performance satisfaction. We hypothesize that EMFs which: (1) target the EU and use a Premium strategy, (2) target Japan and use a Superior Value strategy, or (3) target the USA and use an Economy strategy will, on average, achieve higher levels of satisfaction with export performance than EMFs that enter emerging markets or EMFs that employ other product strategies in Triad nation markets. Our hypothesis is tested and supported on a sample of Romanian and Chinese exporters. Managerial implications of our theory and findings are discussed.