cssi/SciSciGPT-SciSciNet huggingface dataset:
Influence of alkyl substituents on the π* negative ion states of benzene and its derivatives: electron transmission spectroscopy of p-alkylanilines

Abstract Electron affinities and electron attachment energies associated with the π* orbitals of several p-alkylanilines (alkyl = Me, Et, i-Pr, and t-Bu) have been determined in the gas phase by electron transmission spectroscopy and have been analyzed by ab initio molecular orbital calculations at the STO-3G and 6-31G levels of basis set. The results lead to the conclusions that (a) the 2A2 negative ion state in toluene lies below the 2B1 state, (b) the 2A2 state is stabilized in toluene relative to benzene by bonding overlap between the ortho carbon (C2(2pπ)) and the Me H(1s) orbitals in the LUMO, (c) the 2B1 state is stabilized on adding Me groups to toluene to form t-butylbenzene through reduced antibonding interactions between C1(2pπ) and Me C(2pπ) orbitals, and (d) the lowest resonance in t-butylbenzene is extensively overlapped with the second resonance and may involve strong mixing of the 2A2 and 2B1 states.
Interactions-Based Models

Abstract This paper describes a range of methods which have been proposed to study interactions in economic and social contexts. By interactions, we refer to interdependences between individual decisions which are not mediated by markets. These types of models have been employed to understand phenomena ranging from the effect of neighborhoods on the life prospects of children to the evolution of political party platforms. We provide a general choice-based framework for modelling such interactions which subsumes a number of specific models which have been studied. This framework illustrates the relationship between interactions-based models and models in statistical mechanics. Our analysis is then extended to the econometrics of these models, with an emphasis on the identification of group-level influences on individual behavior. Finally, we review some of the empirical work on interactions which has appeared in the social science literature.
Cheap Talk about Specific Investments

We consider a problem in which a buyer has private information about the efficient scale or nature of a relationship-specific investment by a producer. We show that reducing the producer's ex post bargaining power may enhance efficiency by providing incentives for the buyer to reveal his private information before the investment is made. This consideration can outweigh the well-known "hold-up" problem that arises if the producer does not have all the bargaining power.
“Stretching” the energy landscape of oxides—Effects on electrocatalysis and diffusion

Elastic strain engineering offers a new route to enable high-performance catalysts, electrochemical energy conversion devices, separation membranes and memristors. By applying mechanical stress, the inherent energy landscape of reactions involved in the material can be altered. This is the so-called mechano-chemical coupling. Here we discuss how elastic strain activates reactions on metals and oxides. We also present analogies to strained polymer reactions. A rich set of investigations have been performed on strained metal surfaces over the last 15 years, and the mechanistic reasons behind strain-induced reactivity are explained by an electronic structure model. On the other hand, the potential of strain engineering of oxides for catalytic and energy applications has been largely underexplored. In oxides, mechanical stress couples to reaction and diffusion kinetics by altering the oxygen defect formation enthalpy, migration energy barrier, adsorption energy, dissociation barrier, and charge transfer barrier. A generalization of the principles for stress activated reactions from polymers to metals to oxides is offered, and the prospect of using elastic strain to tune reaction and diffusion kinetics in functional oxides is discussed.
Irreducible Subfactors Derived from Popa’s Construction for Non-Tracial States

For an inclusion of the form \(\mathbb{C} \subseteq M_n (\mathbb{C})\), where M n (ℂ) is endowed with a state with diagonal weights λ = (λ1, …, λn), we use Popa’s construction, for non-tracial states, to obtain an irreducible inclusion of II1 factors, \(N^\lambda (Q) \subseteq M^\lambda (Q)\) of index \(\sum \tfrac{1} {{\lambda _i }}\). Mλ(Q) is identified with a subfactor inside the centralizer algebra of the canonical free product state on Q ⋆ M N (ℂ). Its structure is described by “infinite” semicircular elements as in {xc[32]}.
Arc mitigation on high voltage solar arrays

In response to the increasing demand for higher power sources in space, solar arrays are being designed with high voltages at low currents to meet this need. Unfortunately, negatively biased high voltage solar cells have been observed to arc when exposed to the low-Earth-orbit plasma environment. Analytical and numerical models of this arcing phenomenon for conventionally designed solar cells have been developed which show excellent agreement with experimental data. With an understanding of a mechanism for arcing, it is possible to assess mitigation strategies and quantify their effectiveness. It was determined that the arcing rate can be decreased by 1) increasing the interconnector work function, 2) increasing the thickness of the coverglass and cover adhesive, 3) decreasing the secondary electron yield of the coverglass and adhesive, 4) decreasing the ratio of the coverglass/adhesive dielectric constants, and 5) overhanging the coverglass. Of these, methods 4 and 5 show the most promise in mitigating or even eliminating arcing.
Improving connectionist energy minimization

Symmetric networks designed for energy minimization such as Boltzman machines and Hopfield nets are frequently investigated for use in optimization, constraint satisfaction and approximation of NP-hard problems. Nevertheless, finding a global solution (i.e., a global minimum for the energy function) is not guaranteed and even a local solution may take an exponential number of steps. We propose an improvement to the standard local activation function used for such networks. The improved algorithm guarantees that a global minimum is found in linear time for tree-like subnetworks. The algorithm, called activate, is uniform and does not assume that the network is tree-like. It can identify tree-like subnetworks even in cyclic topologies (arbitrary networks) and avoid local minima along these trees. For acyclic networks, the algorithm is guaranteed to converge to a global minimumfrom any initial state of the system (self-stabilization) and remains correct under various types of schedulers. On the negative side, we show that in the presence of cycles, no uniform algorithm exists that guarantees optimality even under a sequential asynchronous scheduler. An asynchronous scheduler can activate only one unit at a time while a synchronous scheduler can activate any number of units in a single time step. In addition, no uniform algorithm exists to optimize even acyclic networks when the scheduler is synchronous. Finally, we show how the algorithm can be improved using the cycle-cutset scheme. The general algorithm, called activate-with-cutset improves over activate and has some performance guarantees that are related to the size of the network's cycle-cutset.
Self-scaled bounds for atomic cone ranks: applications to nonnegative rank and cp-rank

The nonnegative rank of a matrix A is the smallest integer r such that A can be written as the sum of r rank-one nonnegative matrices. The nonnegative rank has received a lot of attention recently due to its application in optimization, probability and communication complexity. In this paper we study a class of atomic rank functions defined on a convex cone which generalize several notions of "positive" ranks such as nonnegative rank or cp-rank (for completely positive matrices). The main contribution of the paper is a new method to obtain lower bounds for such ranks. Additionally the bounds we propose can be computed by semidefinite programming using sum-of-squares relaxations. The idea of the lower bound relies on an atomic norm approach where the atoms are self-scaled according to the vector (or matrix, in the case of nonnegative rank) of interest. This results in a lower bound that is invariant under scaling and that enjoys other interesting structural properties. For the case of the nonnegative rank we show that our bound has an appealing connection with existing combinatorial bounds and other norm-based bounds. For example we show that our lower bound is a non-combinatorial version of the fractional rectangle cover number, while the sum-of-squares relaxation is closely related to the Lovasz $$\bar{\vartheta }$$ź¯ number of the rectangle graph of the matrix. We also prove that the lower bound is always greater than or equal to the hyperplane separation bound (and other similar "norm-based" bounds). We also discuss the case of the tensor nonnegative rank as well as the cp-rank, and compare our bound with existing results.
How Rebate Bans, Discriminatory MLS Listing Policies, and Minimum Service Requirements Can Reduce Price Competition for Real Estate Brokerage Services and Why It Matters

Institutional characteristics of a typical residential real estate transaction may create a causal link between commission rate reductions and service degradation. Such a link mitigates agents' incentive to compete on commission rates. Rebate bans, discriminatory MLS listing policies, and minimum service requirements strengthen the link thereby frustrating greater commission rate competition. Eliminating rebate bans, discriminatory MLS listing policies and minimum service requirements will increase commission rate competition and reduce wasteful rent seeking by agents.
Skill ontogeny among Tsimane forager-horticulturalists.

KEY WORDSacquisition; proficiency; expertise; development; life history theory ABSTRACT Objectives:We investigate whether age profiles of Tsimane forager-horticulturalists' reported skill development are consistent with predictions derived from life history theory about the timing of productivity and reproduction. Previous studies of forager skill devel- opment have often focused on a few abilities (e.g. hunt- ing), and neglected the broad range of skills and services typical of forager economies (e.g. childcare, craft produc- tion, music performance, story-telling). Materials and Methods:By systematically examining age patterns in reported acquisition, proficiency, and expertise across a broad range of activities including food production, childcare, and other services, we provide the most complete skill development study of a traditional subsistence society to date. Results:Our results show that: (1) most essential skills are acquired prior to first reproduction, then devel- oped further so that their productive returns meet the increasing demands of dependent offspring during adult- hood; (2) as postreproductive adults age beyond earlier years of peak performance, they report developing addi- tional conceptual and procedural proficiency, and despite greater physical frailty than younger adults, are consen- sually regarded as the most expert (especially in music and storytelling), consistent with their roles as providers and educators. We find that adults have accurate under- standings of their skillsets and skill levels -an impor- tant awareness for social exchange, comparison, learning, and pedagogy. Discussion:These findings extend our understanding of the evolved human life history by illustrating how changes in embodied capital and the needs of dependent offspring predict the development of complementary skills and services in a forager-horticulturalist economy. Am J Phys Anthropol 158:3-18, 2015. V C 2015 Wiley Period-
Susy Masses with Non-Universal Soft Breaking

The effects of non-universal scalar soft breaking masses are examined within the framework of gravity mediated supergravity GUT models with R-parity invariance. For the domain tan β≲ 25, cosmological constraints on the amount of cold dark matter predicted require that mO ≲ 200 GeV for a gluino mass of \( m\mathop g\limits^ \sim \). Thus sleptons and squarks will generally be light for \( m\mathop g\limits^ \sim \). Also, significant corrections to the gaugino mass scaling relations can occur for \( m\mathop g\limits^ \sim \). Using estimates of the accuracy expected for measurements of the cosmological parameters by the Planck sattelite, two models are examined. For the Λ CDM model, one finds that \( m\mathop g\limits^ \sim \), and that terrestial CDM detector event rates can be significantly reduced or enhanced depending on the sign of the non-universal corrections. For the vCDM model, we find \( m\mathop g\limits^ \sim \) and gaps (forbidden regions) can occur at \( m\mathop g\limits^ \sim {\text{ }} \simeq {\text{ 5}}00{\text{ }}GeV \) and \( m\mathop g\limits^ \sim {\text{ }} \simeq {\text{ 6}}00{\text{ }}GeV \) for one sign of the non-universal corrections.
Thyroxine-binding capacity of serum of mothers and newborn infants after normal pregnancies

Abstract Determinations of the thyroxine-binding capacity (TBC) of simultaneously drawn maternal and cord blood specimens at term in normal pregnancy have been carried out by means of a simplified technique. Proteinbound iodine (PBI) estimations were performed on the same specimens. Although both maternal and cord readings were consistently elevated above normal nonpregnant levels, the maternal readings were regularly greater than those of the newborn infant as regards both TBC and PBI. The explanation of the increased PBI in pregnancy as being due to increased binding capacity for thyroxine of a specific alpha globulin moiety in serum is further confirmed. Binding capacity commonly increased in greater proportion than hormone-iodine levels. The value of matched maternal and cord specimens in these studies is emphasized.
Cold Gas in Cluster Cores

I review the literature’s census of the cold gas in clusters of galaxies. Cold gas here is defined as the gas that is cooler than X-ray emitting temperatures (∼ 107K) and is not in stars. I present new Spitzer IRAC and MIPS observations of Abell 2597 that reveal significant amounts of warm dust and star formation at the level of 5 solar masses per year.
Contributions to the understanding of large-scale coherent structures in developing free turbulent shear flows

Advances in the mechanics of boundary layer flow are reported. The physical problems of large scale coherent structures in real, developing free turbulent shear flows, from the nonlinear aspects of hydrodynamic stability are addressed. The presence of fine grained turbulence in the problem, and its absence, lacks a small parameter. The problem is presented on the basis of conservation principles, which are the dynamics of the problem directed towards extracting the most physical information, however, it is emphasized that it must also involve approximations.
Metal-mask configurable RF front-end circuits

This paper describes metal-mask configurable RF circuits that offer reduced design and manufacturing risk, hence lowering nonrecurring engineering (NRE) costs. The base circuit fabric is configured for various wireless applications using only top metal and via layers. A two-stage design optimization methodology is used to optimally trade-off area and performance for design risk and cost. Measurement results are shown for a metal-mask configurable RF front-end circuit fabric that is configured for applications in 1.5 GHz GPS, 2.1 GHz WCDMA and 5 GHz WLAN using a 0.25 /spl mu/m 47 GHz f/sub T/ SiGe BiCMOS process. The final three metal and via layers are the application-specific physical design differences for the three front-end circuits. The three frontend designs consume 10.5 mA, 9.5 mA, and 8.5 mA from 2.5 V, provide noise figures of 2.5 dB, 2.8 dB and 4.5 dB, have conversion gains of 24.6 dB, 24.2 dB and 12 dB, and offer IIP3s of -8dBm, -9dBm and 4dBm, respectively.
Connective Tissue Disorders in Diabetes

Connective tissue disorders in diabetes encompass the major long-term complications, which can be attributed to alternation in the quantity and quality of structural macromolecules of the extracellular matrix. This chapter reviews the abnormalities of interstitial connective tissue involving skeleton, joints, skin, and periarticular tissues that have been considered to be associated with diabetes, including osteopenia in children and adults; hyperostosis; osteoarthritis; rheumatoid arthritis; osteolysis; scleroderma diabeticorum; Dupuytren disease; stiff hand syndrome of Lundbaek; carpal tunnel syndrome; flexor tenosynovitis; adhesive capsulitis of the shoulder and shoulder–hand syndrome; and limited joint mobility (LJM). Despite an extensive literature defining the characteristic features of the six distinct conditions resulting in limitation of hand joint mobility, recognition of the fact that these are different entities, although they may coexist, is often not appreciated. Among these conditions affecting hand joint mobility, LJM is unique in that it can occur in children and adolescents, in whom it was originally described, does not occur in the nondiabetic young population, is an important risk marker for other complications, correlates with long-term metabolic control, and has markedly decreased in frequency over the past 20 years, presumably as a result of improved control of type 1 diabetes in children. Keywords: osteopenia; hyperostosis; osteoarthritis; osteolysis; rheumatoid arthritis; scleredema diabeticorum; dupuytren disease; stiff hand syndrome; carpal tunnel syndrome; flexor tenosynovitis; limited joint mobility
Observations of infragravity waves at the Monterey ocean bottom broadband station (MOBB)

[1] Infragravity waves can be observed at the 1000 m deep ocean bottom broadband seismic station MOBB on stormy as well as quiet days. When compared to the energy of the short-period ocean waves recorded at the local buoys, infragravity waves in the longer than 20 s period band are found to be mainly locally generated from shorter-period waves. Two types of modulation of the infragravity signal are observed. First, the entire infragravity band signal is modulated in-phase with tides, possibly as a result of the nonlinear exchange of energy between the short-period waves and tidal currents. Second, a longer-period modulation of the infragravity signal is observed and is best correlated with the energy of the 14 s period ocean waves. This correlation indicates that the mechanism of generation of double frequency microseisms and infragravity waves are likely strongly related. Previously recorded data during the Oregon ULF/VLF experiment at 600 m water depth also indicate that infragravity waves are primarily locally generated.
Task partitioning via ant colony optimization for distributed assembly

We address the distributed assembly of a structure by a team of homogeneous robots. We present an ant-colony-optimization (ACO) based algorithm to partition general 2- and 3-D assembly tasks into N separate subtasks. The objective is to determine an allocation or partitioning strategy that minimizes the workload imbalance between the robots that allow for maximum assembly parallelization. This objective is achieved by extending ACO to apply to a team of ants dividing a set of tasks, with pheromone marking connections between tasks guiding decisions on task allocation. We present simulation results for various 2-D and 3-D structures and discuss the advantages of the ACO formulation in the context of other existing approaches.
Thermodynamic Curvature and Black Holes

In my talk, I will discuss black hole thermodynamics, particularly what happens when you add thermodynamic curvature to the mix. Although black hole thermodynamics is a little off the main theme of this workshop, I hope nevertheless that my message will be of some interest to researchers in supersymmetry and supergravity.
Distance-Based Decision Fusion in a Distributed Wireless Sensor Network

Target classification fusion problem in a distributed, wireless sensor network is investigated. We propose a distance-based decision fusion scheme exploiting the relationship between sensor to target distance, signal to noise ratio and classification rate, which requires less communication while achieving higher region classification rate when compared to conventional majority-vote-based fusion schemes. Several different methods are tested, and very encouraging simulation results using real world experimental data samples are also observed.
Minimally invasive randomization for collecting unbiased preferences from clickthrough logs

Clickthrough data is a particularly inexpensive and plentiful resource to obtain implicit relevance feedback for improving and personalizing search engines. However, it is well known that the probability of a user clicking on a result is strongly biased toward documents presented higher in the result set irrespective of relevance. We introduce a simple method to modify the presentation of search results that provably gives relevance judgments that are unaffected by presentation bias under reasonable assumptions. We validate this property of the training data in interactive real world experiments. Finally, we show that using these unbiased relevance judgments learning methods can be guaranteed to converge to an ideal ranking given sufficient data.
All-optical vector measurement of spin-orbit-induced torques using both polar and quadratic magneto-optic Kerr effects

We demonstrate that the magneto-optic-Kerr effect with normal light incidence can be used to obtain quantitative optical measurements of both components of spin-orbit-induced torque (both the antidamping and effective-field components) in heavy-metal/ferromagnet bilayers. This is achieved by analyzing the quadratic Kerr effect as well as the polar Kerr effect. The two effects can be distinguished by properly selecting the polarization of the incident light. We use this all-optical technique to determine the spin-orbit torques generated by a series of Pt/Permalloy samples, finding values in excellent agreement with spin-torque ferromagnetic resonance measurements.
Aspects of D instantons

D-instantons are responsible for several important nonperturbative effects in superstring theory.
Fox reimbedding and Bing submanifolds

Let M be an orientable closed connected 3-manifold. We introduce the notion of amalgamated Heegaard genus of M with respect to a closed separating 2-manifold F, and use it to show that the following two statements are equivalent: (i) a compact connected 3-manifold Y can be embedded in M so that the exterior of the image of Y is a union of handlebodies; and (ii) a compact connected 3-manifold Y can be embedded in M so that every knot in M can be isotoped to lie within the image of Y . Our result can be regarded as a common generalization of the reimbedding theorem by Fox [Fox48] and the characterization of 3-sphere by Bing [Bin58], as well as more recent results of Hass and Thompson [HT89] and Kobayashi and Nishi [KN94].
Voting with their feet ? access to infrastructure and migration in Nepal

Using bilateral migration flow data from the 2010 population census of Nepal, this paper provides evidence on the importance of public infrastructure and services in determining migration flows. The empirical specification, based on a generalized nested logit model, corrects for the non-random selection of migrants. The results show that migrants prefer areas that are nearer to paved roads and have better access to electricity. Apart from electricity's impact on income and through income on migration, the econometric results indicate that migrants attach substantial amenity value to access to electricity. These findings have important implications for the placement of basic infrastructure projects and the way benefits from these projects are evaluated.
Geometric spectral theory for compact operators

For an n-tuple A = (A1,··· ,An) of compact operators we define the joint point spectrum of A to be the set �p(A) = {(z1,··· ,zn) ∈ C n : ker(I + z1A1 + ··· + znAn) 6 (0)}. We prove in several situations that the operators in A pairwise commute if and only ifp(A) consists of countably many, locally finite, hyper- planes in C n . In particular, we show that if A is an n-tuple of N × N normal matrices, then these matrices pairwise commute if and only if the polynomial
Choices under Risk in Rural Peru

This paper estimates the risk preferences of cotton farmers in Southern Peru, using the results from a multiple-price-list lottery game. Assuming that preferences conform to two of the leading models of decision under risk|Expected Utility Theory (EUT) and Cumulative Prospect Theory (CPT)|wend strong evidence of moderate risk aversion. Once we include individual characteristics in the estimation of risk parameters, we observe that farmers use subjective nonlinear probability weighting, a behavior consistent with CPT. Interestingly, when we allow for preference heterogeneity via the estimation of mixture models|where the proportion of subjects who behave according to EUT or to CPT is endogenously determined|wend that the majority of farmers' choices are best explained by CPT. We further hypothesize that the multiple switching behavior observed in our sample can be explained by nonlinear probability weighting made in a context of large random calculation mistakes; the evidence found on this regard is mixed. Finally, wend that attaining higher education is the single most important individual characteristic correlated with risk preferences, a result that suggests a connection between cognitive abilities and behavior towards risk.
Scaling molecular dynamics to 3000 processors with projections: a performance analysis case study

Some of the most challenging applications to parallelize scalably are the ones that present a relatively small amount of computation per iteration. Multiple interacting performance challenges must be identified and solved to attain high parallel efficiency in such cases. We present a case study involving NAMD, a parallel molecular dynamics application, and efforts to scale it to run on 3000 processors with Tera-FLOPS level performance. NAMD is implemented in Charm++, and the performance analysis was carried out using "projections", the performance visualization/analysis tool associated with Charm++. We will showcase a series of optimizations facilitated by projections. The resultant performance of NAMD led to a Gordon Bell award at SC2002.
Q-Curvature on a Class of Manifolds with Dimension at Least 5

For a smooth compact Riemannian manifold with positive Yamabe invariant, positive Q-curvature, and dimension at least 5, we prove the existence of a conformal metric with constant Q-curvature. Our approach is based on the study of an extremal problem for a new functional involving the Paneitz operator.© 2015 Wiley Periodicals, Inc.
Industry Support of Medical Research: Important Opportunity or Treacherous Pitfall?

Pharmaceutical and device manufacturers fund more than half of the medical research in the U.S. Research funding by for-profit companies has increased over the past 20 years, while federal funding has declined. Research funding from for-profit medical companies is seen as tainted by many academicians because of potential biases and prior misbehavior by both investigators and companies. Yet NIH is encouraging partnerships between the public and private sectors to enhance scientific discovery. There are instances, such as methods for improving drug adherence and post-marketing drug surveillance, where the interests of academician researchers and industry could be aligned. We provide examples of ethically performed industry-funded research and a set of principles and benchmarks for ethically credible academic-industry partnerships that could allow academic researchers, for-profit companies, and the public to benefit.
Green growth, technology and innovation

The paper explores existing patterns of green innovation and presents an overview of green innovation policies for developing countries. The key findings from the empirical analysis are: (1) frontier green innovations are concentrated in high-income countries, few in developing countries but growing; (2) the most technologically-sophisticated developing countries are emerging as significant innovators but limited to a few technology fields; (3) there is very little South-South collaboration; (4) there is potential for expanding green production and trade; and (5) there has been little base-of-pyramid green innovation to meet the needs of poor consumers, and it is too early to draw conclusions about its scalability. To promote green innovation, technology and environmental policies work best in tandem, focusing on three complementary areas: (1) to promote frontier innovation, it is advisable to limit local technology-push support to countries with sufficient technological capabilities -- but there is also a need to provide global technology-push support for base-of-pyramid and neglected technologies including through a pool of long-term, stable funds supported by demand-pull mechanisms such as prizes; (2) to promote catch-up innovation, it is essential both to facilitate technology access and to stimulate technology absorption by firms -- with critical roles played by international trade and foreign direct investment, with firm demand spurred by public procurement, regulations and standards; and (3) to develop absorptive capacity, there is a need to strengthen skills and to improve the prevailing business environment for innovation -- to foster increased experimentation, global learning, and talent attraction and retention. There is still considerable progress to be made in ranking green innovation policies as most appropriate for different developing country contexts -- based on more impact evaluation studies of innovation policies targeted at green technologies.
Sea breeze forcing of estuary turbulence and air-water CO2 exchange

[1] The sea breeze is often a dominant meteorological feature at the coastline, but little is known about its estuarine impacts. Measurements at an anchored catamaran and meteorological stations along the Hudson River and New York Bay estuarine system are used to illustrate some basic characteristics and impacts of the feature. The sea breeze propagates inland, arriving in phase with peak solar forcing at seaward stations, but several hours later at up-estuary stations. Passage of the sea breeze front raises the water-to-air CO2 flux by 1–2 orders of magnitude, and drives turbulence comparable to spring tide levels in the upper meter of the water column, where most primary productivity occurs in this highly turbid system. Modeling and observational studies often use remotely-measured winds to compute air-water fluxes (e.g., momentum, CO2), and this leads to a factor of two flux error on sea breeze days during the study.
The ERIM TOPR In Optical Data Processing

The ERIM Thermoplastic Optical Phase Recorder (TOPR) is a real-time, two-dimensional light modulator. The modulator employs electron beam writing on a deformable and reusable thermoplastic film. The varying thickness film causes phase modulation of a light beam in an optical processor. The data written into the plastic can be stored for periods from less than 0.5 sec to many months depending on the temperature at which the plastic is maintained. The time bandwidth product of the device is greater than 106 and its optical quality is suitable for optical data processing. Because of these features the TOPR, combined with an optical data processor, can offer advantages in size, cost, complexity, and processing speed relative to digital computers. Alternatively, the TOPR can be used in a hybrid optical-digital computer to provide preprocessing of data or a "quick-look" capability for digital data processing decisions. This paper describes characteristics of the TOPR and an application of the TOPR to processing of imagery from data recorded in a unique polar format. Introduction The purpose of this paper is to describe a real-time spatial light modulator and its use in a coherent optical computer in a practical application; synthetic aperture radar (SAR) data processing. In this modulator a scanning, intensity-modulated electron beam is used to deform a thin thermoplastic film. A large area light beam is passed through the film (or reflected from it) and the deformation image is impressed onto the light beam as a two-dimensionql phase modulation. This modulator was developed specifically for optical data processing', thus, it has good optical quality, large space-bandwidth product, near real-time response, and a reusable modulation medium. In the following we will discuss the modulator design, its specifications, and its performance in the SAR data processing application.© (1977) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Spectral weight in holographic scaling geometries

We compute the low energy spectral density of transverse currents in theories with holographic duals that exhibit an emergent scaling symmetry characterized by dynamical critical exponent z and hyperscaling violation exponent θ. For any finite z and θ, the low energy spectral density is exponentially small at nonzero momentum. This indicates that any nonzero momentum low energy excitations of putative hidden Fermi surfaces are not visible in the classical bulk limit. We furthermore show that if the limit z → ∞ is taken with the ratio η = −θ/z > 0 held fixed, then the resulting theory is locally quantum critical with an entropy density that vanishes at low temperatures as s ~ T η . In these cases the low energy spectral weight at nonzero momentum is not exponentially suppressed, possibly indicating a more fermionic nature of these theories.
Engineering Living Functional Materials

Natural materials, such as bone, integrate living cells composed of organic molecules together with inorganic components. This enables combinations of functionalities, such as mechanical strength and the ability to regenerate and remodel, which are not present in existing synthetic materials. Taking a cue from nature, we propose that engineered ‘living functional materials’ and ‘living materials synthesis platforms’ that incorporate both living systems and inorganic components could transform the performance and the manufacturing of materials. As a proof-of-concept, we recently demonstrated that synthetic gene circuits in Escherichia coli enabled biofilms to be both a functional material in its own right and a materials-synthesis platform. To demonstrate the former, we engineered E. coli biofilms into a chemical-inducer-responsive electrical switch. To demonstrate the latter, we engineered E. coli biofilms to dynamically organize biotic-abiotic materials across multiple length scales, template gold nanoro...
The minimum expectation selection problem

We define the min-min expectation selection problem (resp. max-min expectation selection problem) to be that of selecting k out of n given discrete probability distributions, to minimize (resp. maximize) the expectation of the minimum value resulting when independent random variables are drawn from the selected distributions. We assume each distribution has finitely many atoms. Let d be the number of distinct values in the support of the distributions. We show that if d is a constant greater than 2, the min-min expectation problem is NP-complete but admits a fully polynomial time approximation scheme. For d an arbitrary integer, it is NP-hard to approximate the min-min expectation problem within any constant approximation factor. The max-min expectation problem is polynomially solvable for constant d; we leave open its complexity for variable d. We also show similar results for binary selection problems in which we must choose one distribution from each of n pairs of distributions.
Structural disorder and magnetism of the semiconducting clathrate Eu8Ga16Ge30

Abstract The temperature dependence of the atomic displacement parameters for an isotopically enriched Eu8Ga16Ge30 crystal determined from refinements of neutron diffraction data show the anomalously large values for the Eu atom in the large cage persist from 295 to 12 K. The Eu site in the large cage is modeled by splitting it into four fractionally occupied positions, displaced 0.4 A from the cage center. Fourier maps of this Eu site support this view in showing residual nuclear density with distinct peaks in the directions of the split-atom positions, and lesser density at the cage center position. The Ga and Ge atoms appear to be fully disordered on the three distinct framework sites. In comparing the isostructural X8Ga16Ge30 (X=Eu, Sr, Ba) compounds, the positional disorder around the large cage site increases progressively with decreasing size of the caged atom. Below 35 K, Eu8Ga16Ge30 orders ferromagnetically, with the preferred direction of the Eu moments along (100). The projected saturation value of the Eu moment, 7 μB, equals the free ion value.
Synthesis of 6,16,22,32-tetrahydroxy[3.3.3.3]metacyclophane with the aid of a new copper catalyst

Abstract Metacyclophane 2 has been prepared in 4 steps starting from 2-bromoanisole with the aid of a new copper catalyst. The catalyst was prepared by mixing CuBr-SMe 2 with LiSPh and LiBr in THF.
Role of Si2N2O in the Passive Oxidation of Chemically-Vapor-Deposited Si3N4

The results of two-step oxidation experiments on chemically-vapor-deposited Si3N4 and SiC at 1350 C show that a correlation exists between the presence of a Si2N2O interphase and the strong oxidation resistance of Si3N4. During normal oxidation, k sub p for SiC was 15 times higher than that for Si3N4, and the oxide scale on Si3N4 was found by SEM and TEM to contain a prominent Si2N2O inner layer. However, when oxidized samples are annealed in Ar for 1.5 h at 1500 C and reoxidized at 1350 C as before, three things happen: the oxidation k sub p increases over 55-fold for Si3N4, and 3.5-fold for SiC; the Si3N4 and SiC oxidize with nearly equal k sub p's; and, most significantly, the oxide scale on Si3N4 is found to be lacking an inner Si2N2O layer. The implications of this correlation for the competing models of Si3N4 oxidation are discussed.
Silicon and Nickel Enrichment in Planet Host Stars: Observations and Implications for the Core Accretion Theory of Planet Formation

We present evidence that stars with planets exhibit statistically significant silicon and nickel enrichment over the general metal-rich population. We also present simulations that predict silicon enhancement of planet hosts within the context of the core accretion hypothesis for giant planet formation. Because silicon and oxygen are both α-elements, [Si/Fe] traces [O/Fe], so the silicon enhancement in planet hosts predicts that these stars are oxygen-rich as well. We present new numerical simulations of planet formation by core accretion that establish the timescale on which a Jovian planet reaches rapid gas accretion, trga, as a function of solid surface density σsolid: (trga/1 Myr) = (σsolid/25.0 g cm-2)-1.44. This relation enables us to construct Monte Carlo simulations that predict the fraction of star-disk systems that form planets as a function of [Fe/H], [Si/Fe], disk mass, outer disk radius, and disk lifetime. Our simulations reproduce both the known planet-metallicity correlation and the planet-silicon correlation reported in this paper. The simulations predict that 15% of solar-type stars form Jupiter-mass planets, in agreement with 12% predicted from extrapolation of the observed planet frequency-semimajor axis distribution. Although a simple interpretation of core accretion predicts that the planet-silicon correlation should be much stronger than the planet-nickel correlation, we observe the same degree of silicon and nickel enhancement in planet hosts. If this result persists once more planets have been discovered, it might indicate a complexity in the chemistry of planet formation beyond the simple accumulation of solids in the core accretion theory.
Effect of lacunocanalicular architecture on hydraulic conductance in bone tissue: Implications for bone health and evolution

Bone tissue health depends largely on efficient fluid and solute transport between the blood supply and cells that are the living component of the tissue. We hypothesized that the lacunocanalicular hydraulic network, which is defined by the pericellular fluid space that is common to all bone tissue, is optimized to transport fluid and solutes between the blood supply and bone cells. An analytical study was carried out to evaluate the effect of osteonal architecture, including the osteon diameter, number of annular lamellar regions, and number and length of canalicular channels, on fluid transport between the blood supply and bone cells. On the basis of this analysis, we conclude that osteon size is limited to the distance over which fluid and solutes can be transported efficiently between the blood supply and cells. This analytic model suggests that hydraulic conductivity is highest in lamellar regions closest to the Haversian canal (HC) and decreases with increasing distance from the blood supply, reaching a plateau after the fifth lamella (169 micro m radius). Furthermore, an increase in the diameter of the HC, or a decrease in the length of canaliculi, reduces the hydraulic conductivity within the lacunocanalicular network. Applying the principle of minimal expenditure of energy to this analysis, the path distance comprising five or six lamellar regions represents an effective limit for fluid and solute transport between the blood supply and cells; beyond this threshold, hydraulic resistance in the network increases and additional energy expenditure is necessary for further transportation. This suggests that transport is optimized to meet metabolic demands concomitant with a minimal expenditure of energy. This fundamental new insight into bone structure and physiology may provide a new basis of understanding for tissue engineering, bone physiology in health and disease, and evolutionary biology.
Recording for the blind and dyslexic: the development of an Internet accessible online catalog

Recording for the Blind and Dyslexic (formerly Recording for the Blind) has been providing audio recordings of educational texts since its founding in 1948. RFB&D's master tape library currently contains over 80,000 volumes, making it the largest resource of its kind in the world. Beginning in 1992, RFB&D initiated a project to develop an online public access catalog that would allow both institutional providers and individual borrowers to search its holdings and order recorded texts via the Internet. Also in 1993, a coordinated pilot project was begun to allow a limited test group of institutional sites and individuals the ability to use the catalog‐ordering mechanism in an effort to gather structured feedback on the usefulness of the system and suggestions for improvements. Although the project cannot be considered an overwhelming success, much insight has been gained as a result of our efforts and will be of considerable value in the development of a future improved version of RFB&D's online public access catalog.
Balanced excitation and inhibition in temperature responses to meth

Fatal hyperthermia after administration of various amphetamines is well-known clinical phenomenon, however, there is no consistent theory explaining its etiology and/or pathogenesis. Dose-dependence of temperature responses to methamphetamine is intricate. Recently, using mathematical modeling it was suggested that delicate interplay of excitatory and inhibitory mechanisms underlies this complexity.
Embeddings of Discrete Groups and the Speed of Random Walks

Let G be a group generated by a finite set S and equipped with the associated left-invariant word metric d G . For a Banach space X, let α * X (G) (respectively, α / # X (G)) be the supremum over all α ≥ 0 such that there exists a Lipschitz mapping (respectively, an equivariant mapping) f:G → X and c > 0 such that for all x, y ∈ G we have ‖ f(x) − f(y)‖ ≥ c · d G (x, y) α . In particular, the Hilbert compression exponent (respectively, the equivariant Hilbert compression exponent) of G is (respectively, ). We show that if X has modulus of smoothness of power type p, then . Here β * (G) is the largest β ≥ 0 for which there exists a set of generators S of G and c > 0, such that for all we have , where { W t } ∞ t=0 is the canonical simple random walk on the Cayley graph of G determined by S, starting at the identity element. This result is sharp when X = L p , generalizes a theorem of Guentner and Kaminker (20), and answers a question posed by Tessera (37). We also show that, if then . This improves the previous bound due to Stalder and Valette (36). We deduce that if we write and then and use this result to answer a question posed by Tessera in (37) on the relation between the Hilbert compression exponent and the isoperimetric profile of the balls in G. We also show that the cyclic lamplighter groups C 2 ≀ C n embed into L 1 with uniformly bounded distortion, answering a question posed by Lee, Naor, and Peres in (26). Finally, we use these results to show that edge Markov type need not imply Enflo type.
Aerosound from corner flow and flap flow

Noise generation at the edge of a wing flap is analyzed. The phenomenon as a single vortex moving around a corner in an incompressible, potential flow is modelled. Vortex image retarding effects are proposed as an explanation for small Strouhal numbers. The model surface pressures, sound pressures (using Curle's theory), and Mach number dependencies agree with wind tunnel experiments. A double pressure peak is found in the model (credited to image action) which is qualitatively similar to measured sound correlations. Incompressible flow aerosound calculations are discussed. The effects of a series of vortices moving in the same idealized potential flow are also studied. The vortices are assumed to be statistically independent so their intensities can be added. The frequency of appearance of the vortices are determined from measurements. Diffraction effects caused by the presence of the wing near the dipole sound radiators on the flap surfaces are included.
DNA segmentation as a model selection process

Previous divide-and-conquer segmentation analyses of DNA sequences do not provide a satisfactory stopping criterion for the recursion. This paper proposes that segmentation be considered as a model selection process. Using the tools in model selection, a limit for the stopping criterion on the relaxed end can be determined. The Bayesian information criterion, in particular, provides a much more stringent stopping criterion than what is currently used. Such a stringent criterion can be used to delineate larger DNA domains. A relationship between the stopping criterion and the average domain size is empirically determined, which may aid in the determination of isochore borders.