cssi/SciSciGPT-SciSciNet huggingface dataset:
Anderson Localization, Non-linearity and Stable Genetic Diversity

In many models of genotypic evolution, the vector of genotype populations satisfies a system of linear ordinary differential equations. This system of equations models a competition between differential replication rates (fitness) and mutation. Mutation operates as a generalized diffusion process on genotype space. In the large time asymptotics, the replication term tends to produce a single dominant quasi-species, unless the mutation rate is too high, in which case the asymptotic population becomes de-localized. We introduce a more macroscopic picture of genotypic evolution wherein a random fitness term in the linear model produces features analogous to Anderson localization. When coupled with density dependent non-linearities, which limit the population of any given genotype, we obtain a model whose large time asymptotics display stable genotypic diversity.
Aggregate Income Shocks and Infant Mortality in the Developing World

Health and income are strongly correlated both within and across countries, yet the extent to which improvements in income have a causal effect on health status remains controversial. The authors investigate whether short-term fluctuations in aggregate income affect infant mortality using an unusually large data set of 1.7 million births in 59 developing countries. The authors show a large, negative association between per capita GDP and infant mortality. Female infant mortality is more sensitive than male infant mortality to negative economic shocks, suggesting that policies that protect the health status of female infants may be especially important during economic downturns.
Building a Model for Online Distance Courses Through Social Media and Networks

This article describes the affordances of social media and networks for online Elementary German courses that have been taught at the University of Pennsylvania since 2010. These online courses were created to provide students the opportunity to take Elementary German as part of the language requirement for Penn credit during the summer months when students are away from campus. Like their face-to-face counterparts, the online courses are grounded on the principles of communicative language teaching and learning but clearly reveal the potential of these principles to maximize participation, promote learner autonomy and influence student outcomes when applied to collaborative online learning spaces. This paper explains the pedagogy behind the online courses, outlines their relationship to the face-to-face language classroom, and describes how student interactions are key to the learning process. It considers the importance of electronic and digital literacy Warschauer, 2006 to the growth of new methodologies, materials development, assessment, articulation, intercultural competence, and student progress. This paper also compares the instructor's experiences of teaching in the online environment with those of the face-to-face classroom and discusses how these distinct and separate learning spaces are in many ways related and can inform each other. Finally, the author considers new possibilities for language learning through emerging technologies.
Triboelectric, corona, and induction charging of insulators as a function of pressure

Theoretical and experimental research that was carried out showed that the surface charge on an insulator after triboelectric charging with another insulator is rapidly dissipated with lowered atmospheric pressure. This pressure discharge is consistent with surface ions being evaporated off the surface once their vapor pressure is attained. In this paper, we will report on the results of three different charging techniques (triboelectric, corona, and induction) carried out on selected polymers with varying atmospheric pressure. This data will show that ion exchange between the insulators is the mechanism responsible for most of the surface charge on the polymers.
Reversals of task duration estimates: Thinking how rather than why shrinks duration estimates for simple tasks, but elongates estimates for complex tasks

Abstract Individuals often estimate the duration of tasks that others are engaged in (time a colleague would take to write a report, time a spouse would take to get dressed for a party, etc.). Construal-level theory suggests that thinking about ‘how’ (vs. ‘why’) a task is to be completed shrinks duration estimates. We argue that this effect arises for simple tasks, but complex tasks yield a reversal. Specifically, because ‘how’ participants are more attuned to the greater number of steps required for complex tasks, thinking ‘how’ (vs. ‘why’) elongates estimates. In four experiments, we test this theory using different scenarios, manipulated and measured complexity, and subjective and objective time estimates. Support emerges for the reversal, and for mediation via the perceived number of steps. Implications arise for four research domains: (a) construal level, (b) estimates of task duration, (c) planning fallacy, and (d) task complexity.
Prospects for advanced rocket-powered launch vehicles

The potential for advanced rocket-powered launch vehicles to meet the challenging cost, operational, and performance demands of space transportation in the early 21st century is examined. Space transportation requirements from recent studies underscoring the need for growth in capacity in support of an increasing diversity of space activities and the need for significant reductions in operational and life-cycle costs are reviewed. Fully reusable rocket powered concepts based on moderate levels of evolutionary advanced technology are described. These vehicles provide a broad range of attractive concept alternatives with the potential to meet demanding operational and cost goals and the flexibility to satisfy a variety of vehicle architecture, mission, vehicle concept, and technology options.
Control of the fields due to superconductor magnetization in the SSC magnets

Field uniformity of better than one part in 10,000 is required for the dipole magnets for the Superconducting Super Collider (SSC). The high field dipole and quadrupole magnets proposed for the SSC generate higher multipole components of field due to magnetization (persistent currents) in the superconductor. When the superconductor filament diameter is of the order of 20μm, the sextupole term alone is about 17 parts in 10,000 at an injection induction of 0.3 tesla in the SSC dipole magnets at a radius of 1 cm. This paper shows calculations of the magnetization phenomena which agree very well with magnetic measurement. Several passive methods for removing the sextupole component and higher components of the field generated by magnetization of the superconductor in the SSC dipole magnets are presented in the paper.
Synthesis and structure of the [(UO2)S4]6- anion: a cation-stabilized uranyl sulfide.

The new uranyl sulfide anion [(UO2)S4]6– has been synthesized and characterized as a cation-stabilized anion in the compound Na2Ba2(UO2)S4. This compound was synthesized at 873 K from the solid-state reaction of uranium, Na2O2, BaS, and sulfur. The coordination about the U6+ center in [(UO2)S4]6– is square bipyramidal with the uranyl O atoms 180° apart and four equatorial S atoms. The Na+ and Ba2+ cations form interactions with the uranyl O atoms. Despite the inherent difficulties involved in the synthesis of complex uranium oxysulfides, it is demonstrated that under the right reaction conditions the UO22+ species can be produced in situ and result in totally new chalcogen derivatives.
Crony Capitalism and Financial System Stability

Prior to the Asian financial crisis, the cozy relationships between corporations, governments, and banks were seen as a potent force for economic growth and development. In this article we examine the institution of crony capitalism. Under conditions in which the Second Welfare Theorem does not hold, there is a role for government. Some governmental institutions do encourage more risky, high-payoff entrepreneurial activities. Our aim is to examine crony capitalism as a potential source of government activity that enhances economic productivity. In addition, we explore the conditions under which the government activity can instigate a financial crisis.
A novel pyrrole synthesis via reaction of ketones with N-aminoimides

Abstract A new, mild synthesis of pyrroles using N-aminoimides and a ketone is described. The reaction has been utilized in the synthesis of dimeric morphinans containing a connecting pyrrole ring. The reaction appears to proceed through a diacylhydrazone intermediate, and it is suggested that the driving force behind the reaction is the facility with which a protonated imide moiety operates as a leaving group.
GASP: Geometric Association with Surface Patches

A fundamental challenge to sensory processing tasks in perception and robotics is the problem of obtaining data associations across views. We present a robust solution for ascertaining potentially dense surface patch (super pixel) associations, requiring just range information. Our approach involves decomposition of a view into regularized surface patches. We represent them as sequences expressing geometry invariantly over their super pixel neighborhoods. Uniquely consistent partial orderings are utilized for the same. We match these representations robustly through an optimal sequence comparison metric based on the Damerau-Levenshtein distance. The approach is able to perform under wide baselines, heavy rotations, significant occlusions and partially overlapping content. The technique does not require any priors -- motion or otherwise, and does not make restrictive assumptions on scene structure and sensor movement. It does not require appearance -- is hence more widely applicable than appearance reliant methods, and invulnerable to related ambiguities such as texture less or aliased content. We present promising qualitative and quantitative results under diverse settings, along with comparatives with popular approaches based on range as well as RGB-D data.
Proper forcing and rectangular ramsey theorems

I prove forcing preservation theorems for products of definable partial orders preserving cofinality of the meager or null ideal. Rectangular Ramsey theorems for the related ideals follow from the proofs.
SDSS J1650+4251: A New Gravitational Lens*

We report that the Sloan Digital Sky Survey quasar SDSS J165043.44+425149.3 is gravitationally lensed into two images, based on observations obtained with the WIYN 3.5 m telescope at the Kitt Peak National Observatory. The lensed quasar, at a redshift of z = 1.547, appears as two images separated by 12 with B-band magnitudes of 17.8 and 20.0. The lensing galaxy is clearly detected in I-band images obtained in 03 seeing after point-spread function subtraction of the two quasar images. A strong metal-line absorption system is also identified in the unresolved SDSS spectrum of the double quasar, suggesting a plausible lens redshift of z = 0.58. The UBRI flux ratios of the pair vary significantly, from 8.5 : 1 in the blue to 5.4 : 1 in the red, a difference of 0.5 mag, and are likely due to differential reddening through the lensing galaxy, microlensing in one or both quasar images, or some combination of the two. Optical monitoring of the quasar pair, particularly at blue wavelengths, will be needed to determine if microlensing is indeed significant. The predicted differential time delay between the quasar images is on the order of 1 month, assuming the intervening absorption system is due to the lensing galaxy.
Mechanisms and geochemical significance of Si–Al substitution in zeolite solid solutions

Abstract Rock-forming zeolites often exhibit complex solid solutions reflecting isomorphous substitutions between Si and Al in tetrahedral framework sites, between charge-balancing extraframework cations, and between water molecules and vacancies. Although the number of moles of charge on extraframework cations in a zeolite must equal the moles of Al in order to maintain charge balance, the relationships between Si–Al and extraframework substitutions vary considerably across this mineral group. Review of available compositional data suggests that there are three main modes of Si–Al substitution in zeolites: 1) coupled CaAl–NaSi substitution; 2) coupled substitution of a single extraframework cation plus Al for Si; and 3) completely uncoupled substitution among extraframework cations and Si and Al on tetrahedral sites. Among zeolites that exhibit the latter two modes of solid solution, Si–Al substitution can be described by an SiO 2 (± H 2 O) compositional exchange vector from a hypothetical, pure-silica endmember composition. Recent calorimetric, structural, and theoretical investigations suggest that Si–Al substitution follows a non-ideal, athermal solution model characterized by no excess enthalpies of mixing and negative excess entropies of mixing. Because Si–Al exchange in these minerals can be explicitly or implicitly described by exchange of an SiO 2 component, the Si/Al ratio in their framework can be predicted solely as a function of temperature, pressure, and the chemical potential of SiO 2 . Application of this model leads to calculated Si/Al ratios in stilbite (coexisting with albite), analcime, and chabazite consistent with observed mineral compositions and parageneses in very low-grade metamorphic environments. Coexistence of silica polymorphs with zeolites containing SiO 2 · n H 2 O exchange vectors potentially provides a means of performing thermobarometric calculations in very low-grade metamorphic and diagenetic environments.
Global Cities Are Coastal Cities Too: Paradox in Sustainability?

World-wide, most global cities are located in coastal zones, but a paradox of sustainability is especially striking for US global cities. This article examines such a paradox, drawn between globali...
Protoearth mass shedding and the origin of the moon

Darwin's (1980) theory of lunar formation from the earth by means of a rotationally driven dynamic fission instability is presently considered in view of viscous shear's maintenance of solid body rotation throughout the protoearth's accretion phase. Assuming the appropriateness of a polytropic account of the protoearth, it is unlikely that dynamic fission could have occurred; instantaneous spin-up following a giant impact would instead have led to mass shedding. The dynamical phenomenon of mass shedding is here explored on the basis of numerical models for a self-gravitating, axisymmetric, polytropic and dissipative protoearth. It is concluded that mass shedding from the protoearth mantle after a giant impact and explosion could have contributed substantial matter to a lunar disk.
Extrahelical Damaged Base Recognition by DNA Glycosylase Enzymes

The efficient enzymatic detection of damaged bases concealed in the DNA double helix is an essential step during DNA repair in all cells. Emergent structural and mechanistic approaches have provided glimpses into this enigmatic molecular recognition event in several systems. A ubiquitous feature of these essential reactions is the binding of the damaged base in an extrahelical binding mode. The reaction pathway by which this remarkable extrahelical state is achieved is of great interest and even more debate.
Experimental measurement of the dispersion relations of gold nanoparticle chains

The dispersion relations of plasmon modes of gold nanoparticle chains are measured, and compared with quasistatic theory. In addition to one longitudinal and one transverse mode, the results reveal a third mode, not previously observed.
Detectability of a subdominant density component of cold dark matter

Abstract Here we examine the detectability of collisionless dark matter candidates that may constitute not all but only a subdominant component of galactic cold dark matter. We show that direct WIMP searches would not be severely affected by the reduced density. In fact, the direct detection rates of neutralinos stay almost constant even if neutralinos constitute 1% of the halo dark matter. Only for lower densities do the rates decrease with density. Even neutralinos accounting for only 10 −4 of the local dark halo density are within proposed future discovery limits. We comment also on axions and indirect WIMP searches.
The Role of Retiree Health Insurance in the Early Retirement of Public Sector Employees

Most government employees have access to retiree health coverage, which provides them with group health coverage even if they retire before Medicare eligibility. We study the impact of retiree health coverage on the labor supply of public sector workers between the ages of 55 and 64. We find that retiree health coverage raises the probability of stopping full time work by 4.3 percentage points (around 38 percent) over two years among public sector workers aged 55-59, and by 6.7 percentage points (around 26 percent) over two years among public sector workers aged 60-64. In the younger age group, retiree health insurance mostly seems to facilitate transitions to part-time work rather than full retirement. However, in the older age group, it increases the probability of stopping work entirely by 4.3 percentage points (around 22 percent).
(+/-)-4-[(N-allyl-cis-3-methyl-4-piperidinyl)phenylamino]-N,N-diethylbenzamide displays selective binding for the delta opioid receptor.

Abstract Racemic 4-[(N-allyl-cis-3-methyl-4-piperidinyl)phenylamino]-N,N-diethylbenzamide (3a) was synthesized and found to have good affinity and selectivity for the δ receptor. these compounds can be viewed as an analog of BW373U86 and SNC-80 where an internal piperazine nitrogen has been transposed with a benzylic carbon. Functionally, 3a behaves as an agonist at the δ receptor with no measurable stimulation of either the μ or k receptor subtypes and was found to be devoid of any measurable amount of antagonist activity for any opioid receptor. A comparison of 3a to SNC-80 and DPDPE in the [35S]GTPγS functional assay suggests that 3a may be more like the peptide DPDPE.
Commuting Polynomials and Polynomials with same Julia Set

It has been known since Julia that polynomials commuting under composition have the same Julia set. More recently in the works of Baker and Eremenko, Fernandez, and Beardon, results were given on the converse question: When do two polynomials have the same Julia set? We give a complete answer to this question and show the exact relation between the two problems of polynomials with the same Julia set and commuting pairs.
Dynamics Modeling and Analysis of a Swimming Microrobot for Controlled Drug Delivery

Dynamics modeling and analysis of a tiny swimming robot, which is composed of a helix type head and an elastic tail, is presented in this paper. The microrobot is designed for controlled drug delivery. It is at the micrometer scale and suitable for a swimming environment under low Reynolds number (Re). The head of the swimming robot is driven by an external rotating magnetic field, which enables it to be operated wirelessly. The spiral-type head accommodates communication and control units and serves as the base for the elastic tail. When a rotating magnetic field is applied, the head rotates synchronously with the field, generating and propagating driving torque to the straight elastic tail. When the driving torque reaches a threshold, dramatic deformation takes place on the elastic tail. The tail then transforms into a helix and generates propulsive thrust. The entire tail also serves as a drug reservoir. This paper focuses on analyzing the dynamics of the microrobot using resistive force theory (RFT), and comparing the propulsion performance with other rigid-body microrobots.
Pulsar and diffuse contributions to the observed galactic gamma radiation

With the acquisition of satellite data on the energy spectrum of galactic gamma-radiation, it is clear that such radiation has a multicomponent nature. A calculation of the pulsar gamma ray emission spectrum is used together with a statistical analysis of recent data on 328 known pulsars to make a new determination of the pulsar contribution to galactic gamma ray emission. The contributions from diffuse interstellar cosmic ray induced production mechanisms to the total emission are then reexamined. It is concluded that pulsars may account for a significant fraction of galactic gamma ray emission.
Heat Transfer Enhancement by Flow Destabilization in Electronic Chip Configurations

Numerical simulations of the flow pattern and forced convective heat transfer in geometries such as those encountered in cooling systems for electronic devices are presented. For Reynolds numbers above the critical one, these flows exhibit a traveling-wave structure with laminar self-sustained oscillations at the least-stable Tollman-Schlichting mode frequency. Three techniques of heat transfer enhancement by flow destabilization in grooved channels are compared on an equal pumping power basis: active flow modulation, passive flow modulation, and supercritical flow destabilization. It is found that the best enhancement system regarding minimum power dissipation corresponds to passive flow modulation in the range of low Nusselt numbers. However, supercritical flow destabilization becomes competitive as the requirement for higher Nusselt numbers begins to dominate the design choices. The hydrodynamic heat transfer numerical results are obtained by direct simulation of the unaveraged energy and Navier-Stokes equations using a spectral-element-Fourier method for the spatial discretization. It is shown that computational heat transfer and, in particular, direct numerical simulation using advanced numerical schemes can contribute significantly in exploring the physics associated with heat transfer enhancement by flow destabilization. >
Antibody catalysis of bimolecular amide formation

Etude de la catalyse de la reaction de formation des carboxamides, par des anticorps monoclonaux anti-phosphonamidates. Selectivite vis-a-vis des amines aromatiques et aliphatiques dans la competition entre la benzylamine et la butylamine dans la formation du carboxamide
Spectral sum rules and Selberg's integral formula

Abstract Using Selberg's integral formula we derive all Leutwyler-Smilga type sum rules for one and two flavors, and for each of the three chiral random matrix ensembles. In agreement with arguments from effective field theory, all sum rules for N f =1 coincide for the three ensembles. The connection between spectral correlations and the low-energy effective partition function is discussed.
Cold forging method for polymer microfabrication

A polymer micro cold forging process was investigated. This method, derived from polymer solid-phase forming, resembles more the metal-forging method than the standard thermoplastic molding protocol. A micro-forging die set was designed and fabricated and a series of cold forging experiments were carried out with varied process conditions, including forging speed, forging pressure, and dwell time. High-aspect-ratio microchannels were fabricated on polytetrafluoroethylene (PTFE) substrates. The dimension of replicated channels was found to be consistent from shot to shot. Owing to instantaneous elastic recovery, the channel has a width about 30% smaller than that on the die. The final channel size is contingent upon the forging process conditions, as well as upon the post-recovery process. Upsetting experiments of PTFE cylindrical samples were carried out to study the fundamental issues on dimensional recovery so as to predict and consequently control the dimensional changes in polymer cold forging. Polym. Eng. Sci. 44:1998–2004, 2004. © 2004 Society of Plastics Engineers.
Method to Quantify Flow Reduction in Aneurysmal Cavities of Lateral Wall Aneurysms Produced by Stent Implants Used for Flow Diversion

SUMMARY Stent implants placed across the neck of cerebral aneurysms are capable of reducing aneurysmal flow when coils are not used for filling the aneurysms. It is important to evaluate the effects of flow reduction caused by stent implants used for the treatment of cerebral aneurysms. Subtracted vortex centers path line method (SVC method) is one of the image post processing methods employed for quantitative flow measurement. We developed a modified SVC method by employing Cinematic Angiography (25 frames/s) and digital video recording (30 frames/s) with a commercial digital camera.We successfully compared the flow effectiveness using a tubular silicon model with a sidewall aneurysm. The result suggests that our modified SVC method is useful for a comparative examination of the effect of aneurysmal flow reduction caused by stent implants.
Identification and Estimation of Online Price Competition With an Unknown Number of Firms

This paper considers identification and estimation of a general model for online price competition. We show that when the number of competing firms is unknown the underlying parameters of the model can still be identified and estimated employing recently developed results on measurement errors. We illustrate our methodology using UK data for personal digital assistants and employ the estimates to simulate competitive effects. Our results reveal that heightened competition has differential effects on the prices paid by different consumer segments.
A NEW ROUTE FOR THE SELECTIVE SYNTHESIS OF 6,6-METHANOFULLERENES. ELECTROSYNTHESIS OF C61HCME3 AND C61HCN

A new fast and simple route for the selective synthesis of methanofullerenes that uses the reaction between the C60 dianion and diodo- or dibromo-reagents is described.
STRONG S-EQUIVALENCE OF ORDERED LINKS

In 2003, Naik and Stanford proved that two S-equivalent knots are related by a finite sequence of doubled-delta moves on their knot diagrams. We show that classical S-equivalence is not sufficient to extend their result to ordered links. We define a new algebraic relation on Seifert matrices, called strong S-equivalence, and prove that two oriented, ordered links L and L′ are related by a sequence of doubled-delta moves if and only if they are strongly S-equivalent. We also show that this is equivalent to the fact that L′ can be obtained from L through a sequence of Y-clasper surgeries, where each clasper leaf has total linking number zero with L.
The Razor's Edge: Distortions and Incremental Reform in the People's Republic of China

In a partially reformed economy, distortions beget distortions. Segments of the economy that are freed from centralized control respond to the rent-seeking opportunities implicit in the remaining distortions of the economy. The battle to capture, and then protect, these rents leads to the creation of new distortions, even as the reform process tries to move forward. In this paper I illustrate this idea with a study of the People's Republic of China. Under the plan, prices were skewed so as to concentrate profits, and hence revenue, in industry. As control over factor allocations was loosened, local governments throughout the economy sought to capture these rents by developing high margin industries. Continued reform, and growing interregional competition between duplicative industries, threatened the profitability of these industrial structures, leading local governments to impose a variety of interregional barriers to trade. Thus, the reform process led to the fragmentation of the domestic market and the distortion of regional production away from patterns of comparative advantage.
A Quantum Mechanical Model of Spherical Supermembranes

We present a quantum mechanical model of spherical supermembranes. Using superfields to represent the cartesian coordinates of the membrane, we are able to exactly determine its supersymmetric vacua. We find there are two classical vacua, one corresponding to an extended membrane and one corresponding to a point-like membrane. For the = 2 case, instanton effects then lift these vacua to massive states. For the = 4 case, there is no instanton tunneling, and the vacua remain massless. Similarities to spherical supermembranes as giant gravitons and in Matrix theory on pp-waves is discussed.
Real-time implementation of a color sorting system

Wood edge glued panels are used extensively in the furniture and cabinetry industries. They are used to make doors, tops, and sides of solid wood furniture and cabinets. Since lightly stained furniture and cabinets are gaining in popularity, there is an increasing demand to color sort the parts used to make these edge glued panels. The goal of the sorting processing is to create panels that are uniform in both color and intensity across their visible surface. If performed manually, the color sorting of edge-glued panel parts is very labor intensive and prone to error. This paper describes a complete machine vision system for performing this sort. This system uses two color line scan cameras for image input and a specially designed custom computing machine to allow real-time implementation. Users define the number of color classes that are to be used. An 'out' class is provided to handle unusually colored parts. The system removes areas of character mark, e.g., knots, mineral streak, etc., from consideration when assigning a color class to a part. The system also includes a better face algorithm for determining which part face would be the better to put on the side of the panel that will show. The throughput is two linear feet per second. Only a four inch between part spacing is required. This system has undergone extensive in plant testing and will be commercially available in the very near future. The results of this testing will be presented.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Optimal Pellet Geometries for Thermoelectric Power Generation

The geometry of the semiconductor pellets (i.e., the number of them and their height) within thermoelectric modules (TEMs) operating in generation mode is optimized in order to maximize either their performance (i.e., output power) or their conversion efficiency for a specified performance. This is accomplished for a specified resistive load on a TEM as a function of its effective footprint, i.e., sum of the cross-sectional areas of its pellets. The load resistances which maximize performance or efficiency when pellet geometry is specified are also provided. The analyses are performed in the absence and then presence of electrical contact resistance at the interconnects between pellets. They apply for a prescribed temperature difference across a TEM that is small enough for the properties of its pellets to be considered constant. Examples illustrate the application and implications of the results.
Probabilistic models for damage and self-repair in DNA self-assembly

To date, research on DNA self-assembly-based nanostructures has mostly been on one-time assembly. However, DNA nanostructures are very fragile and prone to damage. Knowing the extent of damage that can occur under various physical conditions can be useful in designing robust self-assembled nanostructures. This paper presents simple models for estimating the extent of damage in DNA nanostructures due to various external forces, with emphasis on mechanical and thermal forces. We note that these models have not been validated against experimental data. As such, they are only meant to serve as a basis for designing DNA nanostructures that are robust to external damage. We conclude with a discussion on computing the probability of repair of a damaged nanostructure assuming no change in the design of the self-assembling components.
Social Security as a financial asset: gender- specific risks and returns

Social Security is a financial asset whose ‘purchase’ is compulsory for most working individuals. This paper shows that the return on Social Security during the individual’s working lifetime is related to the rate of change of aggregate labor income. If an individual’s labor income is strongly related to aggregate labor income, then the Social Security asset is a particularly unattractive asset. In this situation, the individual would benefit from a reformed Social Security system that would permit investment of retirement funds in other financial assets. This paper investigates how this aspect of Social Security risk varies across groups of individuals who dier according to gender; education; race; and age. The main finding is that there are important dierences across groups in this component of Social Security risk, as captured by the sensitivity of individual-level income growth to changes in the SSWI. This element of risk is most important for women, especially women who are young-to-middle aged and with more education. This analysis suggests that women would have more to gain, compared with men, from a reformed Social Security system.
Efficient moment-based inference of admixture parameters and sources of gene flow

The recent explosion in available genetic data has led to significant advances in understanding the demographic histories of and relationships among human populations. It is still a challenge, however, to infer reliable parameter values for complicated models involving many populations. Here, we present MixMapper, an efficient, interactive method for constructing phylogenetic trees including admixture events using single nucleotide polymorphism (SNP) genotype data. MixMapper implements a novel two-phase approach to admixture inference using moment statistics, first building an unadmixed scaffold tree and then adding admixed populations by solving systems of equations that express allele frequency divergences in terms of mixture parameters. Importantly, all features of the model, including topology, sources of gene flow, branch lengths, and mixture proportions, are optimized automatically from the data and include estimates of statistical uncertainty. MixMapper also uses a new method to express branch lengths in easily interpretable drift units. We apply MixMapper to recently published data for Human Genome Diversity Cell Line Panel individuals genotyped on a SNP array designed especially for use in population genetics studies, obtaining confident results for 30 populations, 20 of them admixed. Notably, we confirm a signal of ancient admixture in European populations-including previously undetected admixture in Sardinians and Basques-involving a proportion of 20-40% ancient northern Eurasian ancestry.
SHIELD: Social sensing and Help In Emergency using mobiLe Devices

School and College campuses face a perceived threat of violent crimes and require a realistic plan against unpredictable emergencies and disasters. Existing emergency systems (e.g., 911, campus-wide alerts) are quite useful, but provide delayed response (often tens of minutes) and do not utilize proximity or locality. There is a need to exploit proximitybased help for immediate response and to deter any crime. In this paper, we propose SHIELD, an on-campus emergency rescue and alert management service. It is a fully distributed infrastructureless platform based on proximity-enabled trust and cooperation. It relies on nearby localized responses sent using Bluetooth and/or WiFi to achieve minimal response time and maximal availability thereby augmenting the traditional notion of centralized emergency services. Analysis of campus crime statistics and WLAN traces surprisingly show a strong positive correlation (over 55%) between on-campus crime statistics and spatiotemporal density distribution of on-campus mobile users. This result is promising to develop a platform based on mutual trust and cooperation. Finally, we also show a prototype application to be used in such scenarios.
CMOS-MEMS Capacitive Humidity Sensor

A high-sensitivity capacitive humidity sensor intended for use as part of a respirator end-of-service-life indicator system is presented. This paper reports a method for improving the sensitivity of integrated capacitive chemical sensors by removing the underlying substrate. The sensor is integrated with CMOS testing electronics using maskless postprocessing followed by ink-jet deposition of a sensitive polymer. Two different methods of depositing polymer, namely, capillary wicking and coating the top surface directly, were investigated. The sensors had measured sensitivities of 0.16% to 0.18% change in capacitance per percent relative humidity, which is the highest demonstrated for an integrated capacitive humidity sensor. Temperature sensitivity of the sensor, which is an important criterion for a sensor intended for a variety of different ambient conditions, was measured to be 0.07%/°C. The cross sensitivities to toluene and acetone, which are two common industrial solvents that are filtered by respirator cartridges, were measured to be 2.4 × 10-4 and 9.0 × 10-5%/ppm, respectively.
Reflectionless evanescent-wave amplification by two dielectric planar waveguides

Utilizing the underlying physics of evanescent-wave amplification by a negative-refractive-index slab, it is shown that evanescent waves with specific spatial frequencies can also be amplified without any reflection simply by two dielectric planar waveguides. The simple configuration allows one to take advantage of the high resolution limit of a high-refractive-index material without contact with the object.
Publish-subscribe for mobile environments

The Publish-Subscribe paradigm has become an important architectural style for designing distributed systems. In the recent years, we are witnessing an increasing demand for supporting publish-subscribe for mobile computing devices, where conditions used for filtering the data can depend on the particular state of the subscriber (quality of the connection, space and time locality, device capabilities). In this paper we present a stateful model for publish-subscribe systems, suitable for mobile environments. In our system, the server maintains a state for each client, which contains variables that describe the properties of the particular client, such as the quality of the connection or the display size. The interest of each client can be expressed in terms of these variables. Based on the client interests, an associated agent is created on the server. The agent filters the data that reach the client based on the current client state. Experimental results show good performance and scalability of our approach.
Perspectives on Corporate Control: Implications for CEO Compensation

This study examines the influence on CEO paypractices of four corporate control perspectives:managerial control, class hegemony, external control,and efficient market. The results indicate the influence of both market and extra-market controls on thedetermination of CEO pay levels and criteria.Implications for the governance of firms and the studyof corporate control are drawn.
Synthesis and reactions of a zirconocene-benzdiyne equivalent

Abstract The zirconocene complex of 3-methoxy-4-[(methyl)zirconocene]banzyne, 1, has been prepared and isolated as its trimethylphosphine adduct. In addition, the reaction of 1 with a variety of unsaturated organic molecules has been investigated. In these reactions, 1 serves as the synthetic equivalent of the bis(zirconocene)3-mathoxybenzdiyne complex.
On the Polymorphism of Enstatite

The polymorphism of enstatite (MgSiO3) is reviewed. Three stable phases occur—clinoenstatite, orthoenstatite, and protoenstatite, being stable at low, intermediate, and elevated temperatures, respectively — and new data concerning their crystallization from synthetic glasses are summarized. The phase transformations between these polymorphs are discussed, particularly their sensitivity to shear stresses. Finally, the possibility of using one or more of these transformations for toughening silicates is considered.
2-Chloro-1,1,1-Triethoxyethane and its Use in a Versatile Synthesis of Substituted, 2-Chloromethyl Heterocycles Including Benzothiazole and Benzoxazole

Abstract An efficient procedure suitable for large scale preparation of 2-chloro-1,1,1-triethoxyethane and its use in a versatile synthesis of 2-chloromethyl derivatives of an assortment of heterocycles are described.
What shapes perceptions of climate change

Climatechange,asaslowandgradualmodificationofaverageclimateconditions,is adifficultphenomenontodetectandtrackaccuratelybasedonpersonalexperience. Insufficient concern and trust also complicate the transfer of scientific descriptions of climate change and climate variability from scientists to the public, politicians, and policy makers, which is not a simple transmission of facts. Instead, worldview and political ideology, two elements of the cultural context of decisions, guide attention toward events that threaten the desired or existing social order, and shape expectations of change, which in turn guide the detection and interpretation of climate events. Action that follows from climate change perceptions can be informed by different processes. Affect-based decisions about climate change are unlikely to motivate significant action, as politicians and the general public are not particularly worried about climate risks, and because attempts to scare people into greater action may have unintended negative consequences. Analysisbased decisions are also unlikely to result in significant action, because of large discounting of uncertain future costs of climate risks compared to the certain and immediate costsof climate change mitigation. Rule-based decisions that determine behavior based on moral or social responsibility may hold out the best prospects for sustainable action.  2010 John Wiley & Sons, Ltd. WIREs Clim Change 2010 1 332‐342
Scaling Relations from Sunyaev-Zel'dovich Effect and Chandra X-ray measurements of high-redshift galaxy clusters

We present Sunyaev-Zel'dovich Effect (SZE) scaling relations for 38 massive galaxy clusters at redshifts 0.14 ≤ z≤ 0.89, observed with both the Chandra X-ray Observatory and the centimeter-wave SZE imaging system at the BIMA and OVRO interferometric arrays. An isothermal β-model with the central 100 kpc excluded from the X-ray data is used to model the intracluster medium and to measure global cluster properties. For each cluster, we measure the X-ray spectroscopic temperature, SZE gas mass, total mass, and integrated Compton y-parameters within r2500. Our measurements are in agreement with the expectations based on a simple self-similar model of cluster formation and evolution. We compare the cluster properties derived from our SZE observations with and without Chandra spatial and spectral information and find them to be in good agreement. We compare our results with cosmological numerical simulations and find that simulations that include radiative cooling, star formation, and feedback match well both the slope and normalization of our SZE scaling relations.
Impacts of fire emissions and transport pathways on the interannual variation of CO in the tropical upper troposphere

Abstract. This study investigates the impacts of fire emission, convection, various climate conditions and transport pathways on the interannual variation of carbon monoxide (CO) in the tropical upper troposphere (UT), by evaluating the field correlation between these fields using multi-satellite observations and principle component analysis, and the transport pathway auto-identification method developed in our previous study. The rotated empirical orthogonal function (REOF) and singular value decomposition (SVD) methods are used to identify the dominant modes of CO interannual variation in the tropical UT and to study the coupled relationship between UT CO and its governing factors. Both REOF and SVD results confirm that Indonesia is the most significant land region that affects the interannual variation of CO in the tropical UT, and El Nino–Southern Oscillation (ENSO) is the dominant climate condition that affects the relationships between surface CO emission, convection and UT CO. In addition, our results also show that the impact of El Nino on the anomalous CO pattern in the tropical UT varies strongly, primarily due to different anomalous emission and convection patterns associated with different El Nino events. In contrast, the anomalous CO pattern in the tropical UT during La Nina period appears to be less variable among different events. Transport pathway analysis suggests that the average CO transported by the "local convection" pathway (ΔCOlocal) accounts for the differences of UT CO between different ENSO phases over the tropical continents during biomass burning season. ΔCOlocal is generally higher over Indonesia–Australia and lower over South America during El Nino years than during La Nina years. The other pathway ("advection within the lower troposphere followed by convective vertical transport") occurs more frequently over the west-central Pacific during El Nino years than during La Nina years, which may account for the UT CO differences over this region between different ENSO phases.
The distribution of values in the quadratic assignment problem

We obtain a number of results regarding the distribution of values of a quadratic function f on the set of n × n permutation matrices (identified with the symmetric group Sn) around its optimum (minimum or maximum). We estimate the fraction of permutations σ such that f(σ) lies within a given neighborhood of the optimal value of f and relate the optimal value with the average value of f over a neighborhood of the optimal permutation. We describe a natural class of functions (which includes, for example, the objective function in the Traveling Salesman Problem) with a relative abundance of near-optimal permutations. Also, we identify a large class of functions f with the property that permutations close to the optimal permutation in the Hamming metric of Sn tend to produce near optimal values of f (such is, for example, the objective function in the symmetric Traveling Salesman Problem). We show that for general f, just the opposite behavior may take place: an average permutation in the vicinity of the optimal permutation may be much worse than an average permutation in the whole group Sn.
Strain recovery and self-healing in dual cross-linked nanoparticle networks

Via computational modeling, we investigate the mechanism of strain recovery in dual cross-linked polymer grafted nanoparticle networks. The individual nanoparticles are composed of a rigid spherical core and a corona of grafted polymers that encompass reactive end groups. With the overlap of the coronas on adjacent particles, the reactive end groups form permanent or labile bonds, and thus form a “dual cross-linked” network. We consider the strain recovery of the material after it is allowed to relax from the application of a tensile force. Notably, the existing labile bonds can break and new bonds can form in the course of deformation. Hence, a damaged material could be “rejuvenated” both in terms of the recovery of strain and the number of bonds, if the relaxation occurs over a sufficiently long time. We show that this rejuvenation depends on the fraction of permanent bonds, strength of labile bonds, and maximal strain. Specifically, we show that while an increase in the labile bond energy leads to formation of a tough material, it also leads to delayed strain recovery. Further, we show that an increase in the fraction of permanent bonds not only enables faster recovery but also yields improved recovery even after multiple stretch–relaxation cycles.
Environmental and brownfield liability: Relative influence on corporate expansion and relocation

Many States in America have enacted laws to encourage redevelopment of contaminated urban properties. The laws attempt to do this by addressing one barrier to redevelopment, the environmental liability attached to contaminated urban properties. In general, the laws attempt to remove or reduce the significance of that barrier by reducing or eliminating the environmental liability risk attached to these properties. Our hypothesis was that these efforts cannot encourage significant redevelopment because they fail to address non‐environmental barriers to urban redevelopment. To determine whether this legislative focus on environmental liability is misplaced, we conducted a survey of Northeast Ohio businesses which had decided, since the enactment of Ohio’s brownfields law, either to move to a new location, or to expand at an existing location. The survey asked businesses to rank the relative importance to their relocation decision of environmental and non‐environmental factors. The results of the survey show ...